摘要:

14 Biological Chemistry Part (iii) Nucleic Acids By R. J. H. DAVIES Biochemistry Department Medical Biology Centre The Queen’s University of Belfast Belfast BT9 7BL 1 Introduction Two major goals in nucleic acid chemistry have been attained this year. It was announced appropriately enough at the Centennial Meeting of the American Chemical Society that Khorana’s group has successfully synthesized the complete gene for the tyrosine suppressor tRNA of E. coli. This comprises not only the structural part of the gene which is transcribed to give the tRNA precursor molecule of 126 nucleotides but also the control elements a promoter region of 56 nuc-leotides and a non-transcribed terminator region of 25 nucleotides. In all the DNA duplex consists of 207 base pairs (molecular weight ca.140000) and is the culmina- tion of 9 years’ work undertaken by 24 postdoctoral fellows. The synthetic gene has been successfully introduced into an amber mutant of E. coli and shown to be biologically functional. The determination of the complete sequence of bacteriophage MS2 RNA (a total of 3569 nucleotides) by Fiers and his co-workersl is another brilliant achievement based on years of patient and skilful endeavour. This work will no doubt be matched in the very near future by the complete sequencing of bacteriophage 4x174 DNA in Sanger’s laboratory. As little as 5 years ago this situation would have appeared unthinkable because at that time the sequencing of even small tracts of DNA posed seemingly insuperable technical problems.The position has been transformed since then by the possibilities of using restriction endonucleases to produce defined fragments of DNA and the development of a number of elegant and rapid methods for sequencing them. In many instances DNA sequencing is now a simpler exercise than RNA sequencing. Indeed the sequencing of both types of nucleic acid should shortly become routine laboratory procedures. This facility will open the door to major advances in our understanding of how proteins and other molecules interact with DNA and RNA in functional and structural capacities. The debate concerning the construction and exploitation of recombinant DNA molecules whereby in principle the genes from any living organisms or virus can be linked to the genes of any other species is far from over.Nevertheless despite the misgivings of several eminent geneticists a consensus is emerging in Europe and America that this kind of research should be permitted to go ahead with appropriate 1 W. Fiers R. Contreras F. Duerinck G. Haegeman D. Iserentant J. Merregaert W. Min Jou F. Molemans,A. Raeymakers,A. Van den Berghe G. Volckaert and M. Ysebaert Nature 1976,260,500. 375 376 R.J. H.Davies experimental safeguards. In Britain official recommendations have now been published2 which divide experiments into four categories according to their hazards and stipulate a related code of practice. It is recommended that research workers undertaking experiments involving recombinant DNA must notify the Health and Safety Commission and an independent Genetic Manipulation Advisory Group.The latter body will categorize the work and advise on the level of containment required. Besides recombinant DNA research another growth area at present is the investigation of chromosome structure which has expanded rapidly since the discovery of the subunit structure of chromatin. Some recent advances in both these fields are summarized at the end of this Report. 2 Bases and Nucleosides When 5-chloromercuriuridine is treated with Li2FdC14 in methanol3 an organopal- ladium intermediate is generated in situ which will react with olefins under mild conditions to give substituted 5-vinyluridines (1). These may be subsequently 0 I ribosyl (1) hydrogenated to the corresponding 5-alkyluridines.This simple preparative proce- dure has the advantages that no protection of the nucleoside is necessary and that the olefin may be substituted by a number of functional groups such as carboxymethyl which are unreactive towards organopalladium compounds. 5-Ethynyluracil(2) has been prepared from both 5-formyluraci14 and 5-acetyl~racil;~ 5-formyluracil has also been converted4 into the 2’-deoxyribonucleoside (3). A new general procedure R (2) R=H (3) R = 2’-deoxyribosyl for the synthesis of C-5 pyrimidine nucleosides6 is based on the methoxyacrylate derivative(4) as a key intermediate. Condensation of (4) with guanidine followed by removal of protecting groups yields pseudoisocytidine (5); reaction with urea or * ‘Report of the Working Party on the Practice of Genetic Manipulation’ Cmnd.6600 HMSO. 3 D. E. Bergstrom and J. L. Ruth J. Amer. Chem. Sac. 1976,98 1587. J. Perman R. A. Sharma and M. Bobek Tetrahedron Letters 1976 2427. P. J. Barr A. S. Jones and R. T. Walker Nucleic Acids Res. 1976 3 2845. C. K. Chu I. Wempen K. A. Watanabe and J. J. Fox J. Org. Chem. 1976,41 2793. Biological Chemistry -Part (iii)Nucleic Acids (4 ) (5 ) thiourea followed by deblocking gives pseudouridine and 2-thiopseudouridine respectively. The Eschenmoser sulphide contraction provides a useful route to C-substituted nucleosides via the readily accessible S-phenacyl derivatives of 6-thiopurine and of 2- or 4-thiopyrimidine nucleosides.' For example the protected 6-phenacylthiopurine nucleoside (6) gives the 6-phenacylpurine nucleoside (7) in high yield on treatment with potassium t-butoxide and triphenylphosphine in xylene.OAc OAc (6) R = SCHZCOPh (7) R = CHZCOPh Methylation at the C-5 positions of dimethyluracil photodimers (8) has been achieved using a mixture of methyl iodide and silver oxide in dimethylformamide.' Monomethylation gives rise to the corresponding mixed dimer of dimethyluracil and dimethylthymine (9). The four possible isomers of the mixed dimer have all been (8) R'=R2=H (9) R' = H,R2= Me isolated and this has allowed confirmation of the stereochemistry of the thymine- uracil heterodimer formed in u.v.-irradiated DNA. The possibility of photocycload-dition between the 5,6-double bond of uracil and the 7,s-double bond of adenine has H.Vorbriiggen and K. Krolikiewicz Angew. Chem. Internat. Edn. 1976,15,689. 8 H. Taguchi and S. Y.Wang Biochem. Biophys. Res. Comm. 1976,13,356. 378 R. J. H.Davies been demonstrated.' When uracil and adenine are linked through their respective N-1 and N-9 positions with a trimethylene bridge irradiation at 254 nm generates the azacyclobutane derivative (10). Improved syntheses of 5-hydroperoxy-methyluracil which is produced on y-irradiation of thymine in aqueous solution have been reported." Two of the principal products formed on y-radiolysis of deoxyadenosine have been identified" as 7,8-dihydro-8-oxo-deoxyadenosine(11) and the cyclonucleoside (12). An excellent comprehensive survey1* of the photo- chemistry of nucleic acids which includes chapters on their radiation chemistry has recently been published.0 OH (10) (11) (12) The previously unknown 02-methylcytidine (13) and 02-ethylcytidine (14) are formed as major products when the potent carcinogens N-methyl-N-nitrosourea and I ribosyl (13) R=Me (14) R = Et N-ethyl-N-nitrosourea react with cytidine in neutral aqueous s01ution.l~ Diethyl sulphate and ethyl methanesulphonate also react at this site but dimethyl sulphate which is not appreciably carcinogenic alkylates almost exclusively at N-3. Although the products are not in doubt the mechanism of the reaction of cytosine with hydroxylamine is still controversial. On the basis of kinetic and stereochemical investigations Schalke and HaIll4 have concluded that direct addition of hydroxyl-amine across the 5,6-double bond of cytosine to give the undetectable inter- mediate (13 is most unlikely.However the deuterium exchange data of Blackburn ef a1." suggest that reversible formation of (15)does occur and that the addition of 9 S. Paszyc B. Skalski and G. Wenska Tetrahearon Letters 1976 449. 10 B.-S. Hahn and S. Y. Wang I. Org. Chem. 1976,41,567. 11 N. Mariaggi and R. Teoule Bull. SOC.chim.France 1976 1595; N. Mariaggi J. Cadet and R. Teoule Tetrahedron 1976,32,2385. 12 'Photochemistry and Photobiology of Nucleic Acids' ed. S. Y. Wang Academic Press London 1976 Vols.1 and 2. 13 B. Singer F.E.B.S. Letters 1976,63,85. 14 P.M. Schalke and C. D. Hall J.C.S. Chem. Comm. 1976,391. IS G. M. Blackburn V. C. Solan D. M. Brown and P. F. Coe J.C.S. Chem. Comm. 1976,724. 379 Biological Chemistry -Part (iii)Nucleic Acids 0@.2HH NHL (15) hydroxylamine is only partially stereospecific. A very detailed examination l6 of the tautomerism of cytosine and 3-methylcytosine in aqueous solution has been carried out by means of temperature-jump relaxation measurements. The reduction of N-substituted adenines" and of 7,9-disubstituted purines'' by sodium borohydride has been investigated. Benzoylation of the exocyclic amino- group facilitates reaction with the adenine derivatives and stable dihydroadenines may be isolated. N6-Benzoyl-3-benzyladenineis reduced to the 1,2-dihydro- derivative and N6-benzoyl-9-benzyladeninegives the 7,8-dihydro-compound.7,9- Disubstituted purines are readily reduced to the corresponding 7,8-dihydro species which can act as selective reducing agents for imines and immonium salts. Dis- cadenine a potent spore germination inhibitor from the cellular slime mould has been identifiedlg as 3-(3-amino-3-carboxypropyl)-6-(3-methyl-2-buteny1amino)purine (16). Crystal structure analysis2' of 3-methylguanine proves that it exists as the N(7)-H tautomer (17) rather than as the mesoionic N( 1)-H tautomer (18). The crystal structure of monosodium urate monohydrate NHCH,CH=CMe I I I CH2CH2CHCOOH Me Me I NH2 the deposition of which is responsible for gout has also been determined.** The crystal faces which interact with the lysosomal membrane during an attack of gout contain stacks of edge-on urate anions separated by stacks of sodium ions and water molecules.The 'laterally elongated' bases lin -benzoguanine (19) and lin -benzoadenine (20) have been synthesized,22 together with a number of derivatives of lin -benzoadenine including the ribonucleoside (21). Some of these compounds are strongly fluores- cent which should be useful for monitoring their interaction with various enzymes l6 M. Dreyfus 0.Bensaude G. Dodin and J. E. Dubois 1. Amer. Chem. Soc. 1976,98,6338. l7 Y. Maki M. Suzuki and K. Ozeki Tetrahedron Letters 1976 1199. 18 S. M. Hecht B. L. Adams and J. W. Kozarich J. Org. Chem. 1976,41 2303. 19 H. Abe M. Uchiyama Y. Tanaka and H.Saito Tetrahedron Letters 1976 3807. 2O J. E. Abola D. J. Abraham and L. B. Townsend Tetrahedron Letters 1976,3483. *l N. S. Mandel and G. S. Mandel J. Amer. Chem. Soc. 1976,98 2319. 22 G.E. Keyser and N. J. Leonard J. Org. Chem. 1976,41,3529;N. J. Leonard M. A. Specker. and A. G. Morrice J. Amer. Chem. Soc. 1976,98 3987. 380 R.J. H.Davies (19) R’ = OH R2= NH2 R3 = H (20) R’ =NH2 R2 =R3 =H (21) R’ = NH2 R2= H R3= ribosyl involved in nucleic acid metabolism. A number of fluorescent analogues of the Y base from tRNA with the general structure (22) have been prepared by treating guanine with substituted mal~nodialdehydes.~~ The guanosine analogue 2-azidoinosine and its 5’-phosphate and triphosphate are also fluorescent and may serve as photoaffinity labels.24 However the use of azidonucleotides as photoaffinity reagents for enzymes should be tempered by the ob~ervation~~ that thiol compounds the presence of which is often necessary to maintain full enzyme activity in solution readily reduce 8-azidoadenosine and its nucleotides to the corresponding 8-aminoadenosine derivative.The reaction is particularly rapid with dithiols but very much slower with monothiols such as mercaptoethanol. The ‘naked’ anions produced when cyanide or fluoride ions complex with the crown ether [18lcrown-6 are powerful nucleophiles. 5’-Cyano-nucleosides may be prepared from 2’,3’- 0-isopropylidene-5’- 0-tosylnucleosides by treatment with [18lcrown-6 and alkali cyanides in dry acetonitrile.26 Similarly 2’,3’,5’-tri-O- acetyl-8-fluoroadenosinehas been synthesized2’ from the 8-bromo-compound using potassium fluoride and the crown ether.Benzoyltetrazole has been advocated2* as a mild benzoylating reagent for nucleosides. Full details have now appeared29 of the synthesis of the antibiotic nucleocidin (23) which contains a 4’-fluoro substituent. The conversion of tubercidin into the elusive 2’-deoxytubercidin (24) has also been a~hieved.~’ The proceedings of a recent conference3’ contain contributions on many aspects of nucleoside and nucleotide chemistry by Japanese research workers. 23 R. C. Moschel and N. J. Leonard J. Org. Chem. 1976,41 294. 24 G. Wiegand and R. Kaleja European J. Biochem. 1976,65,473. *S I. L. Cartwright D. W.Hutchinson and V. W. Armstrong Nucleic Acids Res. 1976 3 2331. 26 W. Meyer E. Bohnke and H. Follmann Angew. Chem. Internat. Edn. 1976,15 499. 27 Y. Kobayashi I. Kumadaki A. Ohsawa and S. Murakami J.C.S. Chem. Comm. 1976,430. 28 J. Stawinski T. Hozumi and S. A. Narang J.C.S. Chem. Comm. 1976 243. 29 I. D. Jenkins J. P. H. Verheyden and J. G. Moffatt J. Amer. Chem. SOC. 1976,98 3346. 30 M. J. Robins and W. H. Muhs J.C.S. Chem. Cornm. 1976,269. 31 ‘Proceedings of the Fourth Symposium onNucleic Acid Chemistry’ compiled by E. Coast Nucleic Acids Res. 1976 Special Publication No. 2. Biological Chemistry -Part (iii)Nucleic Acids 381 OH OH OH (24) 3 Nucleotides The commonly used phosphate protecting groups cyanoethyl trichloroethyl and phenyl can all be removed from nucleotide triesters without affecting the internuc- leotide linkage by the action of tetrabutylammonium fluoride for 30 min at room temperatu~e.~~ The ATP analogues adenosine 5’40-1-thiotriphosphate) and adenosine 5’-(0-2-thiotriphosphate)exist as diastereomers.The two individual diastereomers of each of these compounds have been ~ynthesized~~ by enzymatic methods. A new procedure for synthesis of the pyrophosphate bond34 involves the use of a potent phosphorylating agent which is generated in a mixture of cyanoethyl phosphate dicyclohexylcarbodi-imide,and mesitylenesulphonyl chloride. It has been used to prepare the tetraphosphates ppdGpp and ppGpp from the nucleoside 3‘,5’-diphosphates. The so-called ‘hot spot’ compound G5’pppp5’G previously found in the brine shrimp has now been identified35 in fungi together with its 3‘-phosphate G5’pppp5’Gp and another partially characterized guanosine polyphosphate.These compounds appear to act as regulators of fungal RNA polymerase enzymes and may therefore be important in cellular differentiation. A regulatory role has also been attributed36 to A5’pppp5‘A the concentration of which in mammalian cells varies with their proliferative activity. The ‘rigid nucleotide’ concept which was advanced by Sundaralingam mainly on the basis of the solid-state structures of mononucleotides has been ~hallenged.~’ High-resolution ‘H n.m.r. data show that in aqueous solution the backbone confor- mation of adenosine is as flexible as that of 3‘-AMP 5’-AMP or 5‘-ADP.Furthermore the flexible conformation of the monomeric components is conserved in oligonucleotides and poly(A) under conditions where the bases are not stacked. These findings contradict the contention that upon addition of a phosphate group the flexible conformation of a nucleoside becomes essentially rigid and that the rigid mononucleotide conformation is maintained in oligo- and poly-nucleotides. Rigid sugar conformations are exhibited by cyclonucleosides and cyclic nucleotides and an n.m.r. study of 18of these compounds has been made.38 The 31P n.m.r. spectrum of 32 K. K. Ogilvie S. L. Beaucage and D. W. Entwistle TetrahedronLerrers 1976 1255. 33 F. Eckstein and R. S. Goody Biochemistry 1976 15 1685. 34 G. N. Bennett G. R.Gough and P. T. Gilham Biochemistry 1976 IS,4623. 35 H. B. LiJohn L. E. Cameron D. R. McNaughton and G. R. Klassen Biuchem. Biophys. Res. Comm. 1976,66 460. 36 E. Rapaport and P. C. Zamecnik Proc. Nar. Acad. Sci. U.S.A. 1976 73 3984. 37 F. E. Evans and R. H. Sarma Name 1976,263 567. 38 C.-H. Lee and R. H. Sarma J. Amer. Chem. Soc. 1976,98 3541. 382 R.J. H.Davies ATP indicates3’ that in non-aqueous media the molecule is folded so that the triphosphate side-chain lies across the adenine ring with hydrogen-bonding between the P-phosphate and 6-amino-groups; a similar conformation is proposed for all the other common nucleoside di- and tri-phosphates in anhydrous media. Dinucleoside Monophosphates.-Reflecting the great progress of recent years physical and structural studies of nucleic acid components have now reached a point where the emphasis is shifting from the mononucleotide to the dinucleoside monophosphate level.The dinucleoside monophosphates are the smallest compo- nents which incorporate all the structural features needed to describe the conforma- tion of larger polynucleotides. Full descriptions of the crystal structures of the sodium salts of ApU and GpC are now a~ailable.~’ In both cases the dinucleoside monophosphates form a small segment of right-handed antiparallel double-helical RNA in the crystal by Watson-Crick base-pairing. The structure of the calcium salt of GpC has also been determined.41 The triethylammonium salt of the self- complementary dinucleoside monophosphate TpdA has an unusual structure4* incorporating Hoogsteen base-pairing between adenine and thymine.Although the nucleoside units within individual TpdA molecules are related as in a right-handed helix neighbouring TpdA molecules in the crystal form a left-handed helix. A possible model for the structure of poly(T) has been derived from the crystal of the dinucleotide pTpT. By means of n.m.r. spectroscopy base-pairing has been detected,44 in aqueous solution at low temperatures with the self-complementary species GpC and CpG and with the complementary mixture of GpU and ApC. A very thorough study has been made45 of the ’H n.m.r. spectra of all the dipurine and dipyrimidine dinuc- leoside monophosphates excepting GpG. In each case chemical shift and coupling constant data have been obtained for every proton in the molecule and this information has provided a detailed description of their conformations in solution.A similar exercise has been carried for the 2’-O-methylated dinucleoside monophosphate A,pA. The 31Pn.m.r. spectra of a number of mononucleotides and dinucleoside monophosphates have been investigated as a function of pH and correlated with their molecular stereochemistry .47 The field desorption technique allows molecular ions to be obtained in the mass spectra of unmodified dinucleoside mono phosphate^.^^ In addition the nature and intensity of the fragment ions may be used to deduce the base sequence. 39 R. J. Labotka T. Glonek and T. C. Meyers J. Amer. Chem. Soc. 1976,98,3699. 40 N. C.Seeman J. M. Rosenberg F. L. Suddath J. J. P. Kim and A. Rich J. Mol Biol. 1976,104 109; J. M. Rosenberg N. C. Seeman R. 0.Day and A. Rich ibid. p. 145. 41 B. Hingerty E. Subramanian,S. D. Stellman,T. Sato S. B. Broyde and R. Langridge Acta Cryst. 1976 B32.2998. 42 H. R. Wilson and J. Al-Mukhtar Nature 1976 263 171. 43 N. Camerman J. K. Fawcett and A. Camerman J. Mol. Biol. 1976 107,601. 44 T. R. Krugh J. W. Laing and M. A. Young Biochemistry 1976,15,1224. 45 C.-H. Lee F. S. Ezra N. S. Kondo R. H. Sarma and S. S. Danyluk Biochemistry 1976 15 3627. 46 H. Singh M. H. Herbut C.-H. Lee and R. H. Sarma Biopolymers 1976 15 2167. 47 P. J. Cozzone and 0.Jardetzky Biochemistry 1976,15,4853,4860. 48 H.-R. Schulten and H. M. Schiebel 2.analyt. Chem. 1976,280,139; Nucleic Acids Res.1976,3,2027. Biological Chemistry -Part (iii)Nucleic Acids 4 Oligonucleotidesand Polynucleotides The normal phosphotriester approach to the synthesis of oligodeoxyribonucleotides is essentially a two-step process involving separate and sequential 3’-and 5’-phosphorylation reactions. By using an improved phosphorylating agent consisting of a mixture of azolide and N-methy-imidazolide intermediates it is possible to combine these steps into a single reaction sequence.49 The modified procedure leads to an increase in overall yield to near quantitative and reduces the time required by a factor of four. A rapid new method” for synthesizing dinucleotides involves esterification of the 5’-phosphate group of the 5’-terminal nucleotide with the highly lipophilic protecting group TPTE (25) or the corresponding sulphone TPSE (26).Ph C0 SC H CH 0H Ph 3 COiCH2 CH 0H After formation of the internucleotide bond the dinucleotide product may be isolated in high yield by solvent extraction. The TPSE group can be subsequently removed by mild alkaline treatment. To remove TPTE it is first oxidized to TPSE. In the presence of ATP RNA ligase catalyses the joining of the 5’-phosphate of a donor oligoribonucleotide to the 3’-hydroxyl of an acceptor oligonucleotide. To prevent unwanted self-condensation of the donor oligonucleotide a 2’-0-(a -methoxyethyl) group may be introduced at its 3‘-terminus which can be easily removed after ligati~n.’~ In the presence of a variety of bivalent metal ions adenosine 5‘-phosphoroimidazolide condenses5* to give short oligoadenylic acids with chain lengths up to 5.With Pb2+ ions which are the most effective a 57% conversion into oligomers can be realized but the internucleotide linkages are mainly 2’-5’. Conditions have been perfected for sequencing oligodeoxyribonucleotides up to 15 residues long by mobility shift anal~sis.’~ This rapid method involves two- dimensional homochromatography of a partial exonuclease digest of the radioac- tively labelled oligonucleotide. The difference in mobility between consecutive spots on the chromatogram allows the sequence to be deduced directly. Oligonucleotides rich in guanine produced by digestion of RNA with pancreatic ribonuclease are difficult to isolate and sequence due to aggregation.After modification with kethoxals4 such oligonucleotides can be cleaved specifically at the A residues by U2 ribonuclease to give easily characterized fragments. This procedure generally allows their correct sequence to be determined without ambiguity and it has been used to resolve the structure of some refractory G-rich oligonucleotides from MS2 RNA. 49 P. Cashion K. Porter T. Cadger G. Sathe T. Tranquilla H. Notman and E. Jay Tetrahedron Letters 1976,3769. 50 K. L. Agarwal Y. A. Berlin H.-J. Fritz M.J. Gait D. G. Kleid R. G. Lees K. E. Norris B. Ramamoorthy and H. G. Khorana J. Amer. Chem. Soc. 1976,98,1065. 51 J. J. Sninsky J. A. Last and P. T. Gilham Nucleic Acids Res. 1976 3 3157. 52 H. Sawai J. Amer. Chem. SOC.,1976,98,7037.53 C.-P. D. Tu E. Jay C. P. Bahl and R. Wu Analyt. Biochem. 1976,7473. S4 W. Min Jou and W. Fiers F.E.B.S.Letters 1976,66 77. 384 R.J. H. Davies The interaction of the d-CpGpCpG duplex with actinomycin D and with ethidium bromide has been monitoredss by n.m.r. spectroscopy. Low-field resonances in the range -10 to -16 p.p.m. from sodium 4,4-dimethyl-4-silapentanesulphonate,are associated with the ring nitrogen protons of Hoogsteen and other non-classical base pairs as well as those of Watson-Crick base pairs. This finding arisess6 from an n.m.r. study of a variety of systems including the triple-stranded complexes of oligo-UlS and oligo-s4Uls with AMP and of 01igo-C~~ with GMP at acid pH. From a comparison of the thermal stabilities of the triple-stranded complexes of poly(C) with GMP and 8-amino-GMP it has been concludeds7 that the second poly(C) strand hydrogen-bonds in Hoogsteen fashion.A number of complexes of poly(A) with xanthine and its derivatives have been characterizedS* by equilibrium dialysis U.V. absorption and 0.r.d. measurements. For the first time the molecular structure of a single-stranded polynucleotide poly(C) has been determineds9 by X-ray fibre diffraction methods. Under neutral conditions poly(isoguany1ic acid) exists as a very stable four-stranded helix which is fully resistant to nuclease digestion.60 At pH 7 in O.OlM-NaCl poly(G) is claimed6' to exist as a single-stranded helix stabilized by stacking interactions which under- goes a co-operative thermal transition with T = 68 "C.Poly(06-methylguanylic acid) and poly(06-ethylguanylic acid) also show co-operative melting behaviour62 indicative of considerable secondary structure; these polymers do not complex with poly(C) or with poly(U). Poly(6-thioguanylic acid) has been prepared 63 from poly(2-amino-6-chloropurinylicacid). It forms a relatively unstable complex with poly(C) and on heating is converted into a copolymer of guanylic and 6-thioguanylic acids. Poly(2-aminoadenylic acid) forms both double and triple helices with poly(U) the thermal transitions of which can be clearly its interaction with poly(s4U) has also been in~estigated.~' Experiments related to the induction of interferon by helical polynucleotides have given new insight into polynucleotide displacement reactions.66 When a polynucleotide complex is mixed with another polynucleotide which is complementary to one of its components a displacement reaction will occur if a new complex can be formed which has higher thermal stability than the original one.The reaction is quite rapid being complete within 1h even at temperatures well below the T of the reactant helix. For example if the triple- stranded complex poly(A).2 poly(I) which has Tm=44"C is mixed with two equivalents of poly(C) double-stranded poly(I).poly(C) is produced which has T = 63 "C and a single strand of poly(A) is released. The more stable product helices are invariably better inducers of interferon than the reactant helices. 5s D. J. Patel Biopolymers 1976,15,533; D. J.Patel and L. L. Canuel Proc. Nut. Acad. Sci. U.S.A. 1976 73 3343. 56 N. R. Kallenbach W. E. Daniel jun. and M. A. Kaminker Biochemistry 1976 15 1218. 57 M. Hattori J. Frazier and H. T. Miles Biopolymers 1976 15 523. 58 R. J. H. Davies European J. Biochem. 1976,61 225. 59 S. Arnott R. Chandrasekaran and A. G. W. Leslie J. Mol. Biol. 1976,106,735. 60 T. GolaS M. Fikus Z. Kazimierczuk and D. Shugar EuropeanJ. Biochem. 1976,65 183. 61 H. Klump Biophys. Chem. 1976 5 359. 62 J. R. Mehta and D. B. Ludlum Biochemistry 1976,15,4329. 63 V. Armanath and A. D. Broom Biochemistry 1976,15,4386. 64 F. B. Howard J. Frazier and H. T. Miles Biochemistry 1976,15 3783. 65 C. Janion and K. H. Scheit Biochim. Biophys. Acta 1976,432 192. 66 E. De Clercq P. F. Torrence and B.Witkop Biochemistry 1976 15 717 724. Biological Chemistry -Part (iii) Nucleic Acids 5 Binding of Carcinogenic Hydrocarbons The molecular basis for the carcinogenic action of benzo[ ajpyrene and other aromatic polycyclic hydrocarbons which are widely distributed in the environment has posed a difficult problem for many years. Although many experiments have demonstrated their binding to DNA both in vitro and in vivo the nature of this interaction has remained obscure. Recently however considerable progress has been made in this area of cancer research and a plausible mechanism can now be advanced to account for the binding of benzo[a]pyrene to nucleic acids in vivo. It has been shown6' that the hydrocarbon is metabolized by the microsomal mixed- function oxidases of rat liver predominantly to the anti-benzo[a Ipyrene-diolepoxide (27).Significantly the major hydrocarbon-deoxyribonucleoside hydrolysis pro- duct obtained from DNA treated with the anti-diolepoxide (27) in vitro is chromatographically identical68 with that isolated from the DNA of rodent cells cultured in the presence of benzo[a]pyrene. Although the structure of this DNA adduct has not been established there is strong evidence to suggest that it might arise by reaction of the 2-amino group of guanine with the diolepoxide. When poly(G) is exposed to the diolepoxide (27) and subsequently hydrolysed a product may be A OH (27) isolated69 which is also obtained by hydrolysis of the nucleic acids from cells incubated with benzo[a]pyrene.This hydrocarbon-ribonucleoside hydrolysis pro- duct has now been positively identified7' as the N2-substituted guanosine derivative 0 I OH (28) S. K. Yang D. W. McCourt P. P. Roller and H. V. Gelboin Proc. Nut. Acad. Sci. U.S.A. 1976 73 2594. H. W. S. King M. R. Osborne F. A. Beland R. G. Harvey and P. Brookes Proc. Nut. Acad. Sci. U.S.A. 1976,73,2679. I. B. Weinstein A. M. Jeffrey K. W. Jennette S. H. Blobstein R. G. Harvey H. Kasai and K. Nakanishi Science 1976 193 592. A. M. Jeffrey K. W. Jenette S. H. Blobstein I. B. Weinstein F. A. Beland R. G. Harvey H. Kasai I. Miura and K. Nakanishi J. Amer. Chem. SOC.,1976,98,5714. R. J. H.Davies (28). Poly(G) also reacts with the syn-benzo[a]pyrene-diolepoxide (29)in a similar While the metabolic conversion of benzo[ alpyrene into the diolepoxide (27) followed by its reaction with the 2-amino-group of guanine evidently constitutes an important mechanism for its binding to nucleic acids the presence of several minor adducts in DNA hydrolysates,68 including one derived from the syn-diolepoxide (29) indicates that it is certainly not the only one.Whether diolepoxides are the major reactive metabolites formed from other carcinogenic hydrocarbons remains to be investigated. K-region epoxides were at one time considered to be likely candidates iE this respect but evidence is now accumulating to suggest that they do not play an important role in carcinogenesis. Nevertheless the K-region epoxide of 7,12-dimethylbenz[a]anthracenebinds covalently to poly(G) via the 2-amino- group of guanine.72 Four products have been isolated and characterized the two diastereomers of each of the adducts formed by reaction at the 5-position (30) and (30) R' = G R2= OH (31) R~=OH R~ = G Another observation of interest in this general context concerns the reaction between tetrakis(hydroxymethy1)phosphonium salts and g~anosine.~~ These salts which are representative of a class of compounds used commercially as flame retardants in certain fabrics react rapidly with the 2-amino-group of guanosine under neutral conditions to give the phosphine derivative (32).A thorough evaluation of their mutagenic and carcinogenic properties is clearly merited. (32) ribosyl 71 M. Koreeda P.D. Moore H. Yagi,H. J. C. Yeh andD. M. Jerina J. Amer. Chem.SOC.,1976,98,6720. 72 A. M. Jeffrey S. H. Blobstein I. B. Weinstein F. A. Beland R. G. Harvey H. Kasai and K. Nakanishi Proc. Nut. Acad. Sci. U.S.A. 1976 73 2311. 73 G. Loenwengart and B. L. Van Duuren Tetrahedron Letters 1976 3473. Biological Chemistry -Part (iii) Nucleic Acids 6 tRNA By using crystallographic refinement techniques similar to those applied to protein structures an improved model has been constructed for the monoclinic form of yeast tRNAPh" which is based on the electron density map at 2.5 A resolution. While confirming nearly all the structural assignments made previously this model affords a more accurate picture of the hydrogen-bonding network within the molecule which is described in Excluding the base-pairs in the double-helical stems 41 hydrogen bonds are listed almost half of which involve the ribose 2'-hydroxy-groups as donors and/or acceptors.Analysis of the structure has also brought to light important new conformational principles concerning both the structure of mononuc-leotide residues and the geometry of loops and bends in polynucleotide chains. In particular it is clear that the polynucleotide chain can adopt many more conforma- tions than are dictated by the 'rigid nucleotide' hypothesis. Of the 23 ribose moieties in non-helical regions other than the anticodon loop 10 have the C2'-endo pucker rather than the more usual C3'-endo pucker found in RNA double helices. The double-helical regions in tRNA have a smaller pitch than is observed for RNA in fibres and it appears that they may be stabilized by hydrogen-bonding between the 2'-hydroxy-group of one ribose and the 0-1' atom of its neighbour.A detailed account of the secondary and tertiary structure of the orthorhombic form of the same tRNA as discerned at 2.5 A resolution has been rep~rted'~ from Rich's laboratory. Their X-ray diffraction data at 2.7 A resolution have also been refined using different procedures by Sussman and Kim,76 to give a second model for this crystal form of yeast tRNAPhe. The atomic co-ordinates for these two models of the orthorhombic form have been compared with each other and with the preliminary co-ordinates published for the monoclinic form by the MRC group at Cambridge.It is concluded that all the models are practically identical with the greatest discrepancy occurring at the 3'-end of the molecule where the electron density is weak due to thermal motion. A similar exercise has been carried out by Sundaralingam and co-w~rkers,~~ who have independently determined the structure of the monoclinic form of yeast tRNAPhe at 3 8 resolution. Although their crystallo- graphic data are less extensive than those of the other groups they have made a detailed comparison of their model with the other three placing particular emphasis on the stereochemistry of the ribose-phosphate backbone. However it is perhaps questionable whether the sets of atomic co-ordinates currently available are suffi-ciently precise to justify firm conclusions regarding conformational differences between the various models.Results from both laser-Raman and high-resolution n.m.r. spectroscopy indicate that yeast tRNAPhe has the same structure in the crystalline state and in solution. The laser-Raman spectra of orthorhombic and hexagonal crystals of tRNAPhe show the same characteristic frequencies and intensities as the tRNA in The resonance positions of the hydrogen-bonded ring nitrogen protons in tRNA are 74 A. Jack J. E. Ladner and A. Klug J. Mol. Biol. 1976 108 619; Nature 1976 261 250. 75 G. J. Quigley and A. Rich Science 1976 194 796. 76 J. L.Sussman and S.-H. Kim Biochem. Biophys. Res. Comm. 1976,68 89; Science 1976,192 853. 77 C.D.Stout H. Mizuno J. Rubin T. Brennan S. T. Rao and M.Sundaralingam Nucleic Acids Res. 1976,3,1111. M.C. Chen R. GiegC R. C. Lord and A. Rich Biochemistry 1975,14,4385. 388 R.J. H.Davies determined almost entirely by ring-current effects which can be calculated very accurately. When this is done using the refined X-ray structure co-ordinates the close correspondence between the computed and observed low-field 'H n.m.r. spectra shows that the crystal and solution structures are virtually identi~al.'~ The quantitative determination of the number of secondary and tertiary base-pairs in tRNA molecules by n.m.r. spectroscopy has proved controversial. Before the occurrence of tertiary base-pairing was recognized n.m.r. measurements conve- niently gave an answer in accord with the number of base-pairs in the cloverleaf structure.The missing tertiary base-pairs were not detected primarily owing to inaccuracies in the proton integration caused by the lack of a satisfactory intensity standard. This difficulty has now been overcome80 by calibrating the integration against the number of aromatic protons in the molecule which is readily obtained from its sequence. Results for a number of tRNA molecules reveal that three or four resonances attributable to tertiary interactions can be detected provided a suffi-ciently high concentration of magnesium ions is present in the solution. A review" of the applications of n.m.r. spectroscopy in elucidating tRNA structure is available. The binding of magnesium ions to the native form of tRNAfMer1 from E. coli has been studied; there is one strong binding site which disappears when the tertiary structure unfolds and 26 weaker ones.82 At high magnesium ion concentrations the thermal unfolding of the tRNA is a two-state process in contrast with the sequential unfolding seen in the absence of magnesium.The kinetics of the unfolding process have been analysed by temperature-jump relaxation spectrometry. This technique has also been usedB3 to investigate the complex formed between yeast tRNAPhe and E. coli tRNAG'" which have the respective complementary anticodons GmAA and s2UUC. The complex dissociates lo6times more slowly than expected because the three base-pair helix is stabilized by being sandwiched between stacked bases. Two reviews concerned with the sequence structure and properties of tRNA have been published.84 Now that the structure of tRNA is so well defined the next step will be to correlate this structure with the various biological functions of tRNA.In this respect the determinationB5 of the crystal structure of a tyrosyl-tRNA synthetase enzyme at 2.7 A resolution is a very important development. About a dozen new primary sequences of tRNA have appeared this year. 5-Methoxyuridine has been identifiedB6 as a new minor base located in the first position of the anticodon in certain tRNAs from B. subfilis. The modified nucleoside Q" which is found in the tRNA of some animals has proved to be the most structurally complex nucleoside so far di~covered.~' It is in fact a mixture (33)of the P-D-galactoside and P -D-mannoside of the Q nucleoside.The elegant structure 79 G. T.Robillard C. E. Tarr F. Vosman and H. J. C. Berendsen Nature 1976,262 363. 80 P.H. Bolton and D. R. Kearns Nature 1976,262,423; P. H. Bolton C. R. Jones D. Bastedo-Lerner K. L. Wong and D. R. Kearns Biochemistry 1976,15,4370. S1 D.R. Kearns Progr. Nucleic Acid Res. Mol. Biol. 1976 18 91. 82 A.Stein and D. M. Crothers Biochemistry 1976,15 157 160. 83 H. Grosjean D. G. SOH and D. M. Crothers J. Mol. Biol. 1976,103 499. 84 A. Rich and U. L. RajBhandary Ann. Rev. Biochem. 1976,45,805;S.-H. Kim Bog. Nucleic Acid Res. Mol. Biol. 1976,17,182. 85 M. J. Irwin J. Nyborg B. R. Reid and D. M. Blow J. Mol. Biol. 1976 105 577. 86 K. Murao T. Hasegawa and H. Ishikura Nucleic Acids Res. 1976,3 285 1.87 H.Kasai K. Nakanishi R. D. Macfarlane D. F. Torgerson Z. Ohashi J. A. McCloskey H. J. Gross,and S. Nishimura J. Amer. Chem. Soc. 1976,98 5044. Biological Chemistry -Part (iii)Nucleic Acids I ribosyl R = @-D-galactosylor /3-D-mannosyl (33) determination achieved with only 0.6 mg of amorphous material indicates that the hexose residues are attached to the C-4 position of the cyclopentenediol ring. The modified nucleoside N’ (34) from E. coli tRNA is formed88 by enzymatic coupling Me I CHOH I NHCONHCH CH2OH ribosyl (34) of the threonine moiety of the minor base t6A with tris(hydroxymethy1)methylamine derived from tris buffer in the medium used to suspend the cells. The antineoplastic drug 5-azacytidine selectively inhibits enzymatic methylation at the 5’-position of cytosine.89 This effect which was detected by its action in reducing the 5-methylcytidine content of mouse liver tRNA shows that the modified components of nucleic acids provide potential targets for chemotherapeutic agents.A quantitative method for estimating the methylated bases in tRNA hydrolysates by high- resolution liquid chromatography has been described.” 7 RNA Sequence and Structure.-The RNA genome of bacteriophage MS2 which has now been completely sequenced,’ contains 3569 nucleotide residues of which 10.2% occur in untranslated segments. The RNA codes for three proteins the A protein the coat protein and a replicase subunit. An intact virus particle consists of one RNA molecule one A protein molecule and ca.180coat protein molecules. As the 88 H. Kasai K. Murao S. Nishimura J. G. Liehr P. F. Crain and J. A. McCloskey EuropeanI. Biochem. 1976,69,435. 89 L. W. Lu,G. H. Chiang D. Medina andK. Randerath Biochem. Biophys. Res. Comm. 1976,68,1094. D. B. Lakings T. P. Waalkes and J. E. Mrochek J. Chrornatogr.,1976,116 83. 390 R.J. H. Davies sequences of these proteins are also known the entire primary structure of the bacteriophage is established. A tentative hairpin-loop secondary structure has been proposed for the RNA and likened to a bouquet of flowers! The MS2 RNA sequence has been compared” with the partial sequences cur- rently available for the RNAs of the closely related bacteriophages R17 and f2. All the observed differences in their sequences can be accounted for by single base substitutions of which there are 28 in 854 nucleotides between MS2 and R17 and 11 in 442 nucleotides between MS2 and f2 RNA.During the course of this work a new mini-fingerprinting technique92 was developed for the analysis of enzymatic digests of 32P-labelled RNA. This combines high sensitivity with excellent resolution due to the pinhead size of the spots. An extraordinarily sensitive post-labelling method for sequencing non-radioactive RNA fragments has been described.93 Each oligonuc- leotide is first converted into the 3H-labelled 3’- terminal dialcohol which is then partially digested with endonuclease S1 to generate all possible intermediate chain lengths. Following their separation the 5’-terminal bases of these intermediate products are identified by 32P-labelling with polynucleotide kinase and subsequent digestion to mononucleotides.It is claimed that only 0.1-0.3 A,, unit of a tRNA is required to sequence all the fragments in a complete TI or ribonuclease A digest. Undoubtedly the simplest pathogenic infectious agents are the viroids which consist simply of RNA molecules having molecular weights of ca. lo5. They are responsible for certain plant diseases of economic importgnce such as the spindle tuber disease of potatoes but their mode of action remains a mystery because the RNA is far too small to code for its own replication. Viroids have now been identified94 as single-stranded covalently closed circular RNA molecules which exist as highly base-paired rod-like structures.The potato spindle tuber viroid RNA has been separated into three infectious forms one of which has been purified and characterized by oligonucleotide mapping.95 At elevated temperatures RNA can hybridize to double-stranded DNA in the presence of 70% formamide by displacing the identical DNA The stable R-loop structures so formed are readily visualized by electron microscopy and should facilitate the mapping and isolation of DNA sequences complementary to specific RNA species. It has been estimated that the rate of hydrolysis of an internucleotide 2’,5’-bond in a right-handed RNA triple helix is almost 900 times faster than that of a similar 3’,5‘-b0nd.~’ The greater hydrolytic stability of the 3’,5‘-linkage may explain its exclusive occurrence in natural RNAs.The sequence of a 179-nucleotide precursor molecule of the 5s ribosomal RNA of B. subtifis has been reported.98 In addition to the 116-nucleotide mature segment it contains an extra 21 nucleotides at the 5‘-end and an extra 42 at the 3’-end. A Y-shaped tertiary structure model has been for 5s RNA on the basis of 91 W. Min Jou and W. Fiers J. Mol. Biol. 1976 106,1047. 92 G. Volckaert W. Min Jou and W. Fiers Analyt. Biochem. 1976,72,433. 93 R. C. Gupta E. Randerath and K. Randerath Nucleic Acids Res. 1976 3,2895 2915. 94 H. L. Sanger G. Klotz D. Riesner H. J. Gross and A. K. Kleinschmidt Proc. Nut. Acad. Sci. U.S.A. 1976,73,3852. 95 R. P. Singh J. J. Michniewicz and S. A. Narang Canad. J.Biochem. 1976 54 600. 96 M. Thomas R. L. White and R. W. Davis Proc. Nut. Acad. Sci. U.S.A. 1976,73 2294. 97 D. A. Usher and A. H. McHale Proc. Nut. Acad. Sci. U.S.A. 1976,73 1149. 98 M. L. Sogin and N. R. Pace J. Biol. Chem. 1976,251 3480. 99 R. Osterberg B. Sjoberg and R. A. Garrett European J. Biochem. 1976,68,481. Biological Chemistry -Part (iii1Nucleic Acids small-angle X-ray scattering measurements. Now that the sequence of 16s ribosomal RNA is almost fully established that of 23s RNA is receiving increased attention. Already considerable progress has been made and substantial sequences from several parts of the molecule are known."' A particularly useful method for obtaining defined large fragments of the RNA is to digest the complexes formed between the RNA and some of the ribosomal proteins with ribonucleases.In favourable circumstances ribonucleoprotein particles are obtained which contain RNA sequences protected from digestion by association with the protein. In this way the binding site of the ribosomal protein L1 has been identified."' It is incorporated in a tract of 175nucleotides which has been almost entirely sequenced and lies between 550 and 1000 nucleotides from the 3'-end of the molecule. Ribonuclease digestion of intact 50s subunits of E. coli ribosomes gives two specific ribonucleoprotein particles."* One contains proteins L1 and L9. The other con- tains proteins L5 L18 and L25 associated with 5s RNA and a fragment of the 23s RNA which is located within the region 450 to 1000 nucleotides from the 3'-end.Terminal sequences of approximately 10and 20 nucleotides from the 5'-and 3'-ends of the 23s RNA are now known.lo3 These are remarkable in showing extensive complementarity both with each other and with certain regions of the 16s RNA. Reviews of the structure and function of ribosomes including their investigation by affinity labelling techniques have been published. lo4 The processing of tRNA ribosomal RNA and mRNA molecules has also been re~iewed.''~ mRNA and Viral RNA.-The tryptophan operon of E. coli contains five structural genes for the enzymes involved in tryptophan metabolism. Transcription of this operon into mRNA commences at a point 166 nucleotides before the initiation codon for the first of the five polypeptide chains specified by the structural gene sequence.This leader sequence at the 5'-end of the mRNA has now been deter- mined and shown to play an important part in regulating transcription of the structural genes.lo6 It contains an initiating AUG codon (positions 27-29) in a region which binds to ribosomes which is in phase with two successive termination codons at positions 120-125. These are followed by a tract of 12nucleotides which are all either G or C and then by eight consecutive U residues. When E.coli is grown in the presence of excess tryptophan seven out of eight mRNA chains initiated by RNA polymerase terminate in this U-rich region and are only ca. 145 nucleotides long. However under conditions of tryptophan starvation this attenuation of transcription is less frequent and more mRNA molecules containing the structural gene sequences are synthesized.The DNA sequence of 33 nucleotides immediately preceding the initiation site for transcription of the tryptophan operon mRNA has also been e~tablished.'~' loo C. Branlant J. Sriwidada A. Krol P. Fellner and J. P. Ebel Biochimie 1975 57 175. l01 P. Sloof R. Garrett A. Krol and C. Branlant European J. Biochem. 1976,70 447 and the following two papers. lo2 C. Branlant A. Krol J. Sriwidada and R. Brimacombe European J. Biochem. 1976 70,483. lo3 C. Branlant J. Sriwidada A. Krol and J. P. Ebel Nucleic Acids Res. 1976 3 1671. lo4 R. Brimacornbe K. H. Nierhaus R. A. Garrett and H. G. Wittman Progr. Nucieic Acid Res. Mol. Biol. 1976 18 1; E. Kiichler Angew.Chem. Internat. Edn. 1976,15 533. 1°5 R. P. Perry Ann. Rev. Biochem. 1976,45 605. lo6 K. Bertrand C. Squires and C. Yanofsky J. Mol. Biol. 1976,103,319,and the following five papers. lo' G. N. Bennett M. E. Schweingruber K. D. Brown C. Squires and C. Yanofsky Proc. Nut. Acad. Sci. U.S.A.,1976,73 2351. 392 R. J.H.Davies As many as one-third to one-half of the nucleotides in the mRNA molecules of higher organisms may be untranslated. These non-coding regions are located at the 5'-end of the mRNA and adjacent to the 3'-terminal poly(A) sequence. By sequenc- ing DNA transcripts of the mRNA 3'-terminal non-coding sequences up to 75 nucleotides in length have been determined for the rabbit and human a-and P-globin mRNAs a mouse immunoglobulin light-chain mRNA and chicken ovalbumin mRNA."' While the sequences immediately adjacent to the poly(A) tail show no sustained homology the sequence AAUAAA is found in all six mRNAs between 14 and 20 nucleotides away from the poly(A).Its significance is still unknown but it may be a signal for termination of transcription or a recognition site for some regulatory protein common to these and possibly all eukaryotic mRNAs. A tract of 89 nucleotides from the coding region of rabbit P-globin mRNA has also been sequenced.log Rabbit globin mRNA labelled to a very high specific activity with lZ5I has been used to identify the sequences which are protected from nuclease digestion when it binds to ribosomes.110 The RNA genome of influenza virus consists of eight distinct pieces of RNA which have been separated electrophoretically and characterized by oligonucleotide map- ping.'" The independent nature of the virus genes is believed to account for the high recombination frequencies observed in mixed infections and may be relevant to the periodic emergence of new pandemic strains of human influenza virus.The RNAs of several type C oncornaviruses which cause tumours in animals are dimeric molecules in which the two RNA subunits are held together non-covalently by an unusual and as yet undefined linkage structure located close to their 5'-ends. This has been revealed"* by electron microscopy of the RNA exploiting a new technique for visualizing the 3'-terminal poly(A) sequences. This depends on hybridizing them to poly(dT) sequences covalently attached to circular SV40 DNA molecules which are easily recognizable in electron micrographs.8 DNA Synthesis.-The experimental details of much of the work involved in the chemical synthesis of the biologically functional tyrosine suppressor tRNA gene mentioned in the Introduction have been published in the Journal of Biological Cherni~try."~ Eleven papers explain the strategy behind the synthesis of a DNA segment of 126 base pairs which contains the structural gene sequence for the tRNA precursor molecule and its experimental realization. A twelfth paper describes the synthesis of a further DNA duplex corresponding to an adjoining sequence of 23 nucleotides from the terminator region of the gene. The sequencing of the terminator region 108 N.J. Proudfoot and G. G. Brownlee Nature 1976,263 211; N. J. Proudfoot J. Mol. Biol. 1976,107 491; C. C.Cheng G. G. Brownlee N. H. Carey M. T. Doel S. Gillam and M. Smith ibid. p. 527. lo9 N. J. Proudfoot Nucleic Acids Res. 1976 3 1811. 110 S.Legon H.D. Robertson and W. Prensky J. Mol. Biol. 1976,106 23; S. Legon ibid. p. 37. 111 D.McGeoch P. Fellner and C.Newton Proc. Nat. Acad. Sci. U.S.A. 1976 73 3045. 112 W.Bender and N. Davidson Cell 1976,7 595 and the following paper. H. G. Khorana K. L. Agarwal P. Besmer H. Buchi M. H. Caruthers P. J. Cashion M. Fridkin E. Jay K. Kleppe R. Kleppe A. Kumar P. C. Loewen R. C. Miller K. Minamoto A. Panet U. L. RajBhandary B. Ramamoorthy T. Sekiya T. Takeya and J. H. van de Sande J.Biol.Chern.,1976,251 565 and the following eleven papers. Biological Chemistry -Part (iii) Nucleic Acids 393 and of the first 59 nucleotides in the promoter region of the gene has also been discussed.'l4 Another method of synthesizing genes is to produce a cDNA copy of a purified mRNA using a reverse transcriptase enzyme. This approach is of course much less time-consuming than chemical synthesis and does not require prior knowledge of the gene sequence. However it is applicable only to those DNA sequences which are transcribed into mRNA and does not permit the deliberate introduction of altered base sequences which is possible with Khorana's approach. By using reverse transcriptase in conjunction with DNA polymerase I and endonuclease S1 rabbit globin mRNA has been copied to give a synthetic gene of 580 base pairs."' This contains the complete sequence coding for the 6-globin polypeptide chain plus 40 untranslated nucleotides at its 5'-end and 110 untranslated nucleotides at its 3'-end.The gene has been successfully inserted into a bacterial plasmid DNA and shown to be stable during its amplification in E. coli. Employing somewhat different techni- ques all of which involve reverse transcription of the mRNA as the first step four other groups116 have constructed hybrid plasmid DNA molecules containing globin gene sequences and amplified them by cloning in bacteria. The lactose operator of E. coli which is the binding site for the regulatory lactose repressor protein consists of a DNA sequence of 21 base pairs.This DNA fragment has been synthesized by chemical and enzymatic method^."^ Two different linkage procedures have been used to insert the synthetic operator into a plasmid DNA. When E. coli bacteria are infected with the hybrid plasmid they synthesize the enzyme P-galactosidase in an uncontrolled manner (constitutively). This is because there are about 30 copies of the plasmid per bacterium and the operator sequences they contain titrate all the lactose repressor molecules normally present in the host cell. DNA molecules bearing 5'-terminal phosphate groups can be covalently joined to other DNA or RNA molecules by the action of RNA ligase."' Physical Studies,-The helix-coil transitions of a number of bacteriophage DNAs have been examined at very high re~olution.'~~ Instead of the single sharp peak expected for a single co-operative transition the differential melting curves for natural DNAs show hyperfine structure due to discrete sub-transitions known as thermalites which have a mean width of ca.0.3"C. This result is in accord with statistical mechanical theory which predicts that DNA denaturation involves the 114 T. Sekiya M. J. Gait K. Noris B. Ramamoorthy andH. G. Khorana J. Biol. Chem. 1976,251,4481;T. Sekiya R. Contreras H. Kupper A. Landy and H. G.Khorana ibid. p 5124. 115 A. Efstratiadis F.C. Kafatos A. M. Maxam and T. Maniatis Cell 1976,7,279;T. Maniatis S. G. Kee A. Efstratiadis andF. C. Kafatos ibid. 1976,8 163. I16 F.Rougeon P.Kourilski. and B. Mach Nucleic Acids Res.1975 2 2365; K. 0.Wood and J. C. Lee ibid. 1976,3,1961;T. H. Rabbitts Nature 1976,260,221;R. Higuchi G. V. Paddock R. Wall and W. Salser Proc. Nat. Acad. Sci. U.S.A.,1976 73 3146. 117 C. P. Bahl R. Wu K. Itakura N. Katagiri andS. A. Narang Proc. Nat. Acad. Sci. U.S.A.,1976,73,91; K. J. Marians R. Wu J. Stawinski T. Hozumi and S. A. Narang Nature 1976 263 744; H. L. Heyneker J. Shine H. M. Goodman H. W. Boyer J. Rosenberg R. E. Dickerson S. A. Narang K. Itakura S. Lin and A. D. Riggs ibid. p. 748. 118 T. J. Snopek A. Sugino K. L. Agarwal and N. R. Cozzarelli Biochem. Biophys. Res. Comm. 1976,68 417. 119 D. L. Vizard and A. T. Ansevin Biochemistry 1976,15,741;A. Wada H. Tachibana 0.Gotoh and M. Takanami Nature 1976,263,439;0.Gotoh Y. Husimi S. Yabuki and A.Wada Biopolymers 1976 15 655; Y. L. Lyubchenko M. D. Frank-Kamenetskii A. V. Vologodskii Y. S. Lazurkin and G. G. Gause jun. ibid. p. 1019. 394 R.J. H. Davies sequential co-operative melting of discrete regions of 500-1000 base pairs the stability of which is determined by their base composition and sequence. No less than 34characteristic thermalites have been detected in the melting of phage A DNA which contains 47000 base pairs. The secondary structure of DNA molecules can be frozen prior to electron microscopy by photochemical cross-linking of the complementary strands with 4,5',8-trirnethylp~oralen.'~~ This promising new technique has been used to test whether palindromic sequences in double-stranded DNA form cruciform arms in uivo and to visualize the hairpin loop secondary structure of single-stranded bacteriophage fd DNA.Knotted single-stranded DNA rings are produced'21 when the w protein of E. coli which removes superhelical turns from covalently closed double-stranded circular DNA molecules acts on the single-stranded circular form of bacteriophage fd DNA. A new enzyme DNA gyrase has been discovered'22 which introduces negative superhelical turns into covalently closed circular DNA. Sequence Studies.-The sequencing of bacteriophage 4x174 DNA which is a single-stranded molecule of ca. 5400 nucleotides is now almost complete. 123 Very rapid progress has been achieved by using the 'plus and minus' technique to determine sequences approximately 100 nucleotides in length which have been primed by various restriction endonuclease cleavage fragments hybridized to either the (+)or (-) strand of 4x174DNA as template.Sequence analysis of the gene D region has revealed the remarkable fact that genes D and E overlap so that gene E is located entirely within the gene D sequence. This means that two different protein sequences are specified by the same DNA sequence being translated in different reading frames. The complete sequences of gene G and of the intercistronic region which separates it from gene F have been established as well as most of the sequence of gene F.'24 Short sequences immediately beyond the sites of transcriptional termination can be determined by hybridizing the RNA transcript to its complementary DNA strand and then extending it by the action DNA p01ymerase.'~~The sequence of a DNA fragment of 28 base pairs from the origin of replication of SV40 DNA exhibits an unusually high degree of symmetry.'26 The internal 20 bases in each strand can loop out from the helix to form hairpin structures containing eight base pairs.A chemical method for the rapid sequencing of terminally labelled DNA strands up to 100 nucleotides in length has been developed by Maxam and Gilbert. The DNA chain is cleaved specifically at each of the four bases in turn to generate labelled fragments of all intermediate chain lengths which are then fractionated according to molecular weight by gel electrophoresis. Specific cleavage at A or G is achieved by methylation and subsequent acid hydrolysis under appropriate conditions and T.R. Cech and M. L. Pardue Proc. Nut. Acad. Sci. U.S.A. 1976 73 2644; C.-K. J. Shen and J. E. Hearst ibid. p. 2649. L. F. Liu R. E. Depew and J. C. Wang J. Mol. Biol. 1976 106 439. l2* M. Gellert K. Mizuuchi M. H. Odea and H. A. Nash Proc. Nut. Acud. Sci. U.S.A.,1976,73 3872. l23 B. G. Barrell G. M. Air and C. H. Hutchison Nature 1976 264 34. 124 J. C. Fiddes J. Mol. Biol. 1976,107 1; J. Sedat E. Ziff and F. Galibert ibid. p. 391; E. H. Blackburn ibid. p. 417; G. M. Air ibid. p. 433; G. M. Air E. H. Blackburn A. R. Coulson F. Galibert,F. Sanger J. W. Sedat and E. B. Ziff ibid.,p. 445; G. M. Air F. Sanger and A. R. Coulson ibid. 1976,108,519. 125 M. Rosenberg B. De Crombrugghe and R. Musso Proc. Nut. Acud. Sci. U.S.A.1976 73 717. 126 E. Jay R. Roychoudhury and R. Wu Biochem. Biophys. Res. Comm. 1976.69.678. Biological Chemistry -Part (iii)Nucleic Acids 395 cleavage at C and T is achieved by reaction with hydrazine. Although full details of the method have not yet been published it has been used in the sequencing of two small restriction cleavage fragments from SV40 DNA127 and in establishing sequ- ences of 42 and 62 base pairs from a cloned segment of histone DNA.128 The latter piece of work forms part of a very impressive set of studies in which the arrangement of the histone genes in sea urchin DNA has been defined. The DNA from two species of sea urchin has been examined. In one case purified mRNAs correspond- ing to each of the histone proteins were isolated and hybridized to restriction fragments of the histone DNA.129 In the other plasmid-cloned fragments of histone DNA were characterized by sequence analysis as well as by hybridization to histone mRNA In both species the tandemly repeated clusters of coding sequences for the histones all lie on the same strand and are transcribed in the order H4 H2B H3 H2A and H1.They are separated by spacer regions which have been clearly delineated by electron microscopy. 13' Restriction endonucleases have been detected in about one third of the bacterial strains which have been screened for their activity. The recognition sites of several of these enzymes have been determined in the past year and they generally consist of a symmetrical sequence of four to eight base pairs within which cleavage of the DNA occurs.An interesting exception to this rule is provided by a restriction endonuc- lease from H.parahaemolyticus which produces staggered cuts in DNA at some AT base pairs. The sequences immediately surrounding the cleavage sites bear no apparent relationship to one another but eight or nine base pairs to one side of each cleavage site the common sequence iE$EE is The antibiotics distamycin A and actinomycin D have been reported to protect DNA from cleavage by certain restriction endonucleases. 133 Recombinant DNA.-The construction of hybrid plasmids which contain either globin DNA sequences or the synthetic lactose operator has already been described.' 15-'17 In other experiments a DNA segment incorporating a leftward operator of bacteriophage A has been inserted into a defective SV40 genome,134 and a piece of E.coli DNA that controls cell division and capsular polysaccharide synthesis has been c10ned.l~' The requirement of an E. coli mutant for histidine as a growth factor has been abolished by integrating into its chromosome a segment of yeast DNA which-is believed to code for a functional copy of the enzyme which is lacking in the mutant.136 This has been achieved through the agency of a hybrid A phage containing the yeast DNA fragment. A collection of hybrid plasmids rep- resentative of the entire E. coli genome has been prepared.'37 127 M. Ysebaert F. Thys A. Van de Voorde and W. Fiers Nucleic Acids Res. 1976 3 3409. 128 I. Sures A. Maxam R. H.Cohn and L. H. Kedes Cell 1976,9,495. 129 K. Gross E. Probst W. Schaffner and M. Birnstiel Cell 1976 8 455 and the following two papers. 130 R. H. Cohn J. C. Lowry and L. H. Kedes Cell 1976,9 147. 131 M. Wu D. S. Holmes N. Davidson R. H. Cohn and L. H. Kedes Cell 1976,9,163;R. Portmann W. Schaffner and M. Birnstiel Nature 1976,264 31. 132 D. Kleid Z. Humayun A. Jeffrey and M. Ptashne Proc. Nut. Acad. Sci. U.S.A. 1976,73 293. 133 V. V. Nosikov E. A. Braga A. V. Karlishev A. L. Zhuze and 0.L. Polyanovsky Nucleic Acids Res. 1976,3,2293. 134 A. L. Nussbaum D. Davoli D. Ganem and G. C. Fareed Proc. Nut. Acad. Sci. U.S.A. 1976,73,1068. 135 P. E. Berg R. Gayda H. Avni B. Zehnbauer and A. Markovitz Proc. Nut. Acad. Sci. U.S.A. 1976,73 697. 136 K. Struhl J.R. Cameron and R. W. Davis Proc. Nut. Acad. Sci. U.S.A. 1976,73 1471. 137 L. Clarke and J. Carbon Cell 1976 9 91. 396 R.J. H.Dauies Chromatin Structure.-Further progress has been made in defining the structure of the nucleosome subunits and their organization within chromatin. The digestion patterns observed when chromatin is treated with a variety of nucleases differ widely but two general conclusions can be drawn. One is that the nuclease-sensitive sites in chromatin occur at multiples of a minimum interval of 10 base pair^.'^'.'^^ The second is that nucleosomes as usually prepared consist of a nuclease-resistant core particle in which two molecules of each of the histones H2A H2B H3 and H4 are associated with ca. 140base pairs of DNA attached to a DNA segment of ca.50 base pairs which is more susceptible to nuclease attack. 139-'42 There is evidence to suggest that this terminal stretch of 50 base pairs is associated with the histone Hl,I4l which appears to play an important role in the condensation of the chromatin subunits into a higher order In an exciting new development electron microscopy and X-ray diffraction analysis'43 have shown that under certain condi- tions chromatin filaments may condense into a tightly packed supercoil or solenoidal structure having a pitch of about 11nm and outer diameter of 30-50 nm which is stabilized by histone H1. Neutron diffraction indicate that a similar coiled structure can be adopted by the nucleosomes in fibres prepared from chromatin depleted of histone H1.138 C. R. Cantor Proc. Nut. Acad. Sci. U.S.A. 1976 73 3391. 139 B. Sollner-Webb R. D. Camerini-Otero and G. Felsenfeld Cell 1976 9 179. l40 A. L. Olins R. D. Carlson E. B. Wright and D. E. Olins Nucleic Acids Res. 1976,3 3271. 141 A. J. Varshavsky V. V. Bakeyev and G. P. Georgiev Nucleic Acids Res. 1976,3,477;J. P. Whitlock jun. and R. T. Simpson Biochemistry 1976,15,3307. 142 M. Bellard P. Oudet J.-E. Germond and P. Chambon European J. Biochern. 1976 70 543. 143 J. T. Finch and A. Klug Proc. Nat. Acad. Sci. U.S.A. 1976 73 1897. 144 B. G. Carpenter J. P. Baldwin E. M. Bradbury and K. Ibel Nucleic Acids Res. 1976 3 1739.

ISSN:0069-3030    

DOI:10.1039/OC9767300375

出版商:RSC    

年代:1976

数据来源: RSC

摘要:

14 Biological Chemistry Part (iv) Alkaloids By D. G. BUCKLEY Chemistry Department Queen Mary College Mile End Road London El 4NS 1 Introduction In the three years since alkaloids were last reviewed in Annual Reports a great deal of new work has been published and for a comprehensive survey the reader is referred to Volumes 5 and 6 of the Specialist Periodical Reports on the Alkaloids which cover the period July 1973 to June 1975.’#* Biosynthetic aspects are also treated in the companion on biosynthesis and these include a tabular survey of all tracer incorporations into alkaloids reported during 1973 and 1974. The period covered for this short review is 1974-1976 inclusive. 2 Pyridine and Piperidine Alkaloids The details of the isolation and structural elucidation of the macrocyclic spermidine alkaloid oncinotine (l),and the structurally related bases neo-oncinotine and iso-oncinotine have been published.’ The synthesis of (k)-oncinotine (1) was reported subsequently,6 the key step being the formation of the macrocyclic lactam by treatment of the appropriate amino-acid chloride precursor with triethylamine at high dilution.‘The Alkaloids’ ed. J. E. Saxton (Specialist Periodical Reports) The Chemical Society London 1975 Vol. 5. 2 ‘The Alkaloids’ ed. M. F. Grundon (Specialist Periodical Reports) The Chemical Society London 1976 Vol. 6. 3 ‘Biosynthesis’ ed. T. A. Geissman (Specialist Periodical Reports) The Chemical Society London 1975 VOl. 3. ‘Biosynthesis’ ed. J. D. Bu’Lock (Specialist Periodical Reports) The Chemical Society London 1976 VOl.4. A. Guggisberg M. M. Badawi M. Hesse and M. Schmid Helv. Chim.Acta 1974 57,414. F. Schneider K. Bernauer A. Guggisberg P. Van den Broek M. Hesse and H. Schmid Helv. Chim. Acta 1974 57 434. 397 398 D. G.Buckley Several new examples of spiropiperdine alkaloids have been isolated and they are related structurally to histrionicotoxin (2) and dihydrohistrionicotoxin (3) differing from these bases only in the nature of the 2-C and 7-C4 ~ide-chains.~ These alkaloids are of value in studies of ion conductance in electrogenic membranes; the nature of the side-chain is important in connection with cholinolytic activity or antagonism to the transport of sodium and potassium ions through such mem- brane~.~ Several stereocontrolled syntheses of (*)-perhydrohistrionicotoxin (4)'-'' and the naturally occurring (*)-octahydrohistrionicotoxin (5)8,9 have been described.cis (2) R' = R2= CH=CHCGCH (3) R' =CH2CH=C=CH2; R2=CH=CHCrCH (4) R' = R2=n-C4H9 (5) R' = R2=CH2CH2CH=CH2 C labelling has been used in studies of alkaloid biosynthesis with notable success recently and a good exampie is the structural and biosynthetic investigations on tenellin (6). First 13Cn.m.r. was used in conjunction with biosynthetic labelling of tenellin to provide valuable insight into the structure of this metabolite of Beauvaria species.' ' Second feeding experiments with putative precursors singly labelled with 13C led to the conclusion12 about the origins of the carbon skeleton shown in Scheme 1; C-15 and C-16 arise from methionine.Of note is the fact that C-1 of phenylalanine appears at C-4 of tenellin and C-2 at C-6. Incorporation of [1,2-'3C2]acetate gave tenellin with the expected satellite resonances due to I3C-l3C spin-spin coupling from which the intact two-carbon acetate-derived units could be discerned (see Scheme 1). Scheme1 7 T. Tokuyama K. Uenoyama G. Brown D. W. Daly and B. Witkop Helv. Chim. Acta 1974,57,2597. 8 M. Aratani L. V. Dunkerton T. Fukuyama Y. Kishi H. Kakoi S. Sugiara and S. Inone J. Org. Chem. 1975,40,2009. 9 T. Fukuyama L. V. Dunkerton M. Aratani and Y. Kishi J. Org. Chem. 1975,40 2009. 10 E. J. Corey J. F. Amett and G. N. Widiger J. Amer. Chem.Soc. 1975 97,430. A. G. McInnes D. G. Smith C.-K. Wat L. C. Vining and J. L. C. Wright J.C.S. Chem. Comm. 1974 281. 12 A. G. McInnes D. G. Smith J. A. Walter L. C. Vining and J. L. C. Wright J.C.S. Chem. Comm. 1974 282. Biological Chemistry -Part (iv) Alkaloids The general biosynthetic routes to the tobacco alkaloids nicotine (7) nornicotine (8) and anabasine (9) are fairly well established although the biosynthesis of the closely related bases anatabine (10) and a$-dipyridyl (1 1) has been investigated only re~ent1y.I~ The results suggest that (10) and (11)arise from precursors derived from nicotinic acid only and the authors suggest that dimerization of a dihyd- ropyridine takes place with subsequent elaboration to anatabine (10) and a$-dipyridyl (11)(Scheme 2).(7) R=Me (8) R=H 1 3 @-Phenethylamines and Isoquinoline Alkaloids Rubesamide (12) a p -phenethylamine derivative of cyclopropanecarboxylic acid has been isolated from the root bark of the Ghanaian tree Fuguru rubescens; the assigned structure (12) was confirmed by synthe~is.’~ (12) Another novel structure is possessed by macrostomine (13) an alkaloid from Pupaver macrostomum.” The structure was assigned on the basis of spectroscopic l3 E. Leete and S.A. Slattery J. Amer. Chem. SOC., 1976 98 6326. l4 B. A. Dadson and A. Minta J.C.S. Perkin I 1976 146. l5 V. A. Mnatsakanyan V. Preininger V. Simanek A. Klasek L. Dolejs and F. Santavy Tetrahedron Letters 1974 851. 400 D.G.Buckley (13) analysis and the (S)-configuration was deduced from comparison of its Cotton effect with those of (S)-(-)-nicotine and (S)-(-)-brevicolline.Further attention has been given to the electro-oxidative preparation of mor-phinandien~nes.'~*~' It has been proposed that at low potentials the amine func- tionality anchimerically assists the coupling (Scheme 3).l6 Cathodic cyclization of 1-OMe OMe "'"a \ \ Me0 Me0 / OMe OMe Ie 'OMe 'OMe Me0 Me0 MC 'Me Me0 OMe OMe Scheme3 (0-iodobenzyl)isoquinoliniummethiodides e.g. (14),has been reported to yield the corresponding aporphines e.g. (15) in high yield after catalytic hydrogenation. This sequence represents one of the most efficient direct routes to aporphines to date.18 16 L.L. Miller F. R. Stermitz J. Y.Becker and V. Ramachandran,J. Amer. Chem. SOC. 1975,97,2922. 17 T. Kametani K. Shishido and S. Takano J. Heterocyclic Chem. 1975,12 305. 18 R. Gottlieb and J. L. Neameyer J. Amer. Chem. SOC.,1976,97 7108. Biological Chemistry -Part (iv) Alkaloids (14) (15) The tricyclic base (-)-(16)? a key intermediate in the synthesis of various ipecacuanha alkaloids has been synthesized from (+)-(17)? the ethyl ester of cincholoipin (Scheme 4).l9 . .. y: '-C0,Et k '-C0,Et vii (16) Reagents:i 3,4-dimethoxyphenacyI chloride K,CO, benzene; ii NaBH, EtOH; iii Hg(OAc), edta 1 % aq. HOAc; iv Pd/C H2 EtOH 70% aq. HCIO,; v IN-NaOH EtOH 20°C; vi 10% HCI boiling; vii EtOH HCl 25 "C; viii POC13 toluene; ix PtO, H, EtOH.Scheme4 The cryptostyline alkaloids e.g. (-)-cryptostyline-I (1S) are the first isoquinoline alkaloids to be isolated from natural sources with an aryl group at C-1 which makes i9 T. Fujii and S. Yoshifuji Tetrahedron Letters 1975 73 1. 402 D. G.Buckley them a group of bases of some biosynthetic interest. The skeleton apart from the aryl substituent arises from a p-phenethylamine in the normal way,2o and the c& unit seems to be derived from an aromatic aldehyde derived by way of dopamine.21 The pathway so far delineated is broadly similar to the one deduced in detail for the cactus alkaloids.22 In spite of extensive and fruitful studies on the biosynthesis of benzylisoquinoline alkaloids research rather than speculation on the nature of the molecule which condenses with dopamine to give the benzylisoquinoline skeleton had remained neglected until recently.Evidence has now been provided for the pathway shown in Scheme 5; the pathway illustrated represents the conclusions of studies using Papaver orientale seedlings and latex23 and P. sornniferiurn Not only was norlandanosoline (22) labelled by [1-I4C,2-3H]dopamine (without change in isotope ratio) but also the previously unknown amino-acid (20),23 which was isolated when inactive material was used as carrier. Further evidence implicating (20) as an intermediate in isoquinoline biosynthesis comes from the efficient incorporation of labelled (20) into (22),23 and from the specific incorporation of labelled (20) into morphine (23).24 Oxidative decarboxylation of (20) affords (21) which was found to act as a precursor for morphine.24 These observations amongst suggest that the amino-acid (20) and the imine (21) are intermediates in the biosynthesis of the benzylisoquinoline bases.Amongst the alkaloids produced by Stephania japonica Miers are the biosyntheti- cally intriguing bases hasubanonine (24) and protostephanine (25). Attempts to understand how these bases are formed in vivo have long been frustrated although some progress has now been made.25 [2-14C]-Labelled tyrosine dopa tyramine and dopamine were incorporated into both alkaloids without randomization of label. The detailed results show (i) that both alkaloids are constructed from two C6-C2 units for which tyrosine is the source and (ii) that only one unit i.e.the one which generates ring cwith its attached ethanamine residue is labelled by [2-'4C]tyramine [2-14C]dopamine and [2-14C]dopa. The extent to which this latter p-phenethylamine unit is hydroxylated and methylated before combination with the other C6-C2 unit was examined by feeding the phenethylamines (26)-(29) to S. japonica. The bases (26) and (27) but not (28) and (29) acted as precursors for hasubanonine (24) and protostephanine (25) from which it is clear that it is the phenethylamine (27) which is involved in coupling with the other c&2 unit. These results give sets of possible isoquinoline and bisphenethylamine precursors the roles of which in hasubanonine and protostephanine biosynthesis have yet to be exp- 10red.~~ A new generally applicable synthesis of the proaporphine alkaloid (*)-glaziovine (30) involves a straightforward approach to the amine (31) which is then diazotized to give the o-amino-oxide (32) under alkaline conditions; a fast photo-cyclization 2o S.Agurell I. Granelli K. Leander B. Liining and J. Rosenblom Acta Chem. Scand. 1974 B28,239. 21 S. Agurell I. Granelli K. Leander and J. Rosenblom Acta Chem. Scand. 1974 B28,1175. 22 For reviews see J. Lundstrom Acta Pharm. Suecica 1971,8,275;R. B. Herbert in 'The Alkaloids' ed. J. E. Saxton (Specialist Periodical Reports) The Chemical Society London 1971 Vol. 1,p. 16; 1973 Vol. 3 p. 16. 23 M. L. Wilson and C. J. Coscia J. Amer. Chem. SOC.,1975 97 431. 24 A. R. Battersby R. C. F. Jones and R.Kazlauskas Tetrahedron Letters 1975 1873. 25 A. R. Battersby R.C. F. Jones R. Kazlauskas C. Poupat C. W. Thornber S. Ruchirawat and J. Staunton J.C.S. Chem Comm. 1974,773. Biological Chemistry -Part (iv1Alkaloids HO Tyrosine R =H Dopa R = OH H02C OH OH (20) OH (19) / Ho / 0@NMe HO / Scheme5 (26) R=H (28) R'=H; R2=Me (27) R=Me (29) R' = Me; R2= H 404 D. G.Buckley Me0 / MeomNMe HO NH2 CH2 0 0 H°FMe OH M-0e o w M e N' CH2 OH OH (32) ensues on irradiation of the intermediate (32) to give the proaporphine (*)-(30) in 45% yield [from (3 1)].26 Recently reported" studies on the biosynthesis of (-)-ophiocarpine (33) demon-strated that hydroxylation of the (-)-tetrahydroberberine cf.(39 occurs as the final step and furthermore that it proceeds with retention of configuration i.e. that stereospecific removal of the pro-R-hydrogen atom occurs to give (-)-(33). The highly stereoselective transannular cyclization of the trans-dibenzazacine (34) and its [13-3H] derivative was shown to provide an efficient route for the synthesis of the (*)-[13w3H]-and (*)-[ 13p-3H]-tetrahydroberberines,(35) and (36) respectively. (33) R' =H; R2= OH (34) (35) R' =3H;R2 = 'H (36) R' = 'H; R2= 3H The first known in vim conversion of berberine (37) into the phthalideiso- quinoline alkaloids (*)-a-hydrastine (38) and (*)-P-hydrastine is accomplished by an efficient route which may emulate in part the biogenetic process.28 The key to 26 C.Casagrande and L. Canonica J.C.S. Perkin I 1975,1647. 27 P.W. Jeffs and J. D. Scharver J. Amer. Chem. SOC.,1976,98,4301. 28 J. L.Moniot and M. Shamma J. Amer. Chem. SOC.,1976,98,6714. Biological Chemistry-Part (iv) Alkaloids 405 the conversion was the isolation of a novel oxidation dimer designated oxybis- berberine from the ferricyanide oxidation of (37).** This dimer was cleaved in methanolic hydrogen chloride to give (37) and 8-methoxyberberinephenolbetaine (39). Compound (39) may be regarded as a masked ester and hydrolysis gave a secondary amino-ester which was methylated with methyl iodide and the product was immediately reduced to give a 1:2 mixture of (&)-a-hydrastine (38)and (*)-P-hydrastine in high overall yield.'OMe (37) R'=R~=H;X=CI (38) (39) R' =OMe; R2 = 0-;no X- 4 Erythrina Alkaloids The Erythrina alkaloids are known to arise from the benzylisoquinoline (S)-N-norprotosinomenine (40) via the dibenzanonine (41) and erysodienone (42).29 t- NH Me0 Hod i OH OMe (41) OMe Recent have shown that only (-)-erysodienone which has the (5s)-chirality of the natural alkaloids is a precursor for erythraline (43) and a-and P-erythroidine (46). The conversion of (S)-N-norprotosinomenine (40)into (5s)-erysodienone (42),involves formally at least an inversion of chirality. However the chirality of (40) may well be lost in viuo for it was found that the biosynthetic intermediate (41) prepared by chemical reduction from chiral erysodienone (42) underwent very rapid racemization at room temperature.Further experiments have established the aromatic Erythrinu alkaloids as pre- cursors of the lactonic bases (46);satisfactory incorporations of the bases (42),(44) and (45) have been demonstrated to occur without ~crarnbling.~' 29 D. H. R. Barton C. J. Potter and D. A. Widdowson J.C.S. Perkin I 1974,346; R. B. Herbert in ref. 2 p. 25. 30 D. H. R Barton R. D. Bracko C. J. Potter and D. A. Widdowson J.C.S. Perkin I 1974,2278. 406 D. G. Buckley Me0 0 Me0 (42) (43) R1-R2 = CH2 (44) R1 = H; R2= Me (45) R'=R~=H 5 Terpenoid Indole Alkaloids A technique which must be certainly now be regarded as established in its applicabil- ity to the complex indole alkaloids is 13Cn.m.r.spectros~opy;~~ indeed a recent revision of the structure of vindolinine from (47) to (48)32would have been difficult (47) Incorrect Structure (48)Vindolinine to achieve simply by any chemical or other spectroscopic methods. Because it has been found that the 13C chemical shifts for carbons in typical indole alkaloid environments have reliably characteristic values a selection of data from those so far available on typical alkaloids derivatives and simple model compounds has been collected recently in a convenient form.31 An interesting example of asymmetric induction has been used in a new biogenetic-type synthesis of (-)-tetrahydroharman and (-)-(49) from L-try~tophan;~~ the synthesis of (-)-(49) is outlined in Scheme 6.Apparently the Pictet-Spengler closure is stereospecific and affords the 1,3-cis-isomer (50); removal of the unwanted carboxyl derivative is achieved in good yield and without epimerization at C-1 by NaBH reduction of an a-aminonitrile. This synthetic approach may well find application in other areas. The synthesis of ellipticine (51)continues to attract considerable attention owing to the reported anti-neoplastic activity of the alkaloid and much new work has been Scheme 7 illustrates one of the new approaches35 which together with a variant reported simultaneously involves the formation of the C-7-C-19 or possibly the C-19-C-20 bond. 31 J. A. Joule in ref. 1 pp. 184-191. See also A. Ahond A.-M. Bui P. Potier E. W. Hagaman and E. Wenkert J. Org. Chem.1976,41 1878. 32 A. Ahond M.-M. Janot N. Langlois G. Lukacs P. Potier P. Rasoanaivo M. Sangare N. Neuss M. Plat J. Le Men E. W. Hagaman and E. Wenkert J. Amer. Chem. SOC.,1974,96,633. 33 H. Akimoto K. Okamura M. Yui T. Shiroiri M. Kuramoto Y. Kikugawa and S. Yamada Chem. and Pharm. Bull (Japan) 1974 22 2614. 34 J. E. Saxton in ref. 2 pp. 229-231. 35 R. Besselikvre C. Thal H. P. Husson and P. Potier J.C.S. Chem. Comm. 1975 90. Biological Chemistry-Part (iv) Alkaloids 407 o-PCONH~ %ONH* \ I 1 NH,,HCI i \ I I N N-H H H' (-)-(49) Reagents i CI(CHJ,CHO H,O-MeOH; ii POCL,-C,H,N-DMF; iii NaBH, EtOH-C,H,N. Scheme6 Me Me / rl Me Me Ellipticine (51) Reagents i MeI; ii NaBH,; iii KOBul-DMSO; iv MeCH &Me,OAc AcOH; v Pd-C decalin.Scheme7 408 D. G.Buckley Two new iboga alkaloids ibophyllidine (52) and iboxyphylline (53) have been isolated from Tabernanthe iboga and T. Subsessilis and have been shown to be members of a new iboga sub-gr~up.~~ A consideration of chemical and spectro- scopic data led to their structural assignments and the structure of (53) was confirmed by X-ray analysis. This new sub-group may possibly arise as shown in Scheme 8.36After construction of the normal iboga skeleton enzymic oxidation to the cation radical (54) could then lead to cleavage of the C-20-C-21 bond to give (54a). Further oxidation would lead to (54b) which could either undergo a Mannich ring-closure to yield the precursor of (53) or suffer hydrolysis to (54c) which could then be elaborated to give (52).*I8 19 22 17 15 19 22 17 A Corynanthe-Iboga type Strichnos type (54) H \ \ N 0 OMe (52) Ibophyllidine (53) Iboxyphylline Scheme8 Macrolidine (55) from the heartwood of Adina rubescens is a new glycosidic indole alkaloid in which the terminal primary alcohol function in a 5-carboxyisovincoside derivative has formed a novel macrocyclic lactone ring with the 36 F. Khuong-Hua M. Cesario J. Guilhem and R. Goutarel Tetrahedron 1976 32 2539. Biological Chemistry -Part (iv)Alkaloids retained tryptophan carboxy-group.37 The structure was deduced from the spectra of macrolidine and its tetra-acyl derivatives and was confirmed by reaction of macrolidine tetra-acetate with methanolic sodium methoxide followed by re-acetylation which gave the known methyl 3a,5a-tetrahydrodesoxycordifoline penta-acetate (56).H H' H (55) (56) The intriguing tryptophan derivative trichotomine (57),isolated38 from the fruit of Clerodendron trichotornurn is a novel type of blue pigment. Chemical and spectros- copic evidence led to the structure (57)38* which was confirmed 38b by an X-ray analysis of the NN'-di-p-bromobenzoyl derivative. Interestingly although there must be extensive conjugation throughout the system the two indole rings are not in the same plane but at a dihedral angle of 38.6".Natural trichotomine has been synthesized (Scheme 9)" starting with L-tryptophan methyl ester and succinic H 0 HO,C (57) Trichotomine Reagents i succinic anhydride-PhH-heat; ii CH,N,; iii 200 "C; iv P,O,-PhH-heat; v -90 OC-0,-Bu"0H; vi 1N-KOH-MeOH-Et,O.Scheme9 37 R. T. Brown and A. A. Charalambides J.C.S. Chem. Comrn. 1974,553. 38 (a)S. Iwadare Y. Shizuri K. Sasaki and Y. Hirata Tetrahedron Letters 1974 1051; (6)K. Sasaki S. Iwadare and Y. Hirata ibid. p. 1055; (c)S.Iwadare Y. Shizuri K. Yamada and Y. Hirata ibid.,p. 1177. 410 D. G.Buckky anhydride components which may well also represent the biosynthetic precursors of the pigment. Cyclization to (58) was followed by a remarkably easy oxidative dimerization to the diester which was readily hydrolyzed to the pigment itself. 6 Terpenoid Bases The total synthesis of napelline (59) has now been completed by the Wiesner The recent work 39a,b describes the synthesis of the racemate (60) from the pentacyclic intermediate (6l) and the conversion of lucidusculine (62) into the identical but optically active derivative (60).Using this optically active intermediate (60) as a relay the synthesis of napelline was completed. OH 0 (59) Napelline ?H The total synthesis of talatisamine (63) has been accomplished by way of the atisine-type intermediate (64);a key step is the rearrangement of an atisine skeleton cf. (64) to a lycoctonine skeleton cf. (63).40This type of rearrangement has been proposed for the biogenesis of alkaloids possessing the lycoctonine skeleton and Johnson and O~erton~~ have previously reported studies and Ayer and De~hpande~~ of this process. The synthesis is summarised as (64)+(74)in seq~ence.~' A new diterpene alkaloid delphisine has been isolate from the seeds of Delphinium staphisagra.Chemical and spectroscopic studies indicated it to be a member of the aconitine-type alkaloids and an X-ray crystallographic study of delphisine hydrochloride revealed its structure to be (75).43 This definitive study has 39 (a)K. Wiesner Pak-tsun Ho and C. S. J. Tsai Canad. J. Chem. 1974,52,2353;(b)K. Wiesner Pak-tsun Ho C. S. J. Tsai and Yin-Kuen Lam ibid. p. 2355; (c) S. W. Pelletier and S. W. Page in ref. 1 pp. 235-238. 40 K. Wiesner T. Y. R. Tsai K. Huber and S. E. Bolton J. Amer. Chem. Soc. 1974,96 4990. 41 J. P. Johnston and K. H. Overton J.C.S. Perkin I 1972 1490. 42 W. A. Ayer and P. D. Deshpande Canad. J. Chem.1973,51,77. 43 S. W. Pelletier W. H. De Camp S. D. LajSik Z. Djarmati and A. H. Kapadi J. Amer. Chem. Soc. 1974 96 7815; ibid. 1976 98 2617. Biological Chemistry-Part (iv)Alkaloids 41 1 Ac (64) R'=O R2=R3=H Talatisamine (63) R =H (65) R1 =0,R2=OZCPh R3=H (72) R=Ac (66) R'=<O] R2=OH R3=H (67) R'=<"-J R~R~=O 0 0 rMe ____--/OMe #I I, M&z] \. .'OR CH20Me 07, Ac--N (70) R'R~=< R~=O 0 0 ,L* H (71) R'R~=< 7, CH,OMe R~=H~ 0 (68) R =H (73) R1R2=0,R3=H2 (69) R=Ts (74) R' =H R2=OH R3=H2 enabled the question of the structures of neoline chasmanine and homochasmanine to be clarified since these three alkaloids have been chemically correlated with delphi~ine.~~ Wiesner and co-w~rkers~~ had originally assigned structure (76) to neoline.However in a subsequent correlation with chasmanine which had been assigned structure (77) on the basis of a reported correlation with br~wniine,~~ Marion and co-workers assigned structure (78) to ne01ine.~~ New work has now demon-~trated~~*~~*~~ that neoline has structure (76) and that the structures of chasmanine and homochasmanine must now be revised to (79) and (go) respectively. A 13Cn.m.r. study of the bases chasmanine (79) neoline (76) delphisine (75) amongst supports the assignment of the la-groups in structures (75) (76) (79) and (80). The recent X-ray crystallographic studies on delphi~ine~~ and chas- manine" also define the absolute stereochemistries of these alkaloids to be as shown.44 S. W. Pelletier Z. Djarmati and S. LajSiC J. Amer. Chem. SOC.,1974,% 7815. 45 K. Wiesner H. W. Brewer D. L. Simmons D. R. Babin F. Bickelhaupt J. Kallos and T. Bogri Tetrahedron Letters 1960 17. 46 0.E. Edwards L. Fonzes and L. Marion Canad. J. Chem. 1966,44 583. 47 L. Marion J. P. Boca and J. Kallos Tetrahedron Suppl. 1966 8 Pt. 1 p. 101. 48 S. W. Pelletier and S. W. Page in ref. 2 pp. 258-259. 49 S. W. Pelletier and Z. Djarmati J. Amer. Chem. SOC.,1976,98 2626. so S. W. Pelletier W H. De Camp and Z. Djarmati J.C.S. Chem. Cumm. 1976 253. 412 D. G.Buckley TMe OMe Delphisine (75) R' = Ha R2 = R3= Ac (77) R=Me Neoline (76) R'=R 2 =R3=H (78) R=H Chasmanine (79) R' = Me; R2 = R3= H Homochasmanine (80) R' =R2= Me; R3 = H From the above it is clear that the previously reported correlation of chasmanine with br~wniine~~ must be in error.7 Tropane Alkaloids An impressively efficient new route to the synthesis of tropane derivatives has been reported re~ently.~~'~~ This involves as a key stage the promotion of C-C bond formation by means of transition-metal carbonyl~.'~ The most useful synthetic route to arise from this work involves the reaction of aaa'a'-tetrabromoacetone and N-methoxycarbonylpyrrole with di-iron enneacarbonyl which gives finally the mixture of adducts (81)and (82) which were readily separated (Scheme 10). Under MeO,C Br2CHCOCHBr2 R3 H (81) R' =H. R2 =R3=Br (82) R'=R 3 =Br; R2=H Scheme 10 appropriate conditions (H2-Pd/C-EtOH) the double bond could be hydrogenated and the bromine atoms removed simultaneously from the mixed adducts (81) and (82) to give the ketone (83).Reduction of (83) with an excess of di-isobutylaluminium hydride at -78 "C then gave a separable mixture of tropine (84) and pseudotropine (85). It is noteworthy that this last stage unlike most chemical methods of reduction affords predominantly the desired a,-alcohol. A potentially more important use of the adducts (81) and (82) consists of the removal of the bromine atoms without hydrogenation of the double bond by means s1 R. Noyori S. Makino Y. Baba and Y. Hagakawa Tetrahedron Letters 1974 1049. 52 R. Noyori Y. Baba and Y. Hayakawa J. Amer. Chem. SOC.,1974,% 3336. s3 J.E. Saxton in ref. 1 pp. 74-75. Biological Chemistry -Part (iv) Alkaloids of Zn-Cu in methanol to give the unsaturated ketone (86). Reduction of (86) with di-isobutylaluminium hydride then affords the alcohols (87) and (88)(in proportion 93 :7) the former of which is a vital intermediate in the synthesis of alkaloids such as scopine (89) and teloidine (90).52 MeO,C MeO,C N N (84) R' = OH; R2=H (85) R' = H; R2= OH Me\ HOH 0 A H R' OH OH (87) R' = OH; R2 =H (88) R' = H R~=OH (89) 8 Miscellaneous Alkaloids Early investigations of the biosynthesis of the unusual heterocyclic acid (91) were without significant issue.54 An attractive mechanism for ring-closure of methionine (92) was envisaged," but experimental proof was lacking.43 MeS-CH2-CH2 I HN-Lco,H H2N-$H-F02H (91) (92) Methionine A specific incorporation of [1-I4C 4-3H]methionine [as (92)] into azetidine-2- carboxylic acid (91) without change in isotope ratio showed that the oxidation level at C-4 was unaffected in the biotransformation of (92) into (91) thus excluding as intermediates aspartic+ -semialdehyde (93) and aspartic acid (94).56 Conflicting evidence on the relative levels of incorporation of homoserine (95) and methionine has been ~btained,~~*~~ although the differences are quite small. However when a relatively large amount of inactive homoserine was fed together with labelled methionine incorporation of the latter decrea~ed.~~ It seems likely therefore that homoserine (95) is a biosynthetic intermediate.More significantly [l-14C 2-3H]methionine [as (92)] was incoporated with almost complete tritium loss and so methionine and S-adenosylmethionine cannot be the ultimate precursors of (9 1)? Further 2,4-diaminobutyric acid (96) has been found 54 R. B. Herbert in ref. 1,pp. 50-51. 55 E.Leete J. Amer. Chem. SOC. 1964,86,3162. 56 E.Leete G. E. Davis C. R. Hutchinson,K. W. Woo and M. R. Chedekel,Phytochemistry 1974,13,427. 57 M.-L. Sung and L. Fowden Phytochemistry 1971.10 1523. 414 D.G.Buckley R-CH2 I H2N-CH-CO2H (93) R=CHO (94) R=COZH (95) R=CH20H (96) R = CH2NH2 to be a better precursor for (91) than methionine.” The loss of tritium originally present at C-2 of methionine can be accounted for if 4-amino-2-ketobutyric acid is an intermediate derivable from (96).Ring-closure of the amino-ketone would give azetine-2-carboxylic acid (97) which in turn would generate azetidine-2-carboxylic acid (91) on reducti~n.~~’~~ N-I_LCO,H (97) The structures of the azaphenalene alkaloids of Poranthera corymbosa poran-therine (98) porantheridine poranthericine (99) and 0-acetylporanthericine (1 00) (99) R=H (100) R=Ac are now firmly established and the structure of a new base porantheriline (101) has been determined. 58*59 (ax) AcO*-w A remarkably successful total synthesis of the tetracyclic alkaloid (It)-porantherine (98) by Corey and Balanson6’ (Scheme 11) was planned by means of computer-assisted retrosynthetic analysis.The 6-amino-undeca-2,lO-dionederiva-tive (102),efficiently prepared in four stages from 5-chloropentan-2-one ethylene acetal was cyclized to the A2-piperideine (103) (ring A). Ring B was formed by acid-catalyzed addition to the enamine. Removal of the N-methyl group and J8 S. R. Johns J. A. Lamberton A. A. Siournis and J. Suares Austral. J. Chem. 1975 27 2025. 59 M. F. Grundon in ref. 2 pp. 100-101. 6o E. J. Corey and R. D. Balanson J. Amer. Chem. SOC.,1974,96,65 16. Biological Chemistry -Part (iv) Alkaloids 3 2 Me B t-~ v-vii o> Me B iii iv Me B 0 Reagents:i 10% aq. HCI; ii TsOH-MeCO,C(Me) CH,-PhH reflux; iii Cr0,-py; iv Os0,-HIO,; TsOH-(CH20H),; vi 110 "C-OH-EtOH; vii 10% aq. HCI; vin 110 "C-TsOH-PhMe; ix NaBH,; x SOC1,-py.Scheme 11 oxidation of the terminal double bond resulted in cyclization of an amino-aldehyde to give ring C cf. (104). Intramolecular addition to the enamine function then furnished the tetracyclic ketone (105) which was converted readily into (*)-porantherine (98).

ISSN:0069-3030    

DOI:10.1039/OC9767300397

出版商:RSC    

年代:1976

数据来源: RSC

摘要:

14 Biological Chemistry Part (v) Neurochemistry Receptors for Drugs and Neurotransmitters ~~ By J. F. COLLINS Department of Chemistry City of London Polytechnic London EC3N 2EY 1 Introduction In an interview' published in 1974 Sir Robert Robinson questioned about the future direction of organic chemistry replied that he thought that among areas which would develop rapidly would be the field associated with the transmission of nerve impulses. This review aims to outline some of the advances made in this field during the past five years. In particular emphasis will be placed on how drugs and neurotransmitters interact with their post-synaptic receptors. It has long been thought that neurotransmitters exert their effects on target tissues by combining with specific receptor sites and in recent years it has been possible to demonstrate this resulting from the development receptor-specific ligands radiolabelled at high specific activities.However a number of basic criteria must be fulfilled* before it can be suggested that binding of a radiolabelled ligand in intact tissue or to a subcellular fraction represents selective binding to the receptor in question. These are (i) Specificity concentrations of drugs which are pharmacologically effective at a particular receptor should displace the saturable component of binding while pharmacologically effective concentrations of drugs acting at different receptors should be ineffective. Known structure-activity relationships must also be complied with and the receptor must have a high affinity for the radiolabelled ligand.(ii) Saturability a component of the binding site must saturate with increasing concentrations of the radiolabelled ligand since the number of receptors is finite. (iii) Comparability the apparent binding affinity of the radiolabelled ligand should be close to that necessary for it to act as an antagonist/agonist of the physiological response. (iv) Localization the saturable component of the specific receptor binding should be localized only to those tissues which are known to show the appropriate pharmacological response. A number of receptors have been characterized resulting in some very significant biochemical advances. 1 R. Robinson Chem. in Britain 1974 57. 2 N.M.Birdsall and E.C. Hulme J. Neurochem. 1976,27,7; S. H. Snyder Biochem Pharmacol. 1975,24 1371. 416 Biological Chemistry -Part (v ) Neurochemistry 2 The Opiate Receptor For many years it has been known that the analgesic potency of opiates is highly stereospecific with virtually all the pharmacological activity residing in those isomers with a configuration analogous to that of (-)-morphine. The (+)-isomers have been shown to be pharmacologically inert having neither agonist nor antagonist proper- ties. Goldstein3 suggested that similarly to the opiate analgesics the pharmacologi- cally relevant opiate receptor binding should be stereospecific. It was assumed that there are three kinds of interaction between an opiate and membranes containing opiate receptors (i) a non-saturable interaction associated with the physical solution of the lipophilic opiate molecules in the lipidic membranes; (ii) a non-specific saturable binding associated with ionic interaction between the protonated nitrogen of the opiate and anionic groups on the membrane; and (iii) the stereospecific interaction between the (-)-opiate and the receptor.If the membrane containing the receptors is incubated with a radiolabelled ligand (expt 1) then the bound radioactivity is a measure of the sum of all three types of binding. If initially the membrane is incubated with an excess of unlabelled opiate of the inactive configuration and the radiolabelled ligand added (expt 2) and the bound radioactivity measured then the difference 1-2 measures the non-specific saturable binding as the unlabelled opiate excludes radiolabelled ligand from the non-specific saturable sites.In the third experiment the membrane is initially incubated with a non-radioactive opiate of the (-)-configuration and the radiolabel- led ligand is then added and the bound radioactivity measured (expt 3). The radiolabelled ligand is thus excluded from both the non-specific and stereospecific sites and consequently the difference 2-3 in the bound radioactivity will be a measure of the stereospecific binding. Using this conceptualization it has been ~hown,~ using [3H]naloxone (an opiate antagonist) of high specific activity that stereospecific opiate receptor binding could be observed in homogenates of mouse brain.Levorphanol a potent opiate agonist was shown to reduce the total binding of [3H]naloxone by 70°/0 whereas at similar concentrations its analgesically inactive( +)-enantiomer dextrorphan was without effect on the binding. More re~ently,~ using opiate ligands of higher specific activity >90% of the binding has been shown to be stereospecific. This stereospecific binding affinity has been shown to parallel the pharmacological potency of a wide variety of both opiate agonists and antagonists.6 Similar results have been obtained by Terenius’ and Simon,’ using a number of different radiolabelled antagonists and agonists. Within the brain it has been shown that stereospecific opiate receptor binding is localized to the synaptic membranes.’ Investigations have also been carried out into the regional distribution of the specific opiate receptor within the brain and very considerable variations have been detected in both monkey and human brain with the anterior amygdala containing the highest concentration of binding sites.’ No correlation of opiate A.Goldstein L. Lowney and B. K. Pal Proc. Nut. Acad. Sci. U.S.A. 1971 68 1742. C. B. Pert and S. H. Snyder Science 1973,179 1011. S. H. Snyder ‘Handbook of Psychopharmacology’ Plenum New York 1976 Vol. 5 p. 335. R. S. Wilson M.E. Rogers and S. H. Snyder J. Medicin. Chem. 1975 18 240; C. B. Pert and S. H. Snyder Proc. Nat. Acad. Sci. U.S.A.,1973,70 2243. L. Terenius Acra Pharmacol. Toxicol. 1973,33 377; 1974 34 88. E. J. Simon J. M. Hiller and I. Edelman Proc.Nar. Acad. Sci. U.S.A.,1973 70 1947. 9 M. J. Kuhar C. B. Pert and S. H. Snyder Nature 1973,245,447. 418 J. F. Collins binding with the distribution of acetylcholine catecholamines y -aminobutyric acid or serotonin could be detected while lesions of well-known nerve tracts specific for acetylcholine noradrenaline and serotonin produced no change in specific opiate binding in the affected areas.9 Sodium ions have been shown to be important in mediating the specific binding." Sodium ions considerably enhance the binding of antagonists such as naloxone whereas the binding of agonists such as morphine is markedly decreased Mixed agonist-antagonist drugs e.g. pentazocine are affected by sodium ions in an intermediate fashion. The increase in antagonist binding found on the addition of sodium ions has been shown to be caused not by a change in the receptor affinity but by an increase in the number of receptor sites available.Iodoacetamide," a protein-modifying reagent has been shown to markedly reduce the receptor binding of a series of agonists but does not affect the binding of antagonists. Proteolytic enzymes1* have also been shown to inhibit agonist binding more than antagonist binding whereas bivalent cations especially manganese ions have been shown to have the opposite effect.13 It has therefore been suggested that the opiate receptor can assume two different conformation^,'^ one favouring antagonists the other favouring agonists. The two conformations can be allosterically transformed by sodium ions and it would appear that the agonist conformation is the more labile.Snyder15 has proposed a model of the opiate receptor explaining the structure-activity relationship of opiates and suggesting molecular mechanisms for the interconversion of the receptor between the agonist binding state and the antagonist binding state. The agonist conformation at some sites of action has been shown to inhibit a linked adenylate cyclase enzyme.16 As the opiate analgesics have been shown to interact with stereospecific receptors in certain discrete regions of brain and as it has been shown that none of the established or putative neurotransmitter substances appeared to interact with the opiate receptors it was suggested that the mode of action of the opiates might well involve an unknown mechanism in brain.As many neurotransmitters are derived from amino-acids it was suggested that the endogeneous ligand of the opiate receptor might be a peptide. This theory was substantiated in 1975." In subsequent work it was found that the substance which had been named 'enkephalin' could be extracted from pig brain'' and it was found to have a molecular weight of approxi- mately 1000. Biological activity was found to be very rapidly destroyed if the substance was exposed to proteolytic enzymes and a similar substance was shown to be present in extracts of cat rabbit guinea-pig and cow brains. An important 10 C. B. Pert and S. H. Snyder Mol. Pharmacol. 1974 10 868. C. B. Pert G. W. Pasternak and S. H. Snyder Science 1973,182 1359.11 H. A. Wilson G. W. Pasternak and S. H. Snyder Nature 1975,253,448. ** G. W. Pasternak and S. Snyder Mol. Pharmacol. 1975,11,478. l3 G. W. Pasternak and S. H. Snyder Mol. Pharmacol. 1975 11,735. 14 C. B. Pert and S. H. Snyder Mol. Pharmacol. 1974 10 868; Neurosci. Res. Prog. Bull. 1975 73. 15 A. P. Feinberg I. Creese and S. H. Snyder Proc. Nar. Acad. Sci. U.S.A.,1976,73 4215. 16 S. K. Sharma M. Birenberg and W. A. Klee Proc. Nar. Acad. Sci. U.S.A. 1975,72 590; 0.J. Collier and A. C. Roy Nature 1974,248 24. 17 J. Hughes BrainRes. 1975,88,295;L. Terenius and A. Wahlstrom Acta Physiol. Scand. 1975,94,74. 18 J. Hughes T.W.Smith H. W. Kosterlitz L. A. Fothergill B. A. Morgan and H. R.Morris Nafure,1975 258 577. Biological Chemistry -Part (u)Neurochemistry 419 similarity between morphine and enkephalin was that the effects of both substances in blocking electrically evoked contractions in either the guinea-pig ileum or mouse vas deferens could be reversed by low concentrations of specific morphine antagon- ists such as naloxone.Enkephalin” also displaced radioactively labelled opiates in the binding assay and it was found that the ability of enkephalin to displace the radiolabelled ligands was decreased by the addition of sodium ions suggesting that the compound is an agonist at opiate receptors. [3H]Met-enkephalin has been shown to bind with high affinity to the opiate receptor in the absence of sodium ions. It has also been demonstrated that displacement by morphine or Met-enkephalin of a radiolabelled opiate agonist followed different kinetics from their displacement of labelled antagonists.20 Met-enkephalin has been shown to be much weaker in competing for binding sites for radiolabelled naloxone than in competing for its own binding sites and morphine was much less effective in competing for [3H]enkephalin binding than in the displacement of 3H-opiates.21As a consequence it has been suggested either that there are different binding sites for enkephalins and opiates or that the opiate receptor can exist in multiple receptor conformations.l9 Hughes et al. have purified enkephalin and sequenced the peptide using both the dansyl-Edman technique and mass spectrometric methods. Porcine enkephalin has been found to consist of a mixture of two pentapeptides H-Tyr-Gly-Gly-Phe-Met- OH (Met-enkephalin) and H-Tyr-Gly-Gly-Phe-Leu-OH (Leu-enkephalin) in a ratio of about 3 1.Both compounds have been synthesized,22 and the synthetic peptides have been shown to mimic the actions of naturally occurring enkephalin in the biological test systems. On theoretical grounds G~ldstein~~ has designed and synthesized a heptapeptide H-Try-Gly-Gly-Gly-Lys-Met-Gly-OH, which posses- sed low opiate activity. A large number of synthetic peptides have now been evaluated for their opiate activity and some important structure-activity relationships have emerged (i) when the free amino-group of the tyro~ine~~ residue is blocked25 or removed the opiate activity completely disappears; (ii) phenylalanine cannot replace tyro~ine,~~ hence the phenolic group is also necessary for activity; (iii) a tetrapeptide H-Tyr-Gly-Gly- Phe-OH appears to be the smallest peptide which will interact with the opiate receptor;25 (iv) amidation of the C-terminal of Met-enkephalin considerably increases the and the duration of action; (v) potency is lost when tyrosine is substituted for 4-Phe;24 (vi) both Met-enkephalin and Leu-enkephalin have been found to be very susceptible to hydrolysis by non-specific proteolytic enzymes in 19 R.Simontov and S. H. Snyder in ‘Opiates and Endogeneous Opiate Peptides’ ed. H. W. Kosterlitz North Holland Amsterdam 1976 p. 41; R. Simontov and S. H. Snyder J. Neurochem. 1977,28 13. 20 J. A. H. Lord A. A. Waterfield J. Hughes and H.W. Kosterlitz in ‘Opiates and Endogeneous Opiate Peptides’ ed. H. W. Kosterlitz North Holland Amsterdam 1976 p. 275. 21 N. Birdsall in ‘Opiates and Endogeneous Opiate Peptides’ ed. H. W. Kosterlitz North Holland Amsterdam 1976 p. 19. 22 J. D. Bower K. P. Guest and B. A. Morgan J.C.S. PerkinI 1976,2488; W. Voelter E. Pietrzik and H. Kalbacher Tetrahedron Letters 1976 2 119. 23 A. Goldstein J. S. Goldstein and B. M. Cox Life Sci. 1976 17 1643. 24 N. J. M. Birdsall A. F. Bradbury A. S. V. Burgen E. C. Hulme D. G. Smyth and C. R. Snell Brit. J. Pharmacol. 1976,58 460P. 25 N. Ling and R. Guillemin Prm.Nat. Acad. Sci. U.S.A.,1976 73 3308. 420 J. F. Collins brain and as a consequence analgesia induced by enkephalin is of a very short duration and high doses of enkephalin are required.26 Deactivation has been shown to proceed via cleavage of the Try-Gly amide bond.27 However when 2-Gly is replaced2’ by 2-D-Ala in Met-enkephalin the product after amidation binds almost as tightly as Met-enkephalin to opiate recep- tors.As the compound is not susceptible to enzymic degradation low doses cause long-lasting morphine-like analgesia when microinjected into mouse brain. Similarly when 2-Gly is replaced by 2-D-Ala and 5-Leu by 5-D-LeU in Leu- enkephalin a potent opiate peptide is obtained.28 Other active pentapeptides have been prepared by replacement of 2-Gly by D-proline and D-sarcosine. As the opiate receptor is highly stereospecific for morphine derivatives but clearly not so for enkephalin derivatives a number of investigators have attempted to determine the conformation of enkephalin in solution in an attempt to relate this to the structure of morphine-derived anLigesics.On theoretical grounds it has been postulated that in Met-enke~halin,~~ a P-bend exists involving the two glycine residues in positions 2 and 3 with a hydrogen bond between the carbonyl group of the tyrosine and the amino-group of the phenylalanine. Attention has been drawn to the close similarity of this conformation of enkephalin to the structure of oripavine a potent opiate agonist. The conformation of enkephalin in solution has been investigated by several groups using n.m.r. spectroscopy. One series of experiments using the Karplus- Bystrov curves suggests that for Met-enkephalin in DMSO the methionine amino- proton is involved in a hydrogen bond most probably within a Gly-Gly-Phe-Met type 10 t~x-n.~”~~ Leu-enkephalin has been found to have basically the same conformation in DMS0.31 However other have interpreted relaxation times to suggest that there are no intramolecular hydrogen bonds and that the tyrosine side-chain of Met-enkephalin exhibits restricted motion with respect to the main peptide backbone of the molecule unlike the phenylalanyl and methionyl side-chains which undergo intramolecular reorientation with relatively high fre- quency.It is important to note however that whatever the conformation of enkephalin in solution there may be no correlation between this and the conformation adopted on the receptor.It has also become apparent that there are other large peptides present in brain which are also potent opiate agonists and the generic title ‘endorphin’ has been proposed for them. A number of endorphins have been isolated and most appear to 26 J. B. Chang B. W. T. Fong A. Pert and A. C. Pert LifeSci. 1976,18,1473; J. D. Beluzzi N. Grant V. Garsky D. Sarantakis C. D. Wise and D. Sarantakis Nature 1976 260 604. 27 J. M. Hambrook B. A. Morgan M. J. Rance and C. F. C. Smith Nature 1976,262,782. 28 C.P. Pert A. Pert J. K. Chang and B. T. Fong Science 1976,194,330; M. G. Baxter D. Goff A. A. Miller and I. A. Saunders Brit. J. Pharmacol 1977,59,455P. 29 A. F. Bradbury D. G. Smyth and C. R. Snell Nature 1976,260 165. 30 B. P. Roques C. Garbay-Jaurguiberry R.Oberlin M. Antenius and A. K. Lala Nature 1976,262,778. 31 C. R. Jones W. A. Gibbons and V. Garsky Nature 1976,262,779. 32 H. E. Bleich J. D. Cutnell A. R. Day R. J. Freer J. A. Glasel and J. F. McKelvy Proc. Nat. Acad. Sci. U.S.A.,1976 73 2589. Biological Chemistry -Part (v ) Neurochemistry 42 1 be fragments of p-lipotropin a pituitary ~eptide~~ containing 9 1 amino-acids (see Figure). These fragments are (i) C-fragment of @ -1ipotropin (or p-endorphin) residues 6 1-9 1of p -1ipotropin; (ii) a-endorphin corresponding to residues 61- 76; and (iii) y-endorphin corresponding to residues 61-87. All three exhibit potent opiate agonist activity though -endorphin is much the most active;33 in the opiate binding assay employing rat brain @ -endorphin was found to be 30-fold more potent in displacing [3H]naloxone than Met-enke~halin.~~ @ -Endorphin has been syn- the~ized~~ and the product has been shown to possess activity comparable with that of naturally occurring /3 -endorphin.1 5 10 16 Try -Gly-Gly -Phe-Met -Thr-Ser-Glu-Lys-Ser-Gln-Thr-Pro- Leu-Val-Thr-20 27 31 Leu-Phe-Lys-Asn-Ala-lle-Val-Lys-Asn-Ala-His-Lys-Lys-Gly-Gln-OH Residues 1-5 of p-endorphin Met-enkephalin Residues 1-16 of p -endorphin a-endorphin Residues 1-27 of p -endorphin y-endorphin Figure C-Fragment of p-1ipotropin or @-endorphin The amino-acid sequence of Met-enkephalin corresponds to residues 6 1-65 of p-lipotropin and a-,p- and y-endorphins share this sequence at the N-terminal end. p -Lipotropin however is itself devoid of opiate activity.It has been suggested that one naturally occurring pituitary endorphin is @ -endorphin while the smaller endorphins including Met-enkephalin are formed from this ~eptide.~~ No candidate precursor for Leu-enkephalin has yet been found. It has been that removal of amino-acid residues 30 and 3 1(Gly-Gln) from @-endorphin has little effect on the binding properties but further removal of residues 28 and 29 (Lys-Lys) (leaving y-endorphin) reduces the binding affinity by a factor of 20. It has been suggested that interaction of C-terminal residues including lysines 28 and 29 with the receptor may make an important contribution to the binding of P-endorphin both augmenting the affinity and modifying the binding properties of the N-terminal pentapeptide sequence.Birdsall and co-workers have shown that the tridecapeptide composed of residues 19-3 1 inhibits [3H]naloxone binding despite the absence of the Met-enkephalin sequence thus suggesting that there is a binding site for the C-terminu~.~~ The enkephalins have been suggested to be endogeneous neurotransmitters l9 but this role has been questioned33 and the longer endorphins have been suggested as more plausible candidates. However the existence of enkephalin nerve terminals has been demonstrated (using immumohistochemistry) and their distribution corre- A. Goidstein Science 1976,193 1081; A. F. Bradbury D. G. Smyth C. R. Snel1,N. J. Birdsall andE. C. Hulme Nature 1976 260 793; B. M. Cox A. Goldstein and C. H.Lio Proc. Nut. Acad. Sci. U.S.A. 1976,73 1821; R. Guillemin N. Ling and R. Burgus Compt. rend. 1976,282 C,783; N. J. Birdsall A. F. Bradbury A. S. V. Burgen E. C. Huime D. G. Smyth and C. R. Snell Brit J. Pharmacof. 1976,58 460P. A. A. Waterfield J. Hughes and H. W. Kosterlitz Nature 1976,260,624; L. F. Tseng H. H. Loh and C. H. Li Proc. Nut. Acad. Sci. U.S.A.,1976.73 4187. C. H. Li S. Lemaire D. Yamashiro and B. A. Doneen Biochem. Biophys. Res. Comm. 1976 71 19. 422 J. F. Collins lates well with the opiate receptors as determined using a~toradiography.~~ P -Endorphin has been found to occur in mammalian brain but the concentrations found are very much lower than those of the enkephalin~,~~ and it has been suggested that whereas the pituitary contains high levels of the larger peptides and has low enkephalin levels the brain contains high levels of enkephalins but low levels of larger endorphins.l9 Both the enkephalins and P -endorphin have been shown to produce tolerance and eventually dependence when given intra~erebrally.~~ However P -endorphin has been shown to induce much more profound analgesis than the enkephalins when given intraventricularly but this may be due to the rapid inactivation of enkepha- 1i1-1.~~ Cross-tolerance has also been observed both between enkephalin and mor- phine and P -endorphin and Snyder39 has shown that increased concen- trations of enkephalin can be detected in morphine-dependent rats. This increase may be due to pre-synaptic synthesis of enkephalin continuing in the absence of release.Endorphins other than those derived from P -endorphin have been dete~ted.~~.~’ These are different in that (i) their biological activity is destroyed by trypsin which is not the case for those derived from p-lipotropin; (ii) even in impure preparations they are considerably more potent than the P-lipotropin endorphins; (iii) the biological activity of these endorphins is insensitive to cyanogen bromide treatment indicating the absence of an essential methionine residue. Wahl~trom~’ has also isolated a peptide with opiate activity from human cerebrospinal fluid which is chemically different from all known fragments of P -1ipotropin. A blood-extracted substance of unknown structure but of low molecular weight named an~dynin,~~ both competes for opiate receptor binding and is a potent analgesic when injected directly into cat brain.Anodynin has been shown to be absent from the blood of hypophysectomized rats and consequently is thought to derive from the pituitary. 3 The Cholinergic Receptor Acetylcholine an excitatory neurotransmitter has been shown to act at two different types of post-synaptic receptor namely nicotinic and muscarinic receptor^.^^ Although no successful attempts have yet been made to characterize the nicotinic receptor in mammalian brain tissue the nicotinic receptors present at the neuromus- cular junction have been successfully identified44 using elapid toxins. In particular a-neurotoxins and polypeptide toxins such as a-bungarotoxin isolated from the venom of Bungarus multicinctus have been extensively used in the receptor isolation studies from various tissues e.g.the electric organs of the Torpedo and electric eel 36 R. Elde T. Kokfelt 0.Johansson and L. Terenius Neuroscience 1976 1,349. 37 A. Lampert M. Nirenberg and W. A. Klee Proc. Nut. Acad. Sci. U.S.A.,1976,73,3165; J. M. Van Ree D. De Wied A. F. Bradbury E. C. Hulme D. G. Smyth and C. R. Snell Nature 1976,264 792. 38 H. H. Loh L. F. Tseng E. Wei and C. H. Li Proc. Nut. Acad. Sci. U.S.A.1976 73 2895. 39 R. Simantov and S. H. Snyder Nature 1976,262 505. 40 B. M. Cox S. Gentleman T. P. Su and A. Goldstein Bruin Res. 1976 115 285. 41 A. Wahlstrom in ‘Opiates and Endogeneous Opiate Peptides’ ed. H. W. Kosterlitz North Holland Amsterdam 1976 p.49. 42 C. B. Pert A. Pert and J. H. Tallman Proc. Nut. Acud. Sci. U.S.A.1976,73 2226. 43 R. B. Barlow ‘Introduction to Chemical Pharmacology’ Methuen London 1964. 44 J. P. Changeux in ‘Proceedings of the Sixth International Congress of Pharmacology’ ed. F. Klinge Pergamon Press Oxford 1976 p. 165. Biological Chemistry -Part (u)Neurochemistry 423 and striated muscle. The successful use of these toxins as essential tools in the identification localization and isolation of the nicotinic acetylcholine receptor is due to two factors (i) the action of the toxin is very specific and (ii) the snake toxin associates in a very tight but reversible manner with the receptor so that the rate of dissociation is very low. The polypeptide toxin can be labelled in a number of different ways the most important employing 1251for labelling.The radiolabelling is of course essential for localization studies and also for receptor purification. The solubilized receptor has been purified using affinity chromatography in which the a-neurotoxin was conjugated to an agarose The receptor has been characterized as a and the molecular weight has been estimated at 360 000. It has been solubilized using Triton X-100.46 Extensive reviews have been published on the biochemical characterization of the nicotinic re~eptor.~’ Myas-thenia gravis has been shown to be caused by an autoimmune response to the nicotinic acetylcholine Unlike nicotinic receptors muscarinic receptors have been successfully studied in the mammalian brain.High affinity binding sites have been demonstrated to exit using a large number of radiolabelled muscarinic antagonists. These include the potent antagonist 3-quinuclidinyl benzilate (QNB),49 atr~pine,~’ benzetimide,” and propylbenzilylcholine (PrBCh).” The specific binding of C3H]QNB was found to be almost completely blocked by excess cold QNB indicating saturable binding. The specific binding defined as the total binding minus the binding in the presence of 0.01 pmol I-’ unlabelled QNB is saturable with respect to [3H]QNB and tissue concentration and is dependent on time temperature and pH.49 Other muscarinic antagonists and agonists were shown to displace specific [3H]QNB binding,49 but nicotinic antagonists showed no affinity for the QNB binding sites.For a given 3H-antagonist the maximum degree of displacement of binding is the same for all competing muscarinic antagonists or agonists. The level of binding in synaptosomal fractions derived from rat brain has been shown to be similar for all the 3H-antagonists so far studied and to be in the range 1.6-2.2 nmol per g pr~tein.’~*~* A close correlation has also been observed between the pharmacological potency of a large number of cholinergic agents and their ability to inhibit radiolabelled antagonist binding in guinea-pig ileum.52 It has been shown that the antagonist binding sites in very diverse tissues such as smooth muscle the parotid gland and brain show very similar affinity constants which do not display variations between different mammalian species.52 The binding 45 J.P. Changeux M. Kasai and C. Y. Lee Proc. Nat. Acad. Sci. U.S.A.,1970 67 1241; R. Miledi P. Molinoff and L. T. Potter Nature 1971,229,554; R. P. Klett B. W. Fulpius D. Cooper and E. Reich in ‘Synaptic Transmission and Neuronal Interaction’ Raven Press New York 1974 pp. 179. 46 J. Lindstrom and J. Patrick in ‘Synaptic Transmission and Neuronal Interaction’ Raven Press New York 1974 p. 191. 47 M. A. Raftery. J. Deutch K. Reed R. Vandlen and T. Lee in ‘Proceedings of the Sixth International Congress of Pharmacology’ ed. F. Klinge Pergamon Press Oxford 1976 p. 87; Z. Vogel and M. P. Daniels ibid. p. 59; F. A. Barnard and J. 0. Dolly ibid. p. 77; C. Y. Lee in ‘Neuropoisons; their Pathophysiological Actions’ ed.L. L. Simpson Plenum New York 1971 Vol. 1 p. 21. 48 A. Aharonov R. Tarrab-Hazdai 0.Abramsky and S. Fuchs Proc. Nut. Acad. Sci. U.S.A. 1975 72 1456. 49 H. I. Yamamura and S. H. Snyder Proc. Nut. Acad. Sci. U.S.A.,1974,71 1725. J. T. Farrow and R. D. O’Brien Mol. Pharmacol. 1973,9 33; A. J. Beld and E. J. Ariens European J. Phannacol. 1974,30 360. 51 N. J. Birdsall A. S. Burgen C. R. Hiley and E. C. Hulme J. Suprumol. Structure 1976 4 367. s2 N. J. Birdsall and E. C. Hulme J. Neurochem. 1976 27 7. 424 J. F. Collins curves observed by a number of the radiolabelled antagonists are exactly of the form expected when the law of mass action is applied to the interaction of a ligand with a single uniform set of binding sites. The regional distribution of muscarinic antagonist sites in brain has been examineds3 using [3H]QNB and the caudate nucleus and the cerebral cortex have been found to contain high concentrations of muscarinic receptor sites.In contrast to the simple antagonist binding studies have revealed that muscarinic agonist binding is complex and cannot be described by a single affinity constant,52 and it has been suggested that a heterogeneous population of agonist binding sites exists. It has been postulated that the heterogeneity of the agonist binding sites can be explained on the basis that (i) two classes of agonist binding site exist one having a high affinity constant and the other a low affinity constant for agonist binding; (ii) the antagonist binding sites linked to the two types of agonist site have identical affinities for a given antagonist; and (iii) binding of agonists and antagonists is competitive and mutually exclusive.Similar suggestions have been made for a number of other receptor systems including the opiate receptor and the glycine re~eptor.’~ The muscarinic receptor has not yet been solubilized using detergents as binding activity is de~troyed.’~ However solubilization using digitonin has been reported.” 4 Catecholamine Receptors Although specific P -adrenoceptor binding in tissues has proved difficult to observe several groups55 have now managed to demonstrate its existence. It was necessary to use potent high specific activity P-adrenoceptor antagonists as ligands. Typical antagonists used were D~-[~H]proprananol (-)-[3H]alprenolol and [‘251]hydroxybenzylpindolol.All have very high binding constants ca.lo9 1mol-’. Initially avian or amphibian red blood cell membranes were used as the source tissue for binding studies but more recently 0-adrenergic receptors have been charac- terized in rat brain using (-)-[3H]alprenolol.56 The binding was found to be specific very rapid saturable and reversible. It was found that the (-)-isomers of the unlabelled antagonists propranolol and isoprenaline were highly potent in compet- ing for the binding sites in brain the (+)-inactive-isomers being about two orders of magnitude less potent. Binding could also be inhibited by other P-adrenoceptor antagonists and by catecholamines such as (-)-adrenaline and (-)-noradrenalhe.At high concentrations phentolamine an a -adrenoceptor antagonist displaced (-)-[’H]alprenolol but this is thought to be similar to the non-specific inhibitory effect of high concentrations of phentolamine on 0-adrenergic physiological responses. The highest number of [3H]alprenolol binding sites was found to be in the hippocampus and limbic forebrain areas of the brain (0.26 and 0.28 pmol per mg protein respectively) but there appeared to be no correlation between levels of noradrenaline and the number of P-adrenergic receptors in various regions of the 53 S. Yamamura M. Kuhar and S. Snyder Bruin Res. 1974,66 541; 1974,80 170. 54 A. Young and S. H. Snyder Roc.Nut. Acad. Sci. U.S.A.,1973,70,2832. 55 G.D.Aurbach S. A. Fedak C. J. Woodard J.S. Palmer D. Hauser and F. Troxler Science 1974,186 1223;R.W. Alexander L. T. Williams and R. J. Lefkowitz,Proc. Nut. Acud. Sci. U.S.A.,1975,72,1564; A. Levitzki D.Atlas and M. J. Steer ibid. 1974 71 2773 4246. 56 R. W. Alexander J. N. Davis and R. J. Lefkowitz Nature 1975,258 437. Biological Chemistry -Part (v)Neurochemistry 425 brain. Similar results have been obtained using DL-[3H]propranolol in chick brain.57 Stereospecific binding of [3H]dopamine to membranes from the corpus striatum of rat brains has been dem~nstrated.~~ The stereospecific component of the binding was defined as the amount of [3H]dopamine bound in the presence of (-)-butaclamol (an inactive compound) minus that bound in the presence of (+)-butaclamol (a potent neuroleptic compound).A number of antipsychotic drugs the most potent being spiroperidol inhibited the stereospecific binding. The inhibitory potencies correlated well with clinical doses used in the treatment of schizophrenia. Snyder” and co-workers have also shown using as a definition of specific dopamine binding the total minus the binding in the presence of a large excess of non-radioactively labelled dopamine that the binding is saturable and that apomorphine is about twice as potent as dopamine in competing for binding sites. [3H]Apomorphine has recently been shown to be a better radioligand than [3H]dopamine or [3H]haloperidol.60 Specific binding of the a -noradrenergic agonist [3H]clonidine and the antagonist [3H]-2-(2’6’-dimethoxyphenoxyethylamino)methylbenzodioxan(WB 4101) has been shown to occur in rat brain.61 Both bind with high affinity and selectivity and the binding was found to be saturable.In exchange experiments a-agonists have much higher affinities for the [3H]clonidine sites than for 3H-WB 4101 sites whereas the reverse has been shown to hold for a -antagonists. Mixed agonist-antagonist drugs have been shown to have a similar affinity for binding for the two radiolabelled ligands. It has been suggested that [3H]clonidine and [3H]WB 4101 respectively label separate agonist and antagonist states of the receptor and that the receptor exists in two conformations with selective affinities for agonists and antagonists.61 5 Amino-acid Receptors A number of amino-acids have been suggested to act as neurotransmitters.Amongst these are L-glutamate glycine and y -aminobutyric acid (GABA). L-Glutamate has been suggested to be an excitatory neurotransmitter in the mammalian central nervous system62 as it has been found to be a potent excitant when applied microionophoretically to single neurones in certain brain areas. Certain neurones in the CNS also appear to be enriched in gl~tamate.~~ The postsynaptic glutamate receptor has been studied using [3H]kainic Kainic acid a conformationally restricted analogue of L-glutamate is reported to be a powerful excitant which potentiates the excitatory action of glutamate.6s It has S7 S. R. Nahorski Nature 1976 259 488. s8 P. Seeman M. Chau-Wong J. Tedesco and K. Wong Proc. Nut. Acad. Sci. U.S.A. 1975,72,4376.s9 D. R. Burt S. J. Enna I. Creese and S. H. Snyder Proc. Nut. Acad. Sci. U.S.A. 1975,72 4655. 60 P. Seeman T. Lee M. Chau-Wong J. Tedesco and K. Wong Proc. Nut. Acad. Sci. U.S.A. 1976 73 4354. 6l D. A. Greenberg D. C. U. Prichard and S. H. Snyder Life Sci. 1976,19,69. 62 D. R. Curtis and G. A. R. Johnston Ergebn. Physiol. 1974,69,98; K. Krnjevic Physiol. Rev. 1974,54 419. 63 J. A. Harvey C. N. Scholfield L. T. Graham and M. H. Aprison J. Neurochem. 1975,24,445. 64 J. R. Simon J. F. Contrera and M. J. Kuhar J. Neurochem. 1976 26 141. 65 H. Shinozaki and K. Konishi Brian Res. 1970 24 368. 426 J. F. Collins been shown to be very much more potent than L-glutamate in both frog and cat spinal neurones. Synaptosomal uptake of kainic acid has been shown to be minimal and it is not a potent inhibitor of high afFinity L-glutamate uptake.For these reasons it appeared to be a suitable agonist to use in labelling the glutamate receptor. The specific binding of C3H]kainic acid to synaptic membranes was shown to be saturable with a dissociation constant of about 60 nmol l-'.64 Specific C3H]kainic acid binding was obtained by subtracting from the total bound radioactivity the amount not displaced by high concentrations of kainic acid or glutamate. The maximum number of binding sites was found to be about 1pmol per mg protein. Quisqualic acid a structural analogue ofL-glutamate was found to be the most potent displacer of specific r3H]kainic acid binding with a potency of about one-third that of kainic acid itself.L-Glutamate was found to be less potent in binding displacement than either kainic acid or quisqualic acid with a potency of about 1/25 that of kainic acid. Other compounds tested such as L-aspartate a putative excitatory neurotransmit- ter were found to be very much less potent. The specific binding appears to be localized to grey matter. On this evidence it has been suggested that [3H]kainic acid is binding to the glutamate receptor. Glycine66 has been shown to be a major inhibitory neurotransmitter in the mammalian CNS and is thought to be especially important as a transmitter in the spinal cord. Strychnine acts as a potent and selective antagonist for the synaptic actions of gly~ine.~~ The glycine receptor has been studied68 using [3H]strychnine rather than [3H]glycine as use of [3H]strychnine avoids binding of glycine to presynaptic membrane fragments associated with the glycine uptake system and also since pharmacological studies had suggested that strychnine had a much greater affinity for the glycine receptor than glycine itself.Specific strychnine binding to synaptic membrane preparations of spinal cord and brain stem of the rat and monkey has been demonstrated using high specific activity strychnine. The binding has been found to be maximal in the synaptic membrane fraction containing both pre- and post-synaptic membrane fragments. Bound [3H]strychnine has been shown to be displaced by glycine and the specific binding shown to be saturable. In addition [3H]strychnine has been shown to bind to a single population of receptor sites.The number of such binding sites in the rat spinal cord is ca. 39 pmol g-'. The regional distribution of strychnine binding has been examined and has been found to be highest in the spinal cord and the medulla oblongata-pons. Negligible binding was observed in the cerebellum hippocampus and cerebral cortex. The distribution has been found to parallel closely that of endogenous glycine and the high affinity glycine uptake system. In further confirma- tion of the specificity of the strychnine binding the ability of a series of amino-acids to displace bound [3H]strychnine was compared with their ability to mimic the strychnine-antagonized neurophysiological actions of glycine. p -Alanine and glycine have been found to be the most potent amino-acids both neurophysiologi- cally and in the displacement of [3H]strychnine.As in the case of the opiate receptor the agonist-glycine and the antagonist- strychnine appear to bind to distinct but mutually interacting portions of the 66 S. H. Snyder Brit. J. Pharmacol. 1975 53 473. 67 D. R. Curtis A. Duggan and J. Johnston Exp. Brain Res. 1971 12 547. 68 A. B. Young and S. H. Snyder Proc. Nat. Acad. Sci. U.S.A.,1973,70 2832. Biological Chemistry -Part (v)Neurochemistry 427 receptor.69 It has been demonstrated that protein-modifying reagents such as diazonium tetrazole and acetic anhydride while having little affect on the total amount of [3H]strychnine bound to synaptic membranes interfere with the ability of glycine to displace [3H]strychnine but not with the ability of non-radioactive strychnine to displace the binding.Other protein-modifying reagents such as tetranitromethane and dinitrofluorobenzene have been shown to inhibit the total amount of binding of [3H]strychnine but unlabelled glycine and strychnine still displace the remaining bound [3H]strychnine to similar extents. The differential influence of these reagents suggests that glycine displaces strychnine by acting at a site other than the strychnine binding site. The ability of a series of anions to inhibit [3H]strychnine binding in spinal cord synaptic membranes has been e~amined,~’ and it has been suggested that the observed inhibition is closely correlated with the ionic conductance mechanism for the chloride ion in the glycine receptor.Young and Snyder have postulated that glycine binds to its recognition site. This site is composed of regulatory subunits associated with the conductance-modulating site where it is suggested strychnine may bind. A correlation between the clinical efficacy of a series of benz~diazepines~’ and the ability of the compounds to reduce the specific strychnine binding to glycine receptors has given rise to the suggestion that benzodiazepines exert their phar- macological activities by interacting with the glycine receptor. However from in vivo studies with the cat,72 no interaction could be demonstrated between diazepam strychnine and glycine. y-Aminobutyric acid (GABA) has been shown to be a major inhibitory neuro- transmitter in the mammalian CNS.73 Its inhibitory actions are selectively antagonized by the phthaleido-isoquinoline alkaloid (+)-bic~culline,~~ in contrast to the other inhibitory amino-acid neurotransmitter glycine.The inactivity of (-)-bicuculline shows that antagonism to be stereospe~ific.’~ Specific [3H]GABA binding has been examined76 using synaptosomal fractions from rat brain. The binding measured in the absence of sodium ions is selective and saturable. Various amino-acids have been shown to inhibit the [3H]GABA binding and their ability to do this parallels the synaptic inhibitory actions of GABA and does not correlate with their relative affinity for presynaptic high-affinity GABA uptake system. Bicuclline has been shown to inhibit [3H]GABA binding with half maximal effects at 5 pmol 1-’.Thus it would appear that bicuculline has ca. 1/50 the affinity of GABA for the GABA binding sites in synaptic membranes in contrast to strychnine the glycine antagonist which has 10 000 times the affinity of glycine for the glycine receptor. Specific [3H]GABA binding has been shown to be highest in the cerebellum and least in the spinal cord. 69 A. B. Young and S. H. Snyder Mol. Pharmacol. 1974,10,790. 70 A.B.Young and S. H. Snyder Proc. Nut. Acad. Sci. U.S.A.,1974,71,4002. 71 A.B.Young S. R. Zukin and S. H. Snyder Proc. Nut. Acad. Sci. U.S.A. 1974.71 2246. 72 D. R.Curtis C. J. A. Game and D. Lodge Brit. J. Pharmacol. 1976,56,307. 73 D.R.Curtis and G. A. R. Johnston in ‘Handbook of Neurochemistry’ ed.A. Lajtha Plenum Press New York 1970,Vol. 4,p. 115;K. Krnjevic Physiof.Rev. 1974,54,418. 74 D. R. Curtis A. W. Duggan D. Felix and G. A. R. Johnston Brain Res. 1971,33 57. 75 J. F. Collins and R. G. Hill Nature 1974,249 845. 76 S.R.Zukin A. B. Young and S. H. Snyder Proc. Nut. Acad. Sci. U.S.A. 1974,71,4802;S.J. Enna and S. H. Snyder Brain Res. 1975,100,81;S.J. Enna M. J. Kuhar and S. H. Snyder ibid. 1975,93,168. 428 J. F. Collins It has been suggested” that two different binding sites exist on the GABA receptor as the effects of GABA antagonists in the superior cervical ganglion in the rat could be reversed by the application of hypnotic barbiturates whereas pentobar- bitone had no effect on r3H]GABA binding in rat brain synaptosomal preparation^.^^ 77 N.G.Bowery and A.Dray Nature 1976,264,276.

ISSN:0069-3030    

DOI:10.1039/OC9767300416

出版商:RSC    

年代:1976

数据来源: RSC

摘要:

Errata Volume 72B,1975 Page 90 The caption to formula (4)b in Scheme 3 should read “R =C2H5C(CH3)3”. Page 92 The first part of the sentence beginning on the sixth line below scheme 7 should read “if the reaction has no memory then the ratio [(CH3),C-]/3[(CD3),C*]in experiment (i) should equal 3[(CH3),C-]/[(CD,),C*] in experiment (ii) . . . ”. Page 269 line 7 The authors of ref. 117(b) point out that the statement that “. . . (119) reacts with sodium sulphinate and with potassium cyanide to give disulphone (120) (64%) and 2-cyanopyridine (87%) respectively.” is incorrect. Although (119)does react with potassium cyanide as indicated it does not react with sodium sulphinate. It is the 4-chloro- 1-pyridiniopyridinium salt which reacts with sodium benzenesulphinate to give the disulphone (120) in 64% yield. 429

ISSN:0069-3030    

DOI:10.1039/OC9767300429

出版商:RSC    

年代:1976

数据来源: RSC

摘要:

Author Index Abashev G. G. 129 Abbound J.-L. M. 32 209 Abdul-Hai S. M. 89 Abdulnur S. F. 38 Abe H. 379 Abeles R. H. 361 Abenhaim D. 192,313 Abernethy J. C. 369 Abola J. E. 379 Abraham D. J. 379 Abraham D. J. 379 Abraham F. 36 Abramovitch R. A. 260 268 277 Abramsky O. 423 Achini R. 45 Achiwa K. 318 Achmatowin O. 182 Aciaux A. J. 96 Acton N. 97 11 1 Adams B. L. 379 Adams J. H. 268 Adcock W. 203 Adeleke B. B. 82 Adlington M. G. 303 Afridi A. S. 246 Agarwal K. L. 383 392 393 Agawa T. 109 258 Agdeppa D. A. 194 Agopian G. K. 95 Agosta W. C. 158 159 Agranat I. 204 228 Agro A. F. 371 Aguiar A. M. 100 Agurell S. 402 Aharonov A. 423 Aharon-Shalom E. 204,228 Ah-KOw G.213 Ahlrichs R. 23 33 36 Ahmad A. 332 Ahmed A. K. 367 Ahmed M. 87 Ahmed T. Y. 222 Ahond A. 406 Ahmed S. S. 208 223 318 Ahrens W. 73 Ahuja S. 22 Aihara J.-I. 201 Air G. M.,394 Akashi K. 182 315 319 heson A. 361 Akimoto H. 406 Akiyama S. 235 236 237 Akulin Y. I. 254 Akutagawa S. 186 Alagona G. 34 Alagona G. 34 Albert A. 277 Albini A. 96 Albrecht W. L. 267 Alcock W. G. 181 Alder,.A. P. 158 Alexakis A. 179 Alexander C. J. 35 Alexander E. C. 285 Alexander R. W. 424 Alexandratos S. 32 209 Allavena M. 36 Allen G. F. 107 248 Allen L. C. 34 36 37 Allen R. W. 87 224 Allinger N. L. 30 289 Allmann R. 230 Allum K. G. 181 Al-Mukhtar J.382 Al-Neirabeyeh M. 190 Alper H. 91 106 116,241 Alper J. B. 326 Al-Sader B. H. 94 AI-Showiman S. 188 Alste J. 203 Altmann J. A. 24,43 Altus C. 111 295 Alvarez-Insua A. S. 255 Alyev I. Y. 142 Amano A. 230 Ambidge P. F. 81 Amornraksa K.,258 Anastasi A. 353 Anciaux A. J. 118 Anderegg R. J. 355 Andersen J. R. 257 Andersen N. H. 9 Anderson C. D. 50 271 Anderson C. M. 361 Anderson J. E. 199 Anderson P. S. 224 Anderson W. F. 361 Andersson G. 217 Andersson,.J. 148 Ando I. 165 222 226 Anteunis M. J. O. 277 420 Andreasson L.-E. 369 Andreeva N. S. 361 Andresen A. 103 Andrews D. A. 322 Andrews G. D. 47 430 Anet F. A. L. 289 Angyal S. J. 189 Annarelli D.C. 134 243 Ansell J. M. 31 1 Ansevin A. T. 393 Antus S. 210 Aoki K. 95 Apeloig Y. 28 127 Appelqvist L.-A. 22 Appleton D. C. 188 Aprison M. H. 425 Arad-Yellin R. 267 Arai M. 191 323 Araki K. 352 Aratani M. 398 Arcoleo J. P. 325 Ariens E. J. 423 Arimitsu S. 82 Armanath V. 384 Armbruster A. 36 Armenante M. 12 Armstrong V. W. 362 365 366,380 Arnett E. M. 60 Arnett J. F. 398 Arnold D. R. 92 Arnott S. 384 Aroney M. J. 193 Arriau J. 31 Arvidsson L. 362 Asada K. 372 373 Asano R. 212 Asano T. 56 Asao T. 232 Ashby E. C. 63 128,324 Ashe A. J. 136 270 Ast W. 113 Astin K. B. 56 Atherton E. 351 Atkinson R. 301 Atlas D. 424 Atta-ur-Rahman 208 Attina M.209 Atwood J. L. 260 Au A. 266 Aue D. H. 33,35 175 Aue W. A. 16 17 19 Auksi H. 45 Aul’chenko 1. S. 322 Auld D. S. 362 Aumann R. 96 Aurangzeb M. 203 Aurbach G. D. 424 Avasthi K. 132 309 Author Index Avni H. 395 Avram M. 116 Avramenko L. F. 277 Ayer W. A. 410 Ayscough P. B. 81 Azam K. A. 85 Azman A. 37 Azuma Y.,28 Baardman F. 184 Baba A. 109 Baba S. 118 133 170 308 Baba Y. 412 Babin D. R. 41 1 Babitskii B. D. 104 Bach R. D. 194 Backes J. 297 Baclawski L. M. 127 Badawi M. M. 397 Baeckstrom P. 156 300 Bagus P. S. 23 Bahl C. P. 383 393 Bair K. W. 332 Baird M. S. 94 95 175 Baiulescu G. E. 13 Baker M. M. 137 Baker A.D. 44 Baker J. R. 212 Baker R. 186 Bakeyev V. V.,396 Bakuzis M. L. F. 321 Bakuzis P. 321 Balanson R. D. 414 Balcells J. 191 Balchunis R. J. 67 163 Baldassame A. 179 306 Baldwin J. E. 42,47,239,279 335,336 Baldwin J. P. 396 Balvert-Geers I. C. 340 Bampfield H. A. 47 296 Ban Y.,107,248 Bando T. 260 Baney H. F. 177,292 Banner D. W. 361 Baran J. S. 192 335 Barber G. N. 93 Barclay L. R. C. 79 Bard A. J. 234 Barker G. K. 103 Barkovich A. J. 207 284 Barlow L. 304 308 Barlow R. B. 422 Barltrop J. A. 166,266 Barmakova T. V. 12 Barnard F. A. 423 Barnett K. G. 214 Barr P. J. 376 Barraclough P. 198 Barreiro E. 173 Barrell B. G. 394 Barriel J. M. 9 Bany J.E. 137 Bartell L. S. 30 Bartha F. 363 Barthelat J. C. 28 Bartholeyns J. 368 Bartholin K. 101 Bartlett P. D. 41 Barton,D.H. R. 165,216,405 Barton T. J. 121 122 257 Bartschot R. M. 352 Basch E. H. 192 Basha A. 208,223,318 Bass R. J. 267 Basset J. M. 97 114 Bassindale A. R. 325 Bastedo-Lerner D. 388 Bates A. J. 345 Bates G. S. 332 347 Batley K. E. 354 Battersby A. R. 402 Battersby J. E. 343 Battioni J. P.,197 Baudhin P. 368 Baudisch J. 16 Bauer D. 174 281 Bauer D. P. 168,311 Baughman R. H. 42 Bauld N. L. 291 Baumann H. 354 Baumann M. 337 Baumstark A. L. 282 308 Bauschlicher C. W. jun. 34 35 Baxter M. G. 420 Baydar A. E. 50,268 Beam C. F. 253 Beard R.M.,218 Beaucage S. L. 381 Beauchamp C. O. 369 Beaupkre D. 25 Bechara E. J. H. 282,308 Becher J. 259 Bechgaard K. 257 Beck J. R. 265 Becker H.-D. 271 Becker J. Y. 143,219,400 Becker R.-D. 217 Beckett A. H. 4 Beckhaus H. 126 Beckmann B. G. 282 Beem K. M. 372 BCguin F. 214 Behrendt E. M. 365 Beier B. F. 110 Beintema J. J. 367 Beland F. A. 385,386 Beld A. J. 423 Bell E. A. 86 Bellamy F. 277 Bellard M. 396 BelluS D. 184,.329 Belluzzi J. D. 355 420 Bendazzoli G. L. 9 Bender C. F. 34 35 Bender C. O. 157 Bender W. 392 Benioff P. 28 Benn M. 195 Bennett D. A. 335 Bennett G. N.. 381,391 Bennett J. E. 76 Bensaude O. 379 Benson W. R. 157 Bentley R. L.248 Bentley T. W. 55 131 Beran S. 30 Bercaw J. E. 101 Berendsen H. J. C. 388 Berezkin V. G. 12 17 Berg A. 148 Berg C. 257 Berg P. E. 395 Bergbreiter D. E. 133,320 Berger A. 368 Berger S. 216 Bergman J. 249 Bergman R. G. 92 204 240 290 Bergstrom D. E. 376 Bergstrom R. G. 60 Berlan J. 197 Berlin Y.A. 383 Bernard D. 179 Bernardi F. 25,32,33,43 Bernasconi C. F. 213,214 Bern& I. 12 Bernat Zs.Sz. 12 Bernath G. 287 Bernauer K. 397 Berndt A. 73 Bernhardt J. C. 129 322 Berntson G. G. 356 Berry R. S. 85 Berson J. A. 43 47 78 79 296 Bertelo C. A. 101 120 325 Bertie J. E. 228 291 Bertoni G. 12 Bertrand K. 391 Bertrand M. 329 Besl O. 96 Besmer P.392 Besselikvre R. 406 Best W. 283 Bethell D. 64 Betz M. 230 Beugelmans R. 166 225 Bevers J. 13 Beychok S. 365 Bhacca N. S. 100 Bhanu S. 168 Bhattacharjya A. 95 242 Bianchi G. 46 Bickelhaupt F. 41 1 Bieberbach A. 234 Bieile D. M. 362 Biemann K. 355 Bien S. 96 Bienieck D. 257 Biggs I. D. 223 Bigley D. B. 42,194 Bilhou J. L. 97 Binger P. 118 294 Bingham R.C. 62 Binkley J. S. 25 27 28 34 Birch 4.J. 115 Birdsall N. J. M. 356 416 419,421,423 Birenberg M. 418 Birmingham M. K. 7 Birnstiel M. 395 Birshtein T. M. 7 Bischof P. 292 Bishop K. C. 293 Bittner E. W. 60 Bj~rgo,J. B. 188 Bjorkuist D. 43 Bjorkuist L. 43 Blackburn E. H. 394 Blackburn G.M.,378 Blades A. T. 16 Blake J. 349 Blasznak L. 309 Blatcher P. 126 326 Bleich H. E. 420 Blobstein S.H. 385 386 Block E. 198,245 Block T. F. 39 Blomberg L. 15 18 Bloodworth A. J. 129 Bloomer A. C. 361 Bloor J. E. 225 Blount J. F. 272 Blout E. R. 7 Blow D. M. 361,388 Blower P. E. jun. 338 Blum P. M. 74 Blumenthal K. M.,362 Bobbitt J. M. 139 153 Bobek M. 376 Boca J. P. 4 11 Boche G. 234 Bock H. 198 Bock M. G. 135,322 Bode W. 361 Boden R.M. 180 Bohnke E. 380 Boekelheide V. 143 219 Boelens H. 322,338 Boersma J. 122 Boggs J. E. 23 28 186 Bogri T. 41 1 Bohenkamp W. 373 Bohn R. K. 193 Boireau G. 192 313 Boiwe T. 361 Boldrini G. P. 119 324 Bolton P.H. 388 Bolton R. 208 Bolton S. E. 410 Bomse D. S. 186 Bonfiglio J. N. 259 Bonilla A. 233 Bonini B. F. 44 Bonneau R.,156,301 Bonnier J. M. 208 Booth H. 288 Borchardt J. K. 177 292 Borden W. T. 24,29 1 Borders C. L. 362 Bordwell F. G. 55 215 Borel D. 241 Bornstein J. 254 Borremans F. 277 Bors W. 369 371 Boschung A. F. 52 Boshart G. 226 Boss R.,189 Bosse D. 292 BothC-Helmes E. G. 341 Bouas-Laurent H. 226 Bouchet P. 252 Bouman T. D. 3 Bourdais J. 192 313 Bovey F. A. 367 Bovill M. J. 30 Bower H. E. 62 Bower J. D. 419 Bowers C. Y.,353 Bowers J. S. 128 Bowers M. T. 33 35 175 Bowery N. G. 428 Bowlin H. B. 47 Boyajian C. 194 Boyd D.365 Boyd D. B. 10 Boyd D. R.,188 Boyd G. V. 50,268 Boyd J. 190 Boyer H. W. 393 Bozimo H. T. 133 Bracko R. D. 405 Bradbury A. F. 356,357,419 420,42 1,422 Bradbury E. M.,396 Bradbury J. H. 368 Bradley J. N. 81 Brady J. W. 362 Branden C. I. 361 Braga E. A. 395 Branca S. J. 93 Branchini B. R.,362 Branlant C. 391 Brault M. 68 Brauman J. I. 52 324 Braun H. 30 Bravo P. 274 Bray R. C. 370 Brazhnikov V.V. 17 Breek R.,21 Breijer A. J. 184 Brennan T. 387 Brenner D. M. 297 Breslow R.,65 144 202 21 1 Breuninger M. 205 Brewer H. W. 4 11 Author Index Brewster A. G. 216 Brice V.T. 304 Bridgen J. 369,372 Bridges A. J. 45 183 Bneger G. 102 304 Brigelius R.,371 Bnmacombe R.,391 Brinker U.H. 94 Brinn I. M. 223 Brock C. J. 372 Brocker U. 225,267 Brockmann H. jun. 226 Broekhof N. L. J. M. 189 Bromilow J. 203 Brook A. G. 122,325 Brook P. R.,47 296 Brookes P. 385 Brooks D. W. 234 Broom A. D. 384 Brower K. R.,62 Brown A. G. 195 Brown C. 194 Brown C. A. 169 Brown D. M.,76,378 Brown D. R.,288 Brown D. T. 364 Brown D. W. 95 Brown G. 398 Brown H. C. 60 130 131 132 133,168,292,303,311 313,314 Brown K. A. 165 Brown K. D. 391 Brown L. R.,368 Brown 0.R.,137 Brown R. F. C. 46,93 Brown R.H. 162 Brown R.T. 409 Brownbridge P. 199 Browne A. T. 86 Browne C. A. 361 Browne L. J. 336,337 Brownlee G. G. 392 Brownlee R.T.C. 203 Broyde S. B. 382 Brubacker C. H. 181 Bruce E. A. W. 193 Bruice P. Y.,68,203,277 Bruice T. C. 68,69 203 277 Bruna P. I. 24 Brundle C. R. 186 Brunelle D. J. 193 276 331 Bruner F. 12 Brunetti H. 216 Brunton G. 73 79 Bryce-Smith D. 41 166 205 213 Buchecker C. D. 50 Buck H. M. 284 Buddrus J. 93 279 Biichi G. 355 Biichi H. 392 Buenker R.J. 23,24 Biirgi H. B. 290 Author Index Burstinghaus R. 329 Buhler J. D. 128 Bui A.-M. 406 Buis J. T. 341 Bujmicki B. 198 Bull P. 365 Bullivant M. J. 156 Bullock A. T. 74 Buncel E. 214 Bunnett J. F. 213 Bunton C. A. 222 Burdon J. 26 Burgen A. S. V. 421,423 Burger K. 271 Burger V. 96,204 Burgess A.S. V. 419 Burgess A. W. 30 Burgi H. B. 42 Burgot J. L. 128 Burgstahler A. W. 8 9 320 Burgus R.,356,421 Burk P. L. 97 112 Burke L. A. 31 Burke S. D. 195 Burkert U. 289 Burleson D. C. 123 Burlingame A. L. 20 Burnett G. M. 74 Burnett R.E. 100 Burns J. R. 206,266 Burns W. 286 Burrows E. P. 9 Bursey M. M. 33 209 Burt D. R.,425 Burton D. J. 93 Busch A, 49 298 Buss V. 9 Byrom N. T. 118 Byval'kevich 0.G. 214 Cabbat F. 373 Cabrino R.,213 230 Cacace F. 209 Cadet J. 378 Cadger T. 383 Cadogan J. I. G. 86 Cahiez G. 179 Cainelli G. 320 Calabrese L. 370 371 Calas R.,135 Calderon,N. 97,110,178,295 Calo V. 307 Cambie R.C. 2 11 Camerini-Otero R.D.396 Camerman A. 382 Camerman N. 382 Cameron J. R. 395 Cameron L. E. 381 Cammack R.,372 Campbell I. D. 361 Campbell R.M. 188 Campbell S. J. 221 Canonica L. 404 Cantor C. R.,396 Cantrell T. S. 164 Canuel L. L. 367 384 Capon B. 65,66 Capozzi G. 59,169 Capponi G. 13 Capra J. D. 358 Caputo R.,199 Carbon J. 395 Cardillo G. 193 199 320 Carey N. H. 392 Carlberg D. 32 Carlsen P. H. J. 239 Carlson R.D. 396 Carlson R.G. 161 Carlsson R.,249 Carmack M. 254 Carmody M. J. 233 Carnduff J. 279 Caron N. G. 356 Carpenter B. G. 396 Carpenter B. K. 296 Carr D. D. 97 112 Carraway R.,353 Carruthers R.J. 220 Carter,M. J.,45,135,183,314 Cartwight I. L. 380 Caruthers M.H.392 Casagrande C. 404 Casey C. P. 39 101 11 1 Cashion P. J. 383 392 Cassar L. 104 295 Castiglioni M. 110 Castro B. 345,346 Catteau J. P. 277 Caubere P.. 88. I90 Cava M. P. 25,269 Cavazza M. 230,231 Cech T. R.,394 CechovP L. 2 1 Cedheim L. 141 Cesario M. 408 Cessac J. 291 Cha D. Y. 315 Chabalowski C. 25 Chachaty C. 29 Chacko E. 254 Chambaz E. M. 16 Chamberlain,A. T. 17 Chambers J. Q. 149 Chambon P. 396 Chan T. H. 7 135 179 306 Chan T.-L. 218 Chandrasekaran E. S. 181 Chandrasekaran R.,384 Chandrasikaren,S. 3 15 Chang C.-C. 88 121,229 Chang C. J. 64 Chang C.-S. 291 Chang D. 353 Chang J. B. 420 Chang J. K. 420 Chang L. W. K. 59 101 Chang R.C.13 Chang Y. H. 89,270 Chang Y.M.,46,232 Changeux J. P. 422,423 Chao Y.,190 Chapleo C. B. 194 Chaplin M. F. 363 Chapman K.J. 223 Chapman 0.L. 88 121,229 Chapuisat X. 30 296 Charalambides A. A. 409 Chatfield D. A. 209 Chaudhary S. S. 172 Chauvin Y. 11 1 Chau-Wong M. 425 Chebroux P. 16 Chedekel M. R.,121,413 Chen C.-P. 161 Chen H. E. 192 Chen J. 34 Chen L. H. 269 Chen M. C. 387 Chen M. M. L. 26 Chen P. 325 Chen P. S. 354 Cheng C. C. 392 Cheng L. 214 Cheng T. Y.,139 Chern C. I. 327 Cherry W. 28 34 Chesler S. 13 Chevalier P. 114 Chiang C.-S. 133 Chiang G. H. 389 Chiang W. 164 243 Childs R.F. 50 166 Chin-yah Yeh 10 Chioccara F. 253 Chion B. 9 Chiraleu F.I16 Chiu 1.-C.,274 Cho L. 56 Chong A. 0..182 Chou S.-K. 173 Chow Y. L. 217 Chrktien J. R.,12 Christe B. 255 Christoffersen R.E. 25,35 Christopher,T. A. 86 Christy M. E. 224 Chu C. K. 376 Chu K.-Y. 225 Chuche J. 246 Chujo Y.,105 Chum P. W. 183,309 Chung C. S. C. 25 Chung D. Y.,30 Chung L. L. 151 Chupakhin 0.N. 212 Ciarkowski J. 9 Cicciolo P. 12 Cima F. D. 213 Ciranni G. 209 Claeys H. 357 Clapp L. B. 277 Clardy J. 44 157 Clark J. H. 317 Clark T. 232 Clarke L. 395 Clauss P. K. 223 Clayton F. J. 179 Clement E. 37 Clementi E. 32 Clikeman R. R. 288 Clin B. 226 Clive D. L. J. 351 Clizbe L. A. 45 183 Clough R. G. 96 Clough R.L. 202 224 Cocco D. 371 Cocivera M. 192 Coe P. F. 378 Coffin R.L. 161 Coggins J. R. 362 363 364 Cohen J. S. 367 Cohen L. A. 68 Cohen S. 155 280 Cohen T. 215 335 Cohenour P. T. 52 Cohn R. H. 395 Coleman J. P.,137 154 Coleman R. A. 119 Collet A. 9 Collier 0.J. 418 Collin G. J. 230 Collins J. B. 28 34 127 Collins J. F. 427 Collman J. P. 324 Colman R. F. 362 Colonna S. 191 Colpa J. P. 287 Colton C. D. 224 Colvin E. W. 331 Comba M. E.. 12 15 Combs L. L. 28 Commereuc D. 111 Compton D. A. C. 186 Compton R. N. 27 Conan J. 101 Conde G. D. 26 Conde S. 255 Conley R. A. 133 Conlin R. T. 134 243 Connon H. A. 205 Consiglio G. 105 Contrera J.F. 425 Contreras R. 375 393 Cookson P. G. 74,207 Cookson R. C. 186,283 Coombes R. G. 215 Cooper D. 423 Cooper J. W. 74 Coquelet C. 252 Cordes H.-G. 103 Corey E. J. 124 135 189 191 193,276,309,315,316 321,322,330,331,332,333 338,398,414 Corey E. R. 245 Cornforth J. W. 249,360 Cornish-Bowden A. 361 Corral C. 255 Cortese N. 102 Coscia C. J. 402 Costantino,S. M. 260 Cottrell D. M. 157 Coudert G. 88 Coulomb-Delbecq F. 173 Coulson A. R. 394 Coulson C. A. 201 Coulson D. M.,21 Court J. 208 Courtot P.,52 Coutts I. G. C. 216 Couture A. 162 163 Cox B. M.,419,421,422 Cox D. P. 203 Cox N. 6 Coy D. H. 356 Coyle S. 342 343 Cozzarelli N. R. 393 Cozzone P.J. 382 Crabbt P.94 173 Craig J. C. 10 Crain P.F. 389 Cram D. J. 190,276,328 Cram S. P. 11 12 Crampton,M. R. 213,225 Crawford J. L. 360 Crawford T. C. 132 Creed D. 217 Creese I. 418,425 Cremer D. 25 Cresp T. M. 237 Cristea I. 215 Cnstol S. J. 155 Crombie L. 317 Crothers D. M. 388 Crowe H. R. 79,80 Crowley J. I. 85 338 Crumrine A. L. 192,335 Crumrine D. S. 279 Cruypelinck D. 11 1 Csizmadia I. G. 24 31.92 Cue B. W. jun. 260 Cum G. 177 Cunico R. F. 135 179 Curtis D. R. 425,426 427 Curtiss L. A. 37 Cushman M. 355 Cutnell J. D. 420 Cutting J. 239 336 Cuvigny,T. 124,191,195,332 Cvetanovic R. J.. 300 Dadson B. A. 399 DafTorn A. 59 Dagan A. 235 Dagani D. 129 Author Index Dagli D.J. 194 Dagnino M. R. 38 Dahlberg D. B. 63 Dahlhoff W. V. 133 Dalton J. C. 161 Daly D. W. 398 Damasevitz G. A. 133 170 305 Damiano J.-C. 94 Damon R. E. 195 D’Amore M.B. 52 Dan N. 229 Danen W. C. 71 72 Danforth C. 69 Danheiser R. L. 315 Daniel W. E. jun. 384 Danieli R. 211 Daniels M. P.,423 Danishefsky S. 195 330 Dannenberg J. J. 29 33 41 Danyluk S. S. 382 Dargelos A. 31 Darnbrough G. 317 Darwish D. 221 Das. M.K. 130 Daub J. 232 Dauben W. G. 162 Dausse J.-P.. 366,367 Davalian D. 224 David M..362 Davidson A. H. 180 304 Davidson E. R. 23 Davidson N. 392,395 Davidson P. J. 123 Davidson R. S. 164 Davidson W. R. 175 Davies A.G. 74 136 207 Davies D. P. 370 Davies D. W. 26 Davies. R. J. H. 384 Davies R. V. 188 Davis F. A. 245 Davis G. E.. 363. 413 Davis J. H.,92 204 290 Davis J. N. 424 Davis R. W. 390,395 Davis T. D. 28 288 Davis W. H.,177 Davoli D. 395 Davy J. R. 219 Day A. C. 166,266 Day A. R. 420 Day R.A. 148 Day R. O. 382 Deacon G. B. 134 Deakyne C. A. 34 de Alvare L. R. 371 De Angelis F. 92 Debaerdemaeker T. 230 de Bemardo S. 9 de Boer,T. J. 8 280 Debon A, 169 De Camp W. H.. 410.41 1 De Clerq E. 384 Author Index De Crombrugghe B. 394 Deelder R. S. 16 Deeming A..J. 85 Degani I. 127 255 320 de Gee A. J. 8 Degenhardt C. R. 139 Dehmlow E. V. 92 de la Mare P.B. D. 21 1 Delay A. 96 Del Bene J. E. 37 38 Deleris G. 135 Dell A. 357 Dell’Erba C. 226 de 10s Heros V. 96 De Lue N. R. 133,313 DeMark B. R. 70 de Mayo P. 162 163 De Meester P. 344 de Meijere A. 219 292 Deming S. N. 12 Denes A. S. 31,92 Denis J. N. 125 Denney R. C. 11 Denniff P. 323 Dennis N. 41,46 261 276 Dennis R. W. 74 Depew R. E. 394 de Renzi A. 103 de Rossi R. H. 214,225 Derrick P. J. 20 Dervan P. B. 47 135,307 des Abbayes H. 116 Descoins C. 312 Descotes G. 101 114 Deshpande P. D. fll0 de Spinoza G. R. 313 des Roches H. 116 Destro R. 234 DeTar2 D. F. 33 Deur-Siftar D. 21 Deutch J. 423 Devabhakara D. 207 Devaprabhakara D. 132,309 Devaquet A.30,160 Devaquet A. J. P. 28,30 186 227,290 Devlin J. L. tert. 32 Devoghel G. J. 261 De Vrieze G. 367 Dewar M. J. S. 25,41,49,177 De Wied D. 422 Dhawan K.L. 43 Dickens J. P. 214 Dickerson R. E. 393 Di Corcia A. 12 13 Diehl H. 232 Dielmann R. 14 Dietrich C. O. 182 Dill J. D. 24 27 28 37 127 Dinulescu I. G. 116 Dittmer D. C. 245 Di Tullio G. 13 Dixon D. A. 360 Dixon W. T. 2 16 Djarmati Z. 410,411 Djerassi C. 3 Dobbs F. R. 63 Dodd J. R. 225 Dodin G. 379 Doecke C. W. 199 Doel M. T. 392 Donges R. 230 Doering W. von E. 297 Dolbier W. R. jun. 94 Dole D. L. 326 Dolejs L. 399 Dollat J.-M. 173 Dolly J. O. 423 Domagala J. M. 194 Domenicano A. 202 Domingo E.366 Dominic W.J. 206 266 Donatelli B. A. 269 Doneen B. A. 421 Donnelly S. J. 303 Donovan D. J. 34 Doomes E. 218 Dormoy J.-R.,345,346 Dotsevi G. 328 Doucet J. P. 25 Dourtoglov B. 345 Doutheau A. 173 Dowd W. 62 Doyle M. J. 118 294 Doyle M. P. 171 303 Doyle T. D. 157 Drabowin J. 198 Drake A. F. 9 Dray A. 428 Dreiding A. S. 194 Dreyfus M. 379 Driessen P. B. J. 258 Dromey R. G. 20 Drozd J. 22 Drozd V. N. 213 Druelinger,,M. 191 334 Dubois J.-E. 12 202 379 Duc C. L, 21 Dulffer T. 364 Duerinck F. 375 Diirr H. 89 207 226 Duffield A. M. 20 Duggan A. W. 426,427 Dulcere J. P. 329 Dulova V. G. 322 Dumont W. 125 178 306 307,312 Dundulis E. A.328 Dunitz J. D. 42 Dunkerton L. V. 398 Dunkin I. R. 253 Dunn L. C. 46,232 Dunogues J. 135 Dupont W. 239,336 Durand J. 16 Durand Ph. 28 Dun H. 89 Durst H. D. 276 338 Dwight D. J. 19 Dwivedi P. C. 37 Dyall L. K.,223 Dyatkh B. L. 230 Dyke S. F. 224 Dykstra C. E. 24 Dzadzic P. M. 56 Eaker D. 358 Eastwood F. W. 46,93 Eaton P. E. 295 Ebel J. P. 391 Eberle A. 341 Eberle G. 349 Eberson L. 137 138 139 141 148 Ebine S. 231 Echigoya E. 113 Eckert H. 344 Eckler P. E. 45 Eckstein F. 362,365,366,381 Edelman I. 417 Edward J. T. 286 Edwards B. F. P. 360 Edwards J. A. 189 Edwards M. 198 210 Edwards 0.E.,.411 Effenberger F. 234 Effio A. 192 Efros L. S.254 Efstratiadis A. 393 Ege G. 235 Eggimann W. 214 Eguchi S. 92 173 Ehmann W. J. 114,324 Ehrig V. 192 Eichenauer H. 124 191,334 Eickman N. 44 Einig R. G. 15 Eisch J. J. 125 133 170 242 305 Eisele G. 360 Eisenbrand G. 21 Eklund H. 361 El-Abadelah M. M. 9 Elam E. V. 264 Elde R. 422 Elguero J. 31 252 Elliott A. J. 81 Ellison G. B. 28 186 El Muir N. 146 Elstner E. F. 373 Emeis C. A. 6 Emmens M.,367 Endean R. 353 Enders D. 124 135 191,322 332,334 Endo H. 80 Endo M. 135 Endo N. 351 Enfield D. L. 357 436 Engler E. M. 149 English A. D. 102 Enmanyi K. 372 Enna S. J. 425,427 Ensley H. E. 309 Entwhistle I. D. 102 Entwistle D. W. 381 Ephritikhine M.11 1 112 Epiotis N. D. 25 28 32 33 34,43,201 Epstein W. 190 Erdokimov A. M. 254 Erickson B. W. 349,351 Ericsson L. H. 357 Erman M. B. 322 Ermer O. 289 Ermler W. C. 32 Ernest I. 338 Emst M. D. 359 Ernstbrunner E. E. 5 Errede L. A. 265 Erspamer V. 353 Ertl H. 282 Escarmis C. 366 Eschenmoser A. 128 Essiz M. 88 Ettre L. S. 11 14 Evans B. R. 216 Evans D. A. 132 220 298 308 Evans D. R. 360 Evans F. E. 381 Everett J. R. 288 Evin G. 345 346 Ewing G. D. 233 Exner H.-D. 174 Exner O. 202 Eyem J. 20 Ezra F. S. 382 Fabry M. 367 Fairbanks G. 363 Fairclough C. S. 64 Falk H. 128 Fanning M. O. 25 Faragher R. 254,262 Fareed G. C. 395 Farid S.,165 Farina E.213 Farina V. 230 Farkas L. 210 Farneth W. E. 52 160 Farnham W. B. 287 Farona M. F. 97 112 Farooqui T. A. 223 Farr F. R. 291 Farrell P. G. 286 Farre-Rius F. 16 Farrow J. T. 423 Fasold H. 363 Fauchtre J.-L. 341 Faulkner J. D. 148 Favre B. 133 Fawcett J. K. 382 Fazal N. A. 74 Fedak S. A. 424 Fedora A. A. 361 Fee J. A, 371 373 Fehlhammer H. 361 Fehlner T. P. 177 292 Fehrle M. 346 Feigel F. 231 Feinberg A. P. 418 Fejes P. 20 Felix D. 427 Felix G. 226 Fell B. 283 Fellner P. 391 392 Felsenfeld G. 396 Felt G. R. 90 Felzenstein A. 270 Fenske R. F. 39 Fentiman A. 223 Fenzl W. 131 Fernlund P. 354 Feron A. 96 241 Ferrari R.P. 110 Fertel R. 356 Fessenden R. W. 77 81 82 Festa C. 230 Ficini J. 167 338 Fiddes J. C. 394 Field D. J. 50 Fielden E. M. 370 373 Fields T. R. 155 300 Fiers W. 375 383 390 395 Fietz L. F. 330 Fife T. H. 70 Figuera J. M. 35 Fikus M. 384 Filipescu N. 157 Filler R. 212 277 Filosa M. P. 337 Finch J. T. 396 Fink W. H. 34 35 Finke R. G. 324 Finkelstein M. 137 Finklestadt W. R. 367 Fiorini M. 100 Firestone R. A. 46 239 Firth B. E. 153 194 Fischer A. 210 Fischer E. O. 96 111 112 Fischer J. 275 Fisher R. D. 62 Fitzpatrick J. M. 330 Fitzpatrick N. J. 25 Fitzwater S. 30 Fleming I. 41 45 86 135 183,217,304,314 Fleming M. P. 308 Fleming R. H. 47 Fletterick R.J. 361 Fliszbr S. 28 288 Flitsch W. 247,256 Author Index Flood,E. 33 Flossmann W. 31 Floyd A. J. 224 Flurry R. L. jun. 38 FOB,M. 104 Fochi R. 127,255,320 Fodor L. 268 Fokhin A. V. 277 Folkers K. 353 Follmann H. 380 Fong B. W. T. 420 Fonken G. J. 177 Fonzes L. 4 11 Foote C. S. 374 Ford,M. E. 133,193,242,327 Fornasier R. 191 Forrest D. 79 Forrester A. R. 78 92 241 Forte P. A. 222 Fortes C. C. 321 Foster C. H. 264 Foster M. 362 Fothergill L. A. 355,418 Fournier M. 36 Fowden L. 413 Fowler F. W. 259 Fowler K. W. 215 Fox J. J. 376 Franck R. W. 79 Franck-Neumann M. 50 Frandsen E. G. 259 Frank A. 130 Frank G. 275 Franken J. J. 15 Frank-Kamenetskii M.D. 393 Franzus B. 47 Fraser R. R. 43 Frater G. 190 250 310 Fravel H. G. 155 300 Frazier J. 384 Fredga A. 10 Freed J. H. 82 Freedman H. H. 319 Freer R. J. 420 Freisheim J. H. 362 Frejd T. 255 Frenette D. A. 28 288 Fridkin M. 392 Fridovich I. 368 369 370 371,372,373 Friedrichsen W. 230 Friedricks P. 363 Friend E. W. jun. 233 Frimer A. 212 Frischknecht W. 21 Fristad W. E. 44 Fritz D. F. 13 14 Fritz H. 205,358 Fritz H.-J. 383 Froentjes W. 21 Fromageot P. 366 367 Frost A. A. 28 288 Fry A. J. 151 204 Fry J. L. 62 303 Author Index Fryer R. I. 250,272 Fu T.-H. 102 304 Fuchigami T. 89 15 1 Fuchikami T. 122 Fuchs P. L. 333 Fuchs S.423 Fueno T. 32,45 Fujii C. R. 182 Fujii T. 401 Fujiki H. 365 Fujimoto H. 41 42 293 Fujimoto Y. 303 Fujisawa T. 3 13 Fujise Y.,231 Fujita E. 317 Fujita H. 366 Fujita K.,186 Fujito H. 262 Fujiwara Y.,212 Fukata G.. 212 Fukazawa Y. 220 Fukuda N. 263 Fukui K.,41,42,235,285,293 Fukumoto K.,45 Fukutome H. 27 Fukuyama T. 398 Fukuzumi K.,102,113 Fulcher J. G. 307 Fulpius B. W. 423 Fu-Ming Chen 9 Funakura M. 50 Funamizu M. 232 Fung D. 164,243 Funk R. L. 45 102 171,207 224,226 Furuhata K. 7 Furukawa J. 45 117 Furukawa M. 260 Furukawa N. 10 Fyfe C. 192 Gaffney J. S. 301 Gait M. J. 383,393 Gajewski J. J. 47 Galibert F. 394 Gall J. H. 66 Galle J.E. 125 242 Galley M. W.,209 Gallucci R. R. 94 Galpin I. J. 345 Game C. J. A. 427 Ganem B. 194,207 Ganem D. 395 Gano J. E. 159 Garanti L. 44 Garbay-Jaurguiberry C. 420 Gardano A. 104 Gardlik J. M. 233 Gardy E. M. 78 Garito A. F. 269 Garratt D. G. 169 Garratt P. J. 207 224 Garrett R. A. 390 391 Garsky U.,355,420 Garst J. F. 47 Garza 0.T. 94 Gaspar P. P. 134 243 Gassman P. G. 67 97 111 112 114,295,296 Gastra W. 367 Gates B. C.. 172 Gaudemar M. 173 Gause G. G. jun. 393 Gavrichev V.S. 12 Gawley R. E. 338 Gawronski J. K.,9 Gayda R. 395 Geckle J. M.. 233 Geevers J. 256 Gehret J. C. E. 96 Geiger R. E. 7 341 Gelas-Mialhe Y. 241 Gelboin H.V. 385 Geller R. B. 353 Gellert M. 394 Genco N. 115 Gender A. 235 Gent J. P. 352 Gentleman S. 422 George M. V. 277 George W. O. 186 Georgiev G. P. 396 Gera L. 287 Gerace M. J. 282 Gerlach H.,330 Germond J.-E. 396 Gerson F. 219 Gesing E. R. 247 Gewald K.,256 262 Ghosh S. S. 132 309 Giacomello P. 209 Gianni F. L. 45 217 Gibbons W. A. 420 Gibbs H. W. 210 Gibson T. W. 185 Giddings M. R. 5 Giegk R. 387 Giffney J. C. 209 Gifkins K. B. 157 Gil G. 329 Gil-Av E. 226 Gilbert A. 41 166 205 213 Gilbert H. F. 362 Gilbert J. C. 157 299 Gilchrist T. L. 50 94 198 254,262 Gileadi E. 152 Gilgen P. 251 Gilham P. T. 381 383 Gillam S. 392 Gillespie D. G.86 Gillon A. 96 Gilman N. W. 272 Giongo G. M. 100 Giovagnoli C. 373 Girke W. 265 Givens R. S. 161 Gittos M. W. 188 Gladysz J. A. 87 307 Glasel J. A. 420 Glass G. P. 80 Glass J. D. 343 Glass R. S. 208 Glatt I. 49 Gleghorn J. T. 32 Gleiter R. 44 Glenn T. H. jun. 12 Glonek T. 382 Glowinski R.,214 Glyde E. 262 Goda K. 371 Goddard W. A. tert. 24 92 290 Godfrey M. 212 Godleski,S. A. 286 Goerdeler J. 253 Goering H. L. 133 Goff D. 420 Gokel G. W. 276,338 GolaS T. 384 Goldberg D. E. 136 Goldberg I. B. 79 80 Goldfarb Ya. L. 277 Golding J. G. 215 Goldschmidt E. 49 Goldstein A. 417 419 421 422 Goldstein J. S. 419 Goldthwait,D. A. 365 Gombacorta A.92 Gombos J. 330 Gompper R. 49,229,232 Goodfriend L. 358 Goodin R. 65 144 Gooding K. M. 14 Goodman F. J. 149 Goodman H. M.,393 Goodman P. A. 212 Goodwin R. 202 Goody R. S. 381 Gopinath K. W. 45 Gordon A. L. 16 Gordon M. D. 270,288 Gordon M. S. 24 Gori J. 173,3 11 Gore P. H. 212 Gorenstein D. G. 29 Goretti G. C. 12 Gorgues A. 167 Gorski R. A. 194 Gosavi R. K. 31,92 Gossauer A. 196 Gotoh O. 393 Gottarreli G. 9 Gotthardt H. 245 255 257 Gottlieb R. 146 400 Gotto A. M. jun. 350 Gotze S. 268 Gough G. R. 381 Gourcy J. G. 150 Goursot A. 28,288 Goutarel R. 408 Gouverneur P. 208 Grace D. S. B. 204,258 Graham A. 362 Graham L. T. 425 Graham W.D. 96 Grampp B. 365 Granelli I. 402 Grant D. 286 Grant D. W. 14 Grant N. 355,420 Gras J. L. 189,316 Graydon W. F. 97 Grayson J. I. 126 326 Grayston M. W.,203,280 Green B. S. 267 Green D. C. 149 Green L. R.,66 Green M. L. H. 103,111,112 Greenacre G. C. 64 Greenberg D. A. 425 Greenberg R. S. 33 Greene J. 362 Greenhalgh R. 18 Greenlee W. S. 112 Greenzaid P. 57 Gregory H. 359 Greuter H. 184,329 Gribble G. W. 87,224 Griew P. A. 114,195,324 Griesbaum K. 281 Grieve D. McL. A. 66 Griffin A. C. 41 Griffin G. W.,93 Griffin L. L. 28 Griffiths J. 225 230 Grigg. R. 118 Grigorenko T. F. 277 Griller D. 79 208 Grimaldi J. 329 Grimbert D. 30 Grime W.,298,299 Grimmer M.26 Grob C. A. 56 Grob G. 15 Grob K. 15 Grobel B. T. 329 Groen G. 367 Grohmann K. G. 274 Gronowitz S. 255 Gros W. A. 157,299 Groscin S. 369 Grosjean H. 388 Gross B. 190 Gross H. J. 388 390 Gross K. 395 Grossberg A. L. 362 Grossman D. 13 Grout A. 63 Grover S. K. 92 Grubbs R. H. 97 112 181 Gruchshina A. E. 361 Gdyic Z. 144 Grund H. 322 Grundon M. F. 313,414 Grushka E. 11 Grzejszczak S. 180,304 Guanti G. 226 Gunther H. 289,298 Guest K. P. 419 Guggisberg A. 397 Guggisberg H. 56 Guha 0.K. 21 Guichon G. 16 Guida W. C. 313 Guilhem J. 408 Guillaumet G. 88 Guillemin R. 356,419 421 Gunning H. E. 92 Gupta A. 37 Gupta P. 268 Gupta R.C. 390 Gupta R. K. 277 Gurupada D. 28 Gurward S. K. 351 Gustafsson,K. 2 17 27 1 Gutman I. 223 Guttman H. N. 352 Guy P. 21 Guyot A. 101 Gynane M. J. S. 136 Habeeb J. J. 320 Habener J. F. 359 Haber F. 374 Habefield P. 35 192 223 Haberkamp T. J. 279 Haddadin M. J. 276 Haddon R.C. 24 Haegeman G. 375 Hafner K. 230 232 Hagakawa Y. 412 Hagaman E. W. 406 Hagelee L. A. 179 Hagihara N. 103 117 Hagler A. T. 30 Hahn B.-S. 378 Hahn R. C. 209 Haines A. H. 338 Hajdu J. 363 Hajdu R. A. 92 Halevi E. A. 41 228 Halgren T. A. 33 Hall C. D. 378 Hall D. O. 369 372 373 Hall E. A. H. 148 Hall G. G. 35 Hall J. L. 304 Hall R. C. 12,21 Hallcher R. C. 137 Hallett A..345 Author Index Halliwell B. 373 Halpert J. 358 Hamada T.. 164,243 Hamaguchi M.,96 Hamana M. 262,269 Hamblin M.,216 Hambrook J. M.,420 Hamer G. K. 203 Hamilton E. J. 37 Hamilton G. A. 171 Hammerich 0.. 142 Hamon D. P. G. 287 Han Y. H. 358 Han Y.-K. 135 Hanack M. 59 Hancock R. D. 181 Hanwck W. S. 343,350,351 Hanley R. N. 252 Hannan B. N. B. 21 1 Hansen H.-J. 220 Hansen R. E. 148 Hanzawa Y. 205 Harada K. 263 Harada N. 7 Harbison K.G. 60 Harder J. W. 52 Harder R. 89 Harding D. R. K. 343 Harding J. D. 365 Harding L. B. 24 Hardy P. M. 340 Harger M. J. P. 197 Hargrave K. D. 130 Hariharan P. C. 26,290 Harlow R. L. 261 Harlter P. 10 Harpp D.N. 306 Hams C. J. 198 Harris D. H. 136 Harris F. W. 16 Harris J. I. 369 372 Harris J. M. 62 Hams J. W.,122 Harris S. J. 134 Harris T. V.,119 Harrison C. R.,131 181 Harrison J. H. 362 Harrison J. J. 79 Harrit N. 253 Hart H.. 60 61 Hartan H.-G. 228,291 Hartcher R.,43,208 Hartigan M. J. 14 Hartkopf A. 13 Hartmann G. R. 365 Hartmann,H.J. 254,269,371 Hartmann J. 43 127 Hartshorn S. R.,62 Hartsuck J. A. 360 Harvey J. A. 425 Harvey R.G. 385,386 Hasan I. 259 Hasegawa T. 388 Haselbach E. 27 Author Index Hashidzume H. 222 Hashimoto H. 105 210 Hashimoto S. I. 128 191,325 Hasinski S. 18 Haslanger M.. 158 Haslinger E. 330 Haslouin J. 325 Hattori M.384 Hauptman H.. 94 Hauser D. 424 Haveaux B. 281 Havel J. J. 94 Havron A. 368 Hawkes G. E. 138 Hawkes S. 13 Hawkins C. 225 Hayashi T. 99 Hayatsu Y.,210 Hayes J. M. 20 Hayes M. B. 367 Haynes R. K. 165 Hayse D. C. 182 Hearn M. J. 281 Hearst J. E. 394 Heasley G. E. 182 Heasley V. L. 182 Heather J. B. 194 Hecht S. M. 379 Heck R. F. 102 Hedgecock H. C. 133 Hegedus L. S. 107 216 248 Heger K. 299 Hehre W. J. 24,28,30,32,41 91,186,209,227,290,291 Heidrich D. 26 Heikkila R. A. 373 Heil A. 365 Heimbach P. 109 Heinrich F. 201 Heinzelmann W. 25 1 Held W. 112 Helder R. 255 Heldeweg R. F.. 44 104 293 Helgeson R. C. 190 Heller H. G. 52 Helmchen G.199 Hempel A. 373 Hendrickson J. B. 332 Henes G. 216 Hengesbach J. 130 Hengge E. 151 Henne W. 275 Henniker J. 16 Henning R. 124 Henninger M. 90 Hennion G. F. 173 Henry L. E. A. 373 Henry-Basch E. 313 Hentschel M. 256 Herberich G. E. 130 Herbert R. B.. 402,405,413 Herbut M. H. 382 Herdle W. B. 201 Hermolin J. 152 Hoheisel C. 33 Hernandez L. 189,244 Hojo K. 253 Herndon W. C. 223 Holbert G. W. 207 Herriott J. R. 361 Holderith J. 12 Herwig J. 103 Holeman M. 275 Herzfeld F. 365 Holendovh O. 21 Hess B. A. jun. 229 Holingren A. 361 Hesse M. 397 Holland H. L. 3 17 Hevesi L. 312 Hollitzer O. 346 Heyneker H. L. 393 Holloman M. 28 Hiberty P. C. 32 Holloway R. 291 Higley D.P. 181 Holm A. 253,277 Higuchi R. 393 Holman R. J. 138 147 154 Hildenbrand P. G. 373 Holmes A. B. 3 11 Hiley C. R. 423 Holmes D. S. 395 Hill H. A. O. 362 Holmstedt. B. 20 Hill H. H. jun. 17 21 Honda M. 205 Hill R. C. 369 Hondo K. 90,251 Hill R. G. 427 Hoogenboom B. E. 252 Hillard R. L. 86 Hooper E. A. 363 Hiller J. M. 417 Hooz J. 179 308 Hindley N. C. 322 Hopf H. 175 219 Hine J. 66 Hopkins H. P. jun. 35 63 Hines L. F. 104 Hoppin C. 97 112 Hingerty B. 382 Hori H. 317 Hino H. 139 Hori T. 182 Hirao K. 271 Horita H. 218 219 Hirata Y.,189 316 409 Horiuchi S. 100 Hirayama T. 263 Hornback J. M. 158 Hiro E. 326 Hornemann U. 216 Hirsch R. H. 163 Hortmann A. G. 95,242 Hirsch W. 196 Hoshino M. 162 163 Hiskey R. G.343 Hosokawa T. 107,258 Hitchcock S. E. 364 Hosomi A. 135 207,314 Hixson S. S. 157 Houk K. N. 32 41 46 156 Hjelmgreen T. 362 161,186,232,293 Hloiek V. 13 Houminer Y. 58 222 Ho C.-T. 96 Houwing H. A. 252 Ho K. 162 Hovland A. K. 122 Ho T.-L. 90 319 321 Howard F. B. 384 Hoberg H. 123 Howard J. A. K. 76 103 Hobolth E. 154 Howard J. B. 357 Ho Chang S. 14 Howard K. A. 164 Hocks L. 113 Howarth T. T. 195 Hodge P. 181 Howell I. V. 181 Hodges R. S. 349 Howell J. M. 24 31 Hodgson D. J. 344 Howie J. K. 373 Hodgson E. K. 371 373 Hoy R.C. 208 Hodgson P. K. G. 67 Hoyle C. E. 163 Hodler M. 150 Hozumi T. 252,380 393 Hoefnagel A. J. 203 HiivniiE M. 21 Hoefnagel,M. A. 203 Htay M. M.,276 Hohn E. G. 3 Huang S. L. 319 Hoffman,J.M. 220,298 Huber K. 410 Hoffmann H. M. R. 49,298 Huber R. 361 Hoffmann R. 26 38 43 95 Hubert A.S.,96 113 118,241 96.297 Hucho F. 363 Hoffmann W. 337 Hudec J. 4 5 8 Hofman E. 363 Hudrlik A. M. 325 Hofmeister P. 135 Hudrlik P. F. 325 Hogen-Esch T. E. 64 Hudson C. W. 94 Hogeveen H. 44 104 204 Hudson D. 345 258,292,293 Hudson H. R. 313 Hohage H. 253 Hudson R.,A. 295 440 Hugelin B. 109 Huggins M.-A. 310 Hughes A. N. 258 Hughes J. 355,418,419,421 Hughes R. 130 168 311 Hughes R. E. 245 Huisgen R. 46 51 239 Hull L. A. 171 Hull R. 262 Hullot P. 195 Hulme E. C. 356 416 419 42 1,422,423 Hulshof L. A. 9 Humayun Z. 395 Humbel D. R. E. 354 Humphreys R. W. 92 Humphries J.353 Hunt K. 47 296 Hurwitz S. 11 1 Huselton J. K. 44,96 Husimi Y.,393 Husmann H. 14 Husson H. P. 406 Hutchings M. G. 129 Hutchinson C. R. 413 Hutchinson D. W. 380 Hutchison C. H. tert. 394 Hutchison G. I. 230 Hutley B. G. 288 Huttner G. 130 Hwang D. R. 295 Ibata T. 96 Ibel K.,396 Ibrahim B. 261 Ichikawa K. 113 Ichikawa M. 110 Ichikawa S. 247 Ichimura H. 9 Ichimura K.,247 Iddon B. 188 I’Haya Y. J. 24 Ikeda M. 92,249,262,316 Ikeda T. 248 Ikeda Y.,105 Ikota N. 318 llenda C. S. 155 Ilie V. A. 13 Imagawa M. 222 Imahashi Y.,95 Imahori K. 367 Imai H. 101 102 Imamura K. 247 Imashiro F. 219 Imhoff M. A. 59 Inagaki S. 41,42 293 Inamoto N. 203 Ingold K.U.71,72,73,74,79 208 Inone S. 398 Inoue T. 323 Inoue Y.,105,158 Inouye Y. 187 Ioffe B. V. 212 Ippen J. 224 Iqbal A. F. M. 91 Ireland R.E. 190 Irwin M. J. 361 388 Irwin R. S. 300 Isaacs N. S. 184,211,276 Isenhour,T. 13 Isenring H.-P. 128 Iserentant D. 375 Ishida A. 260 Ishidoya M. 131 Ishihama A. 365 Ishikawa H. 45 Ishikawa M. 122 Ishikawa N. 118 Ishikura H. 388 Isidorov V. A. 2 12 Issidorides C. H. 276 Itahara T. 216 Itakura K. 393 It8 S. 220 231 270 Itoh I. 287 Itoh M. 131 137 169 332 Itoh N. 318 Ittel S. D. 102 Ives J. L. 165 Iwadare S. 409 Iwakuma T. 318 Iwamura H. 95,204,219,246 Iwanaga S. 358 Iwata K.,89 151 Iyoda M.235,236,237 Jablokoff H. 256 Jack A. 387 Jackels C. F. 23 Jackson A. E. 102 Jackson A. G. 346 Jackson S. 171 Jackson-Mully M. 274 Jacob P. 131 Jacobsen C. S. 257 Jacobson U. 231 Jacques J. 9 Jacquet I. 192 Jacquier R. 252 Jager V. 322 Jakubetz W. 35 JalIo L. I. 222 James B. G. 308 James B. R. 100 James D. E. 104 James J. C. 69 Janlk J. 2 1 Janiga S. 15 Janion C. 384 Author Index Janot M.-M. 406 Janzen A. F. 202 Jaouen G. 115 Jardetzky O. 382 Jarre R. L. 34 Jarvie J. O. 9 Jastrzebski J. T. B. H. 214 Jay E. 383,392,394 Jayalekshmy P. 85 Jean Y.,30 296 Jeffares M. 162 Jefford C. W. 52 96 Jeffrey A. 395 Jeffrey A. M. 385 386 Jeffs P.W. 404 Jeger O. 158 Jemmis E. D. 28 127 Jenkins I. D. 380 Jenkins J. A. 47 Jennette K. W. 385 Jennings B. M. 241 Jennings C. A. 124 Jennings P. W. 304 Jennings W. B. 188 Jensen H. H. 38 Jensen J. L. 182 Jensen L. H. 361 Jerina D. M. 386 Jernberg K. M. 126 Jesson J. P. 102 Jessup P. J. 45 183 220 Jochims J. C. 174 Jonsson B. 37 38 Jornvall H. 361 Johansson O. 422 John I. G. 193 Johns S. R. 414 Johnson C. D. 277 Johnson C. N. 361 Johnson T. H. 97 111 112 114,295,296 Johnson W. S. 178 Johnston G. A. R. 425,427 Johnston J. 426 Johnston J. C. 148 Johnston J. P. 410 Johnston K. 13 Johnstone R. A. W. 102 Jolidon S. 220 Jones A. S. 376 Jones B. L. 358 Jones C.R. 388,420 Jones D. W. 50 90 217 Jones G. 160 Jones L. D. 124 207 Jones M. jun. 94 95 Jones R. C. F. 402 Jones T. B. 177 Jones W. D. 267 Jones W. M. 94 Jongejan E. 280 Joonson V. A. 18 Jordan F. 27 29 Jordan K.D. 38 Author Index Jorgensen W. L. 30 338 Jorritsma H. 258 Joseph T. C. 217 Joule J. A. 406 Joussot-Dubien J. 156 301 Judy W. A. 97 110 178,295 Jiirgens H. J. 230 Jung G. 10 Jung M. E. 45 121 183,190 319,338 Juvet R. S. jun. 11 Kaba R. A. 72,74 Kabalka G. W. 130 133 338 Kabanov V. A. 103 Kabengele T. 96 Kabuto C. 236 Kadlec O. 12 Kafatos F. C. 393 Kagan H. B. 123 Kagan J. 194 Kai Y. 274 Kaiser E. M. 253 262 Kaiser R.E. 16 Kajigaeshi S. 241 Kakimoto M. 24 1 Kakoi H. 398 Kalabina L. I. 18 Kalbacher H. 419 Kalchschmid F. 60 Kaleja R. 380 Kalfus K. 202 Kallenbach N. R.,384 Kallos J. 41 1 Kalvoda J. 321 Kamada M. 263 Kamata K. 193 327 Kambara T. 12 Kame] M. 93,279 Kametani T. 45 400 Kamimori M. 208 Kaminker M. A. 384 Kaminsky W. 103 Kamiyama Y. 122 Kanazawa H. 265 Kanazawa R. 320 Kanemasa S. 241 Kanematsu K. 165 226 Kanfer S. 215 Kannan R. 86 Kantrowitz E. R. 362 Kapadi A. H. 410 Kapila S. 19 Kaplan M. L. 159 218 Kar D. 29 Karafiloglou P. 277 Karanewsky D. S. 221 Karasek F. W.,21 Karich G. 174 Kariv E. 152 Karlishev A. V.. 395 Karlstrom G. 37 38 Karten M.J.127 Kasahara A. 263 Kasai H. 385 386 388 389 Kasai M. 423 Kasai N. 274 Kasai Y. 346 Kaschig J. 346 Kastin A. J. 356 Katagiri N. 393 Katakami T. 235 285 Kato K. 189 316 Kato M. 50 Kato N. 220 Katritzky A. R. 31 41 46 246,261,276 Katsumi M. 8 Katsushima T. 294 Katz J.-J. 132 Katz M. 139 Katz T. J. 97 111 112 204 205,295 Katzenellenbogen J. A. 192 335 Kaufman J. J. 29 Kaufman R. J. 253 Kaufmann H. 321 Kaupp. G. 159,205,218,219 Kaura A. C. 95 Kawabata N.. 279 Kawabata Y. 101 Kawai M.,8 Kawakarni K. 101 Kawakarni M. 248 Kawamori M. 271 Kawanisi M. 294 Kayama Y.,234 Kayser M. 101 196 329 Kayser R. H. 68 Kazimierauk Z. 384 Kazinoti P.I. 196 Kazlauskas R.,402 Kazyak L. 20 Keana J. F. W. 45 Kearns D. R. 388 Keay R. E. 171 Kedes L. H. 395 Kee S. G. 393 Keehn P. M. 220,332 Keele B. B. 372 373 Keeley D. E. 282 336 Keese R. 279 Kehoe J. M. 358 Keil F. 33 Keilin D. 369 Keller O. 342 Kellogg R.M. 277 Kelly D. P.. 60 Kelly R. C. 315 Kemmer T. 226 Kemp D. S..340,341 Kempe T. 199 Kemper B. 359 Kemper R. 165 441 Kenner G. W. 342,345,346 Kensler T. T. 72 Kent H. A. jun. 354 Kent S. B. H. 364 Kerber R.C. 113,214 Kerr C. M. L. 74 KertCsz M. 37 Kessick M. A. 62 Kessler H. 49 195,231 297 Kestner M. M. 214 Kevan L. 77 Keyser G. E. 379 Khabashesku V. N. 121 Khan E. A. 168 Khan M.S.,268 Kheifits L. A. 322 Khetan S. K. 277 Khmelinskaya A. D. 214 Khodakov Yu.S. 178 Khokhar A. Q. 4 Khor T. C. 203 Khorana H. G. 383 392 393 Khuong-Hua F. 408 Khuthier A. H. 222 Kieboom A. P. G. 184 Kieaykowski G. R. 334 Kiefer E. F. 177 297 Kiener P. A. 361 Kihara H. 215,219 Kiji J. 117 Kikuchi O. 52 Kikugawa Y. 406 Killough J. M. 320 Kim B. 164,243 Kim J. J. P. 382 Kim S. H. 36,387,388 Kim S. S. 74 Kimble B. J. 20 Kimpenhaus W. 93,279 Kimura A. 235 ffirnura T. 371 Kinast G.. 330 Kinberger K. 130 King A. O. 133 170 King D. 370 King F. D. 215 King H. W. S. 385 King J. W. 21 King T. J. 195 King-Brown E. H. 157 Kinoshita K. 89 Kiper M.365 Kirby A. J. 67 69 70 Kirchhoff R. 320 Kiricsi I. 20 Kirk D. N. 5 8 Kirschenbaum L. J. 31 Kirschner S. 41 Kisch H. 96 Kiselev A. V. 12 Kjshi Y. 221 398 Kispect L. D. 27 Kiss A. 12 Kitahara T.. 195 330 442 Kitahara Y.,232 234 236 284 Kitschke B. 232 Kitsuya. Y. 139 Klabunde K. J. 123 128 Klappenberger J. 363 Klasek A. 399 Klassen G. R. 381 Klecha C. J. 63 Klee W. A, 418,422 Kleid D. G. 383,395 Kleier D. A. 34 69 360 Kleinschmidt A. K. 390 Klemm L. H. 45 Klenk H. 234 Klepikova V. I. 104 Kleppe K. 392 Kleppe R. 392 Klessing K. 204 Klett R. P. 423 Klima M. 16 Klopman G. 34 Klotz G. 390 Klug A. 387 396 Klug H.-H. 225 242 Kluge A.F. 189 Klump H. 384 Klumpp G. W. 96 Klyne W. 3 5 Knapp S. 124,245 321 333 Knaus G. 193 327 Kneen G. 50,217 Knifton J. F. 104 Knight D. W. 196 Knipe A. C. 222 Knowles J. R. 361 Knunyants I. L. 142 Knyazev V. N. 213 KO E. C. F. 58,222 Kobayashi G. 262 Kobayashi H. 204 Kobayashi S. 156 222. 248 260 Kobayashi Y.,205,269. 380 Kober H. 89 Kobuke Y.,45 Kobylecki R.J. 277 Koch H. F. 63 Koch T. H.. 164 Kochenour W. L. 38 Kochi J. K. 76 177 Kocienski P. J. 311 Konis G. 12 Kodama K. 12 Koebernick W. 126 Kobrich G. 174,281 Kohler H. J. 26 Kolbl H. 228 Kolle U. 130 Koenig K. E. 190 Koster R.,131 133 179 Kofron W. G. 127 Koga K. 128 191 325 Kogure T.100 Kohen S. 96 Kohn H. 21 1 Kojima H. 234 Kok P. M. 216 Kokfelt T. 422 Kolb E. 372 Kolbinger H. 272 Kolc J. 88 121 235 Kolkenbrock H. 363 Koller J. 37 Koller W. 207 Kolomiets A. F. 277 Komaki R. 219 Komatsu K. 218 231 Komatsu M. 258 Komin A. P. 254 Komiya M.,358 Komornicki A. 30 49 Kon E. 216 Kondo K. 326 Kondo N. S. 382 Kongkathip B. 118 Konishi K. 425 Konno T. 7 Kbno M. 22 Kono Y. 373 Konst W. M. B. 338 Konze-Thomas B. 365 Koob R. D. 24 Koosha K. 197 Kopilov J. 152 Koppenol W. H. 374 Kopperschlager G. 363 Koreeda M..386 Korinek K. A. 338 Kormer. V. A. 104 Kornbium N. 214 Korte D. E. 216 Korte F. 257 Korver 0.,6 Koski W.S. 29 Kosterlitz H. W. 355 418 419,421 Kourilski P. 393 Kouwenhoven A. P. 184 Kovacic P. 172 Kovaleva N. V. 12 Kovar R. 324 Kovlts E. Sz. 14 Koyama K. 89 Kozarich J. W. 379 Kozerski L. 289 Kozikowski A. P.. 99 Kraemer H. P. 221 Kramer G. W. 131 Kramer J. D. 206 Krantz A. 92 Krapcho A. P. 328 Kraus G. 42 184 309 Kraus G. A. 323 Krause S. 123 Krebs A. 165 Kreeger R. L. I2 i Kreigh H.. 6 Author Index Kreissl F. R.,96 Kress T. J. 260 Krestonosich S.,166 213 Kresze G. 46 Kretchmer R. A. 214 Kricheldorf H.R. 346 Krief A. 125 178 303 306 307,312,316 Krieg. B. 250 Krieger D. E. 351 Krieger R. L. 204 Krischnamurthy S.,303 313 314 Kristaponis J.357 Kristin M. 15 Kmjevic K. 425,427 Krohnke F. 277 Krol A. 391 Krolikiewicz K. 377 Kroner J. 229 Kropp P. J. 155 300 Krowicki K. 248 Kruaynski L. J. 202 Kruger C. 96 Krugh T. R. 382 Kruptik J. 15 Kruse C. G.. 189 Kruse L. 239 336 Ku A. 44,240 Kubei B.,268 Kubisa P. 190 Kuebler N. A. 186 Kuchler E. 391 Kupper H. 393 Kugucheva E. E. 13 Kuhar M. J. 417 424 425 427 Kuimova M. E. 133 Kumada M.,99 122 Kumadaki I. 205,269,380 Kumagai M. 100 Kumar A. 207,392 Kumbar M.,36 Kunerth D. C. 214 Kunz H. 340 Kuper H. 367 Kupper F.-W. 113 Kurachi K. 361 Kuramoto M.,406 Kurath P. 355 Kurihara H. 232 Kurihara T. 193 243 331 Kurita J. 264 Kuroda Y.,95,276 Kurtz W.260 Kurz M. E. 210 Kushibiki N. 76 Kushida K.,95 Kutschan R.,196 Kutzelnigg W. 33 Kuwajima I. 134 191 323 Kuyper J. 127 Kuzuya M. 60,61 Kwant P. W. 292 Author Index Kwantes P. M. 96 Laverty D. T. 112 Kwart H. 63 Laviron; E. 146 Kwon S. 92 249 262 Law D. C. F. 281 Kyba E. P. 94 197 Lawrence A. H. 162 Lawton R. G. 158 Lazarus L. H. 356 Lazurkin Y. S. 393 Leander K. 402 Leary J. 13 Laarhoven W. H. 157 206 Le Borgne J. F. 124,191,332 224,227 Lecas-Nawrocka A. 326 Labinger J. A. 119 Leclerc G. 165 Lablache-Combier A. 277 Le Coq,A. 167 Labotka R. J. 382 Ledwith A. 212 Labrie F. 356 Lee A. O. 125 Ladas A. S. 11 Lee C. C. 58,222 Ladner J. E. 387 Lee C.-H.381 382 Laemmle J. T. 128 Lee C. Y. 423 Laila A. A. R. 184 Lee G. A. 266,319 Laine R. M. 102 Lee J. C. 393 Laing J. W. 85 382 Lee K. K. 56 LajSiC S. D. 410 41 1 Lee S. J. 97 11 1 Lajzerowin J. 9 Lee S. Y. C. 10 Lakings D. B. 389 Lee T. 423,425 Lakshmikantham M. V. 25 Lee T. S. 160 Lala A. K. 420 Leeman S. E. 353 La Mann G. 38 Lee-Ruff E. 216 Lambert G. 81 Lees R. G. 383 Lambert J. B. 122 288 Leete E. 399 413 Lamberton J. A. 414 Lefkowitz R. J. 424 Lamm B. 245 Le Goff M.-T. 166 225 Lammertsma K. 9 Legon S. 392 Lampert A. 422 Le Guen M. M. J. 210 Lan N. M. 94 Lehn J. M. 42 Landells R.G. M. 60 Lehr F. 124 Landfear S. N. 360 Lehr R. E. 52 Landheer C. A. 265 Leigh W. J. 92 Landy A. 393 Leiserowitz L.30 Lane C. F. 130,338 Leitich J. 46 253 Lange G. L. 310 LCJohn H. B.. 381 Langer U. 94 Lemaire S. 421 Langford G. E. 286 Lemal D. M.,47,203,280,282 Langlois N. 406 Le Men J. 406 Langridge R.,382 Lengfelder E. 369 371 Lantseva L. T. 230 Lennon J. 325 Lapkin I. I. 129 Lennox J. 153 Lapkoff C. B. 358 le Noble W. J. 56 Lapouyade R. 226 Lenz F. 169 Lappert M. F. 123 136 Leonard D. R.A. 210 Larcheveque M. 124 191 Leonard N. J. 379,380 195,332 Leonard-Coppens A. M. 307 Lardy H. A. 362 Lkonis J. 368 Larock R. C. 116 129 170 Leovey E. M. K. 9 Leroy G. 31 32 37 Larsen J. W. 101 Le Roy R. J. 80 Last J. A. 383 Leslie A. G. W. 384 Lathan W. A. 24 38 91 290 Lester T. E. 181 Lattes A. 248 Levek T. J. 177,297 Lau C.K. 282,336 Lever A. B. P.,216 Lau P.W. K. 135 Lever 0.W. 123,326 Laub R. J. 131 Levin C. C. 28 Laureni J. 92 Levin R. H. 86 Laurent E. 138 Levine R.,127 Lavelle F. 373 Levisalles J. 113 Leviston P. G. 288 Levit S. 368 Levitzki A. 424 Levy A. B. 131 Lewis F. D. 163 Lewis J. R. 268 Lexa D. 151 Ley S. V. 216 231 287 Li C. H. 349,356,421,422 Li M. P. 7 135 Liang G. 227 229 290 Liao C. C. 44 162 Liberek B. 9 Liberti A. 12 13 Libman J. 166 Liebman J. F. 27 91 Liebscher J. 254 269 Liedholm B. 214 Liehr J. G. 389 Lievin J. 34 Lightner D. A. 3 Lilienblum W. 96 Lill U. I. 365 Lim S. T. 93 Limbach H.-H. 205 Lin J. J. 324 Lin S. 393 Lindhoudt J. C. 169 Lindley J.M. 90 250 Lindley P. F. 50 Lindner H. J. 230 232 Lindstrom J. O. 249 Lindstrom J. 423 Lines R. 137 Ling N. 356 419 421 Linkowski G. E. 201 Linstrumelle G. 174 312 Liotta C. L. 35 Liotta D. C. 44 Liporskii A. A. 33 Lipscomb W. N. 33 34 69 360,362 Lipshutz B. H. 244 Liskow D. H. 23 Lissel M. 92 Litscher G. 151 Little R. D. 79 Litvinov V. P. 277 Liu B. 23 Liu K.-C. 165 Liu K.-T. 133 Liu L. F. 394 Liu M. T. H. 241 Lloyd G. J. 67 69 70 Lobach M. I. 104 Lobb R. R. 362 Lobl T. J. 233 Lochow C. F. 114 118 Lockwood M.,230 Lockyer G. D. jun. 67 Lodder G. 162 Lodge D. 427 Loenwengart G. 386 Loewen P.C. 392 444 Author Index Loh H. H. 356,421,422 Loie H.J. 357 Lomant A. J. 363 Lomas J. S. 202 Lombardo L. 237 Lombosi E. R. 12 Lombosi T. S. 12 Long M. 13 Longone D. T. 87 Loog E. P. 18 Loozen H. J. J. 284 Mpez A. F. 225 Lopez,L. 307 Lopp I. G. 128 Lorch E. A. 19 Lord J. A. H. 419 Lord R. C. 387 Lote C. J. 352 Lotts K. D. 93 Loud-Keast J. 222 Loudon G. M. 69 Louterman-Leloup G. 37 Loveitt M. E. 129 Lovelock J. E. 19 22 Lowe D. J. 370 Lowe J. A. 121 Lowe P. A. 362,365 Lowney L. 417 Lowry J. C. 395 Lu L. W. 389 Lubosch W. 124 Lucchese R. R. 38 Lucchini V.,59 169 Luche J.-L. 94 173 Ludlum D. B. 384 Lubbe F. 52,79 Luning B. 402 Luttke W. 30 Luhowy R. 220 Luisier J.-L. 128 Lukacs.G. 406 Lukas J. H. 184 Lukevits E. 275 Lumsden J. 364,369,372 Lund. H. 144 145 148 154 Lundstrom J. 402 Lunt E. 261 Luo T. 157 299 Luxon B. A. 29 Lwowski W. 90 Lynd R. A. 133,328 Lythgoe B. 304 Lyubchenko Y.L. 393 Ma T. S.. 11 McAdam M. E. 373 McAlister D. R. 101 MacAlpine G. A. 337 Macarovici R..252 McBrady J. J. 265 McBride J. M. 79 Maccagnani G. 44 McCapra F. 41 McCleery D. G. 313 McCloskey J. A. 388 389 McClung G. R. 182 McCollum G. J. 215 McCombs C. A. 45 183 McConkey F. W. 32 McCord J. M. 368,369 Mfiurt D. W. 385 McCreery J. H. 35 McCulloch R. K. 231 McCullough J. J. 164 243 McCurry P. M. 184 McDaniel R. S. jun. 96 280 MacDonald J.L. 15 21 McDonnell L. P.,160 McEntee M. F.,'63 Macfarlane R. D. 388 McGeoch D. 392 McGibboney R. G. 96,280 McGinnis J. 111 295 McGlone M. J. 211 McGuire S. E. 212 McGuire T. M. 45 Mach B. 393 McHale A. H. 390 Machleidt W.,358 McInnes A. G. 398 Mclntosh C. L. 121 McIntyre P. D. 211 McIver J. W. jun. 30 49 McKee D. B. 182 McKee R. 195,330 McKelvy J. F. 420 McKelvey J. M. 32 209 McKenna J. 188,288 McKenna J. M. 188,288 MacKenzie R. E. 112 McKenzie S. 181 McKeown M. C. 19 McKervey M. A. 286 McKillop A. 108 123 133 210,268,277 McLauchlan K. A. 77,81 McLean A. D. 26 McLennan D. J. 54,63 McMeeking J. 118,294 McMillan R. S. 100 McMullen G. L. 46 93 McMuK~ J.E. 308 McMurry T. B. H. 162 McNaught A. D. 277 McNaughton D. R. 381 McNeeley S. A. 155 McNeil E. A. 203 McNelis E. 216 Macomber R. S. 168,311 Maker C. C. 171,303 McPhail A. T. 130 McRobbie I. M. 90 250 252 Madani C. 16 Maddams W. F. 186 Madison V.,7 Madronero R. 255 Madsen N. B. 361 Maeda K. 107,258 Maeda Y.,372 Marki W. 358 Markl G. 135 136 Mageswaran S. 194 Ma& D. 46,274 Magnotta V. L. 172 Magnus P. D. 165 Magnussen S. 357 Mah T. 45 86 2 17 Mahajan J. R. 331 Mahmoud M. M. 50 Maier G. 228 291 Maillard B. 71 79 Maitlis P. M. 167 Mak A. S. 358 Maki Y.,379 Makino S. 412 Makisumi Y.,248 Makita M. 22 Makosza M. 123 Makrandi J. K. 92 Malcolm A.D. B. 361 362 364,365,366 Malherbe R. 47 Mallion R.B. 201 Malmstrom B. G. 369 Malpass D. B. 123 Mal'tsev A. K. 121 Mametsuka H. 216 Mandel G. S. 379 Mandel N. S. 379 Mandell L. 148 Maniatis T. 393 Manion M. L. 93 Manmade A. 93 Manning M. J. 125 142,215 Mannquez J. M. 101 Mao. D. T. 126 Mao S. W. 77 Marat K. 202 Marcati F. 100 Marchlewski L. 249 Marconi W. 100 Marcus F. 362 Marcus R. A. 77 Marcuui F. 59 169 Mareda J. 96 Mariaggi N. 378 Marians K. J. 393 Marin J. 67 Marino. G. 12 Marino J. P. 336 337 Marinovic N. 114 195 324 Marion L. 41 1 Marius W. 35 Markert J. 205 Markley J. L. 367 Markovitz A. 395 Marky M. 251 Marm. T. 369 Maroni P.275 Author Index Marquarding D. 349 Marron N. A. 159 Marshal J. L. 15 Marshall G. R.,350 351 Marten D. 115 Martens J. 267 Martial J. 365 Martigny P. 144 151 Martin D. R.,355 Martin J. C. 357 Martin R.,194 Martin S. F. 195 Martin W. B. jun. 219 Martynov B. I. 230 Masamune S. 228 234 291 332,347 Masamune T. 317 Maskill H. 233 Masler W. F. 99 100 Masse J. P. 313 Masson J. 128 Masson S. 169 Massuda D. 179,306 Masuda S. 203 Masuhara H. 82 Mataga N. 82 Matelin D. 21 Mathews R. G. 13 Mathey F. 25 Mathur S. S. 250 Math S. A. 279 Matlock P. L. 324 Mathsen F. A. 228 Matsuda Y.,262 Matsui H. 219 Matsui M. 319 Matsumoto K.. 277 Matsumoto S.113 Matsumura A. 117 Matsurnura S. 222 Matsuoka O. 37 Matsuoka Y. 117 Matsushima H. 316 Matsuura T. 216 222 Matthews C. R.,367 Matthews D. E. 20 Mauer W. 299 Maujean A. 246 Maurer H. 175 Mautner G. N. 370 Mavelli I. 371 Maxam A. M. 393,395 Maybury P. C. 110 Maycock A. L. 361 Mayeda E. A. 137 Mayer C. 363 Mayer E. 60 Mayers D. A. 194 Mayr H. 51,58 169 Mazanti G. 44 Mazenod F. 204 Mazur S. 85 Mazzeo P. 202 Mazzochi P. H. 157 Mazzu A. 44,240 Meadows J. H. 24 Mecca T. G. 55 Medina D. 389 Meguro H. 7 Mehta J. R.,384 Meier H. 244 Meinwald J. 157 245 Meinzer A. L. 287 Meisel D. 77 Meissner U. E. 235 Melega W. P. 206 227 Melia R.A.288 Melloni G. 59 169 Mellor N. 17 Meng P. C. jun. 66 Menke K. 219 Menzies I. D. 165 Merck A. 103 Merregaert J. 375 Merrifield R. B. 349 351 Merritt V. Y. 326 Mtszaros S. 12 Meth-Cohn O. 90 250 252. 276 Metzner P. 128 Meyer A. 115 Meyer W. 380 Meyers A. I. 123 191 193 242,276,316,327,334,338 Meyers C. 343 Meyers T. C. 382 Michel C. 369 Michel M. A. 151 Michelot D. 174 312 Michelson A. M. 373 Michl J. 235 Michniewin J. J. 390 Midura W. 180 304 Mihelich E. D. 123 276 338 Mikes F. 226 Mikhailov B. M. 133 Mikolajczyk M. 180,197,198 304 Milakofsky L. 62 Milburn P. W. 86 Mile B. 76 181 Miledi R.,423 Miles H. T. 384 Miles M. F. 176 Miles S.J. 136 Miller A. A. 420 Miller B. 221 Miller J. A. 199 Miller J. M. 11 317 Miller L. L. 139 141 143 153,219,400 Miller R.C. 164,243 392 Miller R.D. 326 336 Miller R.G. 114 118 Mills D. J. 209 Milone L. 110 Milstien S. 68 Mimura M. 263 Minachev Kh. M. 178 Minami N. 191,323 Minamoto K. 392 Mincuzzi A. 307 Min Jon W. 375,383,390 Minov V. M. 213 Minta A. 399 Minter D. E. 177 Mise T. 99 Mislow K. 122 Mison P. 224 Misra H. P. 369 372 Misra R.N. 325 Misudo T. 332 Misurni S. 218,219 Mitachi S. 99 Mitani M. 89 153 Mitchell A. R.,349 Mitchell G. J. 366 Mitchell M. A. 116 Mitchell R. E. 352 Mitchell R.H. 218 220 Mitchell R.W. 110 Mitsudo T.119 Mitsunobu O. 193 331 Mittal R.S.D. 194 Mitter L. 21 Miura I. 385 Miwa T. 50 Miyakoshi S. 232 284 Miyashita M. 325 Miyaura N. 131 332 Miyazaki H. 236 Miyazaki M. 234 Mizoroki T. 101 Mizuno H. 387 Mizuno M. 269 Mizuuchi K. 394 Mnatsakanyan V. A. 399 Mocella M. T. 112 Modro A. 169 Modro T. A. 209,210 Moffat A. C. 13 Moffat J. B. 38 Moffatt J. G. 380 Moffitt W. 3 Mohrnand S. 198 Mole L. E. 358 Molemans F. 375 Molinoff P. 423 Mollendal H. 38 Mollere P. D. 186 Molter M. 195 Momii R.K. 29 Monaco H. L. 360 Mondavi B. 371 Moniot J. L. 404 Monteil R.L. 50 Moodie R. B. 209,210 Moody C. J. 50 Moore D. R.,195 Moore G. A. 342,346 Moore H. W.189,244 Moore L. L. 260 446 Moore P. D. 386 Moore S. 368 ,Moran T. A. 304 Morand P. 101 196 329 Mordue W. 354 More K. M. 268 Moreau J.-L. 173 Moresw A. 230 Moretti I. 9 Morgan B. A. 355 418 419. 420 Morgan S. L. 12 Morgan T. 143 Mori A. 216 Mori M. 107 243 248 Morikawa A. 319 Morin O. 356 Morino Y. 361 Morio K. 228 234 291 Moritani I. 212 258 Moritsugu K. 158 Moriwaki M. 187 Moriyama M. 10 Morokuma K. 33,34,38,188 Morpurgo L. 371 Morrice A. G. 379 Morris D. G. 279 Morris E. R. 6 Morris H. R. 354 355 357 418 Morrison H. 156 Morrison J. D. 99 100 Morrow C. J. 100 Mortimer R. 179 308 Morton T. H. 186 Moschel R. C. 380 Moscowitz A.3 Moss G. P. 148 Moss R. A. 44,96 Moss W. K. A. 208 Motell E. L. 35 Motoyama T. 96 Mottweiler R. 103 Motz V. W. 97 112 Moult J. 361 Mouwing H. A. 247 Mrochek J. E. 389 Mruzik M. 36 Mudry W. L. 123 Muller C. 25 Mueller R. H. 132 190 Mullner H. 363 Miindrich R. 204 Muetterties E. L. 109 110 112 Muggleton B. 136 Mugnoli A. 235 Muhs W. H. 380 Muhsin M. 62 Mukai T. 230 Mukaiyarna T. 253 260 319 323,331 Muller N. 337 Mulliken R. S. 32 76 Munchausen L. L.,32,41,293 Mura A. J. 335 Murahashi. S. 308 Murahashi,S.-I. 107 131 180 258,314 Murai A. 3 17 Murakami S. 380 Murao K. 388 389 Murata I. 272 274 Murdock T. O. 128 Murphy D. 216 Murphy R.132 183,281 Murray C. D. 86 Murray N. 361 Murray R. W. 153 181 Muschik G. M. 13 Muskiet F. 367 Musso H. 94 Musso R. 394 Muszkat K. A. 267 Muthukumaraswamy N. 343 Mutin R. 97 114 Myall C. J. 140 Mychajlowskij W. 179 306 Mysov E. I. 230 Nader R. 219 Nagai T. 90 Nagai U. 8 Nagakura I. 282 284 336 337 Nagase H. 189,316 Nagata C. 366 Nagel A. 265 Nagpal D. K. 224 Nahorski S. R. 425 Naik N. C. 8 Naik V. R. 369 Nair B. M. 22 Naka M.,279 Nakadaira Y. 122 Nakagawa M. 235 236 237 285 Nakagima Y.,331 Nakajima T. 328 352 Nakajirna Y.,193 Nakaminami G. 235,285 Nakamura E. 134 Nakamura H. 323 Nakamura M. 215 Nakamura R. 113 Nakanishi K. 7 Nakanishi S.232 284 385 386,388 Nakata F. 92 173 Nakatsuji S. 236 235 285 Nakayama M. 24 Nakazaki M. 248 Nakazawa T. 230 Nakhshunov V. S. 178 Nalbandyan R. M. 369 Author Index Naleway C. A. 37 Nambuding M. E. M. 304 Naples J. O. 275 331 Narang S. A. 252 380 390 393 Narita M. 277 Nash H. A, 394 Nastasi M. 89 277 Nazer M. Z. 9 Neameyer J. L. 400 Nefedov 0.M. 121 Negishi,E. 130 132 133 170 308 Negishi E.-I. 118 31 1 Neidert E. 310 Neilan J. P. 102 Nelb R. G. jun. 224 Nelsen T. R. 245 Nelsestuen G. L. 357 Nelson G. L. 43 Nemoto H. 45 Neuberg M. K. 99 Neuman R. C. jun. 67 Neumann H. 126 Neumann S. M. 101 Neumeyer J. L. 146 Neurath H. 357 Neuss N.406 Newkirk D. D. 71 Newrnan M. S. 86,226 Newsom J. G. 88,255 Newton B. N. 214 Newton C. 392 Newton M. D. 36 Nguyen M.-T. 32 Nichols G. D. 27 Nicholson A. W. 69 Nicholson J. 22 Nickle J. H. 63 Nicolas G. 28 Nicolaus R. A. 253 Nicoletti R. 92 Nielsen S. O. 371 Niemeyer H. M. 33 Nierberl S. 245 Nierhaus K. H. 391 Niewstad Th.J. 184 Nilssen E. W. 24 33 Nilsson A. 143 Nimgirawath S. 326 Nimmo K. 65 Nirenberg M. 422 Nishida S. 218 Nishigaki S. 265 Nishigaki Y. 222 Nishiguchi T. 102 Nishihira M. 24 Nishikawa M. 263 Nishimura S. 246 388,389 Nishimura Y. 92 249 262 Nishinaga A. 64,216 Nishio O. 169 Nishizawa M. 114 195 324 Nitsch H. 46 Author Index Nitzche L.E. 25 Nivard R. J. F. 175 227 Noda H. 262 Node M.,317 Noels A. F. 96 113 118 N6gradi M.,210 Noguchi I. 153 Nojima M.,222 Nolte N. J. 9 Noltes J. G. 214 Nomoto T. 235 236 285 Nomura Y. 261 Nonaka T. 89 15 1 Norcross B. E. 31 1 Nordstrom B. 361 Norin T. 199 Noris. K. 393 Normant H. 124 191 195 Normant J. F. 179 Norris K. E. 383 Norstrom R. J. 92 Northrop F. 369 Nosikov V. V. 395 Nota G. 12 Notman H. 383 Novik J. 21 Novellino E. 253 Novikov J. N. 322 Noy E. 58,222 Noyori R. 293,412 Nozaki H. 135 167 170 178 179.305,306,311,315 Nozoe I. 207 Nu& L. 230 Numakunai T. 153 Numao N. 271 Numata T. 10 Nunn E. E. 87 Nunn F.A. 233 Nunn M.J. 199 Nussbaum A. L. 395 Nyberg K. 137,138,139,141 Nyborg J. 361 388 Nylund T. 156 Oae S. 10 Obayashi M.,178,306 Obendorf. S. K. 245 Oberlin R. 420 Obermeier R. 341 O’Brien R.D. 423 Ocasio I. 233 Oda J.. 187 Oda M.,232,234,284 Odaira Y.,104 Odea M.H. 394 O’Doherty C. M.,119 ertle K. 330 Osterberg R. 390 Ofstead E. A. 97 110 178 295 Ogata I. 101 105 Ogawa K. 264 Ogawa T. 319 Ogilvie K. K. 381 Ogura H. 7 Oguri T. 193,327 Ohashi M.,206 Ohashi Z. 388 Ohgishi H. 258 Ohkubo K. 28 Ohlsson I. 361 Ohnishi Y. 153 Ohno M. 92 173 Ohnuma Y. 186 Ohsawa A. 205,380 Ohsawa H. 269 Ohsawa S. 213 Ohshiro Y. 109 258 Ohta H. 313 Ohzeki K.12 Oien H. T. 265 Oikawa S. 25 1 Ojima I. 100 Ojima J. 235 285 Oka M.,58,222 Okada K. 167,311 Okada M.,28 Okamoto K. 231 Okamoto T. 139 235,285 Okamoto Y.,56 Okamura K. 406 Okano M.,169,210 Okawara M.,190,319 Okawara T. 260 Okayama K. 230 Oki M.,215 Okino H. 276 Okuhara K. 168 O’Kuhn S. 309 Okuno Y.,271 Olah G. A. 34,52,58,90,169 172,190,227,228,229,232 290,292,319,321 O’Leary M.H. 362 Olins A. L. 396 Oh D. E. 396 Oliver J. E. 185 OlliCro D. 274 Ollis W. D. 252 277 Olofson R. A. 43,93 Olsen R. J. 198 245 Olson D. R. 226 Omelanczuk J. 197 Omura K. 319 Onak T. 130 Ong B. S. 306 Ono M.,317 Onoe A. 169 Onuska F. I. 12 15 Oppolzer W.45.46 Orena M.,193 199 320 Orf H. W. 338 Orfanopoulos M. 303 Orger B. H. 166 Orvedal A. W. 201 Orville-Thomas W. J. 37 Osawa E. 286 Osborn J. A. 309 Osborne M. R. 385 Ose D. E. 372 Osella D. 110 Oshima K. 182 319 Otsubo T. 219 Otsuka A. S. 357 Otsuka S. 186 Ott W. 49 297 Ottersen T. 37 Ottnad C. 10 Ottnad M.,10 Oudet P. 396 Overman L. E. 45 183 319 Overton K. H. 410 Owens W. 266 Ozaki A. 101 Ozeki K. 379 Pabon H. J. J. 169 Pace N. R. 390 Pack G. R. 38 Paddock G. V. 393 Paddon-Row M.N. 43 208 230,233 Padwa A. 41 44 164 239 240,266,277 Page S. W.,410,411 Pagni R. M.,225 Paiaro G. 103 Pailer M.,13 Paillous N. 248 Pakkanen T.33 Pak-tsun Ho 410 Pal B. K. 417 Pal P. K. 362 Palensky F. 156 Palibroda N. 252 Palm P. 365 Palmer D. C. 264 Palmer G. E. 92 Palmer J. S. 424 Palmer L. 20 Palmieri P. 9 Palmquist U. 143 Pandolfi L. J. 110 Panet A. 392 Panteleev Y. A. 33 Panunzi A. 103 Panunzio M. 119 Pao Y.H. 3 Paoloni L. 38 Papendick H.-D. 16 Pappalardo G. 29 Paquette L. A. 44 52 139 156 157,206,227,231,232 233,287 448 Parayre E. R. 313 Parcher J. 13 Pardi L. 230 Pardue M. L. 394 Paredes S. 368 Parham W. E. 124 207 Park C. A. 253 Parker D. A, 15 Parker D. G. 172 190 Parker D. R. 122 Parker S. D. 161 Parker V. D. 142 143 Parr W. J. E. 202 Parton S. K. 261 Pasternak G.W. 418 Pasto D. J. 173,176,177,292 Paszye S. 378 Patchett A. A. 225 Patel D. J. 367 384 Paton R. M. 86 Patrick J. 423 Pattenden G. 156 196 279 304,308,317 Patterson J. M. 277 Patthy L. 362 Patzelova V. 12 Paul D. F. 223 Pauling H. 322 Pauliukonis L. T. 166 Paulsen H. 126 Pauly K.-H. 226 Pavlik J. W. 166 Pawliczek J.-B. 298 Peace B. W. 96,280 Peacock S. C. 276,328 Pearce A. 304 Pearce R. 123 Pearson A. J. 115 Pearson D. P. J. 94 254 Pearson H. 199 Pedersen E. B. 262 Pedersen J. B. 82 Pedersen L. D. 296 Pedersen L. G. 33 Pein J. 103 Pelizza F. 190 Pellacani L. 90 Pelletier S. W. 410 411 Pelter A. 130 131 168 311 338 Penczek S.190 Pendergast P. 34 Penn R. E. 198,245 Pennanen S. I. 254 Pensak D. A. 338 Pepperberg 1. M. 33 Percival A. 45 183 Pereyre M. 135 Perfetti R. B. 189 319 Perham R. N. 363 Perman J. 376 Perry D. H.,210 Perry R. P. 391 Person W. B. 76 Pert A. 420 422 Pert A. C. 420 Pert C. B. 417 418 422 Pert C. P. 420 Pesce G. 307 Peter H. 109 Peterson T. E. 357 Petrzilka M. 46 Petsko G. A. 361 Petty J. D. 262 Peyerimhoff S. D. 23 24 Pfenninger E. 45 Pfleiderer G. 363 Phillips D. C. 361 Phillips L. R. 282 Phisithkul S. 258 Photis J. M. 233 Pick M. 373 Piechucki C. 180 304 Piers E. 282 284 336 337 Pietra F. 230 231 Pietraszkiewicz,M. 182 Pietrzik E. 419 Pilati T.234 Pillsburg D. G. 304 Pines S. H. 212 Pinnick H. W. 214 Pino P. 105 Pioch J. 209 Pisano J. J. 353 Pitkethly R. C. 181 Pittman C. U. jun. 27 277 Pitts J. N. 301 Pitts W. 6 Pitzele B. S. 192,335 Piwinski J. J. 259 Place P. 3 11 Plachky M. 135 185 307 Plat M. 406 Platz M. S. 78 79 Pletcher D. 137 140 Plieninger H. 204 221 Plinke G. 275 Plucinska K. 9 Pochini A. 217 Pochinok V. Ya. 277 Podjarny A. 361 Pogson C. I. 361 Poindexter G. S. 155 Pojer P. M. 189 Poliakoff M. 253 Politzer J. R. 362 Politzer P. 27 91 Pollack R. M. 68 Pollak A. 182 Polonski T. 9 Polyanovsky 0.L. 395 Pomerantz M. 157 Ponaras A. A. 334 Poorker C. 194 Popkie H. E.29 Pople J. A. 24 25 26 27 28 34,37,91 127 290 291 Popov V. G. 103 Author Index Poppinger D. 32 Porter K. 383 Portmann R. 395 Posner G. H. 189 319 Postovskii I. Ya. 212 Potier A. 36 Potier P. 406 Potter C. J. 4% Potter L. T.,423 Potter S. E. 79 Potts J. T. jun. 359 Pouet M.-J. 213 Poupat C. 40? Povall T. J. 102 Powell G. P. 4 Power J. W. 357 358 Power P. P. 136 Poy F. 17 Praefcke K. 267 Prager R. H. 132 183,281 Prajer K. 9 Prakash G. K. S. 321 Pratt A. C. 158 Pratt J. C. 288 Preininger V. 399 Prensky W. 392 Prescott D. J. 351 Pressman D. 362 Prestidge R. L. 343 Preussmann R. 21 Pribnow D. 366 Price,P. A. 357,358 Prichard D. C. U. 425 Prickett J.E. 91 106 241 Pringle W. C. 287 Prinzbach H. 205 Probst E. 395 Proetzsch R. 257 Prokipcak J. M. 222 Pross A. 203 Prota G. 253 Proudfoot N. J. 392 Ptashne M. 395 Puget K. 373 Pullman A. 36 Purcell T. A. 331 Pusset J. 166 225 Quigley G. J. 387 Quin L. D. 288 Rabani J. 370 371,373 Rabbitts T. H. 393 Raber D. J. 62 3 13 Rabinovich D. 361 Rabinovitz M. 201 235 Radom L. 24 26 34 91 193 290 Raeymakers A. 375 Raft R. W. 32 Author Index Raftery M. A. 423 Ragan F. A. 260 Raghu S. 115 Rahman A. 318 Rainville D. P. 133 Raj Bhandary U. L. 388 392 Rakshit A. K. 35 192 Rarnachandran V. 400 Ramaekers J. J. M. 16. Ramage R. 342,345 346 Ramaiah M.46,261 Ramamoorthy B. 383 392 Ramamurthy V. 162 165 Raman N. 357,358 Ramljak Z. 21 Rampal J. B. 136 Ramsden C. A. 246,252,277 Rarnunni G. 41 Ranade A. C. 207 Rance M. J. 420 Randerath E. 390 Randerath K. 389,390 Randhawa H. S. 37 RandiC M. 223 Rando R. R. 362 Rao C. N. R. 37 Rao S. T. 387 Rao Y.S. 277 Rapaport E. 381 Raphael R. A. 311,331 337 Rapoport H. 85,338 Rapp K. M. 232 Rapp M. W. 62 Rappoport Z. 57,58 222 Rasched I. 362 Rasmus P. 198 Rasrnussen J. K. 164 240 Rasoanaivo P. 406 Rasshofer W. 276 Rastetter W. H. 272 Ratajnak H. 37 Ratier M. 135 Rau H. 227 Rauk A. 9 Raverdino V. 13 Ravindrath S. D. 372 Rayez J. C. 29 Raynolds P. W. 125,142,215 Rayss J.13 Reader G. W. 264 Reddy G. S. 60,227,291 Reed K. 423 Rees C. W. 50 243 Rees D. A. 6 Rees J. H. 2 11 Reese C. B. 94 175,284 Reetz M. T. 135 185 307 Regnier F. E. 14 Rehn D. 349 Rehn H. 349 Reich E. 423 Reichen W. 93 Reid B. R ,361 388 Reid G. L. 65 Reiffen M. 95 Reifling B. 170 Reimer K. J. 100 Reinecke M. G. 88 255 Reinhammar B. 369 Reisenauer H. P. 228 Reiser W. 232 Reiss J. A. 219 220 Reissenweber G. 272 Reiter F. 257 Relyea N. 362 Remion J. 178 307 Remold H. 363 Renken T. L. 245 Renner C. A, 204 205 Rettig M. F. 108 120 Reutrakul V. 258 Reverdy G. 95 Reynolds G. F. 76 Reynolds W. F. 203 Rheinhoudt D. N. 256 Rheinwald G.113 Ricard L. 275 Ricci A. 2 11 Rich A. 359 382 387 388 Rich D. H. 351 Richardson D. C. 361 369 370,372 Richardson F. S. 6 10 Richardson J. S. 361 369 370,372 Richardson R. S. 6 Richarz W. 232 Richey H. G. 296 Richter T. L. 284 Richkert R. C. 212 Ridd J. H. 209 2 11 Rieder R. 16 Rieder W. 223 Riedo F. 14 Riefling B. 129 Rieker A. 64 216 Riesner D. 390 Rigaud M. 16 Rigaudy J. 216 Riggs A. D. 393 Rigo A. 371 Rijks J. A. 12 15 Rindfleisch T. C. 20 Rio G. 326 Riordan J. F. 362 Ripoll J. L. 46 175 Riskulav R. 361 Ritchie E. 326 Ritchie G. L. D. 193 Rittner R. 261 Riveccie M. 146 Riviere M. 248 Rizvi S. Q. A. 203 Robben W. M. M. 284 Robbins J.D. 162 Roberts B. P. 74 136 207 Roberts D. C. 340 341 Roberts J. D. 195,202,224 Roberts P. B. 370 373 Roberts R. M. 212 Robertson H. D. 392 Robey R. L. 133 Robillard G. T. 388 Robins M. J. 380 Robinson P. J. 181 Robinson R. 416 Robinson S. R. 225 Rode B. M. 36 Roden K. 126 Rodehorst R. M. 164 Riiderer R. 210 Roos B. O. 37,38 Rosch K. 205 Roeterdink F. 263 Roger D. L. 8 Rogers M. E. 417 Rogers N. A. J. 161 Rogers T. 153 Rogerson C. V. 50 166 Rokach J. 264 Rold K. D. 182 Roller P. P. 385 Roloff A. 109 Romanowska K. 37 Rona R. J. 325 Ronlan A. 142 143 Rooney J. J. 112 Roques B. P. 420 Rosan A. 115 Rosenberg J. 393 Rosenberg J. L. 223 Rosenberg J.M. 382 Rosenberg M. 394 Rosenblom J. 402 Rosenblum M. 115 Rosenfeld M. N. 216 Rosenquist N. R. 229 Rosenthal I. 212 Ross J. A. 47 Ross S. D. 137 Rossei M. 28 Rossi A. R. 27 Rossi R. A. 225 Roswell D. F. 362 Roth H. D. 93 Roth W. R. 174 257 Rothchild R. 97 112 Rotilio G. 370 371 373 Rouessac R. 325 Rougeon F. 393 Roumestant M. L. 173,311 Roussi G. 166 225 Rovner R.,112 Rowbotham J. B. 202 Roy A. C. 418 Roychoudhury R. 394 Rozhkov I. N. 142 Rubin B. H. 361 Rubin J. 387 Rubin M. B. 47 160 Rubin R. J. 222 450 Author Index Ruchirawat S. 402 Rudler H. 113 Riiger W. 365 Ruelle P. 37 Runquist A. W. 189 319 Russchen F. 367 Russell P.J. 212 Russell R. A. 160 Ruston S. 304 Ruth J. L. 376 Rutledge P. S. 21 1 Rutten G. A. F. M. 15 Ruxer J. M.,274 Ryabtsev M.N. 349 Ryba M. 13 16 Rydon H. N. 340 Ryhage R. 20 Saatzev P. M. 24 Sabanski M. 132 Sabounji G. J. 261 Sabri S. S. 9 Sachdev H. S. 320 Sachdev K. 320 Sachs C. E. 333 Sadd J. S. 78,92 241 Saegusa T. 105 Saeman M. C. 11 1 Sanger H. L. 390 Sagar A. J. G. 168 Saidi M. R. 221 Saigo K. 319 331 Sainsbury M. 144 214 St.-Jacques M. 28,288 Saitkulova F.G. 129 Saito H. 231 379 Saitoh T. 365 Sakakibara T. 104 Sakata Y.,218 219 Sakodynskii K. I. 18 Sakuragi H. 208 Sakurai,H. 122,135,158,207 3 14 Salaun J. Y.,52 Salem L.41 156 301 Salomon M.,36 Salomon R. G. 206 266 Salomoni F. 13 Salser W. 393 Samain D. 312 Sammes P. G. 46 160 206 261,277,310,338 Samperi R. 12 13 Samuel C. J. 166 266 Sana M. 3 1,32 Sandall J. P. B. 208 Sanders E. B. 260 Sanders W. A. 27,91 Sanderson G. R. 6 Sandman C. A. 356 Sandri S. 193 199,320 Sands R. D. 184 San Filippo J. 327 Sangare M.,406 Sanger F. 394 Sankaran V. 226 Sanner R. D. 101 Santavy F. 399 Santiago C. 156 Santos R. 321 Santry D. P. 3 Santucci S. 230 Saram M. 369 371 Sarantakis D. 355 420 Sardella D. J. 254 Sarel S. 170 207 270 Sargent F. P. 78 Sarkanen S. 43 Sarma R. H. 381,382 Sarocchi M.-T. 367 Sasaki K. 409 Sasaki T.92 165 173,226 Sasaki Y.. 105 351 Satake T. 235 Sathe G. 383 Sato F. 120 Sato M. 120 231 Sato S. 120 372 Sato T. 100 191 219 323 382 Satoh S. 95 Sauer J. 272 Saunders A. D. 186 Saunders I. A. 420 Saunders M.,60 Saunders W. H. jun. 62 Saveant J. M. 151 Sawai H. 383 Sawyer D. T. 373 Saxton J. E. 406,411 Saya A. 361 Sayed Y. A. 207 Sayer T. S. B. 108,268 Sayrac T. 228,291 Scaiano J. C. 72 Scamehorn R. G. 213 Scandurra R. 362 Scarlata G. 29 Schaad L. J. 229 Schadt F. L. 55 Schaefer H. F. tert 23,24,34 35,38 Schafer R. 224 Schaefer T. 202 Schafer W. 25 Schifer-Ridder M. 225 242 267 Schafer H. 262 Schaffer S. W. 367 Schaflner K. 161 Schaffner W.395 Schalk D. E. 11 3 Schalke P. M. 378 Schally A. V.,356 Scharf H.-D. 47 160 Scharver J. D. 404 Scheffold,.R. 189 Scheinbaum M. L. 47 Scheinck E. 249 Scheiner S. 34 69 360 Scheinmann F. 168 Scheit K.H. 384 Scheraga H. A. 30 Schickaneder H. 271 Schiebel H. M.,382 Schlegel H. B. 122 287 Schlessinger R. H. 195 334 Schleyer P. von R. 24 26,27 28 34 55 59 62 127 232 286,290 Schlierf C. 228 Schiosser M. 43 127 Schmid G. H. 169 Schmid H. 274,397 Schmid M. F. 361 Schmidbaur H. 96 Schmidt A. 216 Schmidt P. 297 Schmidt R. 230 Schmidt U. 330 Schmierer R. 199 Schmitt G. 283 Schmitz H. 207 Schnabel I. 57 Schneider F. 397 Schneider G. R. 80 Schollkopf U.126 Schofield K. 209 210 Scholer F. R. 203 Scholfield C. N. 425 Schomburg G. 14 Schramm H. J. 364 Schreiber D. E. 36 Schrock R. R. 309 Schroder G. 275 Schroeder M.A. 101 Schroer W.-D. 230 Schuda P. F. 195,330 Schuit G. C. A. 172 Schulten H.-R. 382 Schulze U. 267 Schurig V. 119 Schuster D. I. 162 Schuster O. 227 Schuster P.,35 Schuster S. M.,362 Schut J. 252 Schwartz J. 119 120,325 Schwartz M. E. 177,292 Schwartz R. D. 13 Schwartz S. J. 131 Schwartzeman S. 316 Schweig A. 25 Schweingruber M. E. 391 Schwieger J. 256 Schwyzer R. 341 358 Scopes D. I. C. 189 Scopes P. M. 3 Scott L. T. 275 331 Scott W. 217 Author Index Scrocco E. 34 Sealy R.C.77 81 Secor H. V.,260 Sedat J. 394 Mat J. W. 394 Seebach D. 124,125,126,192 Seeger R.,27,28 127 Seeman J. I. 260 Seeman N. C. 382 Seeman P. 425 Seewald A. 346 Segal G. 30 41 Seghers L. 94 SCguin J. P.,25 Seiders R.P. 47 Seidl P. 12 Seifert M. 262 Seiter W. 281 Seitz E. P. 47 Sekiya A. 118 Sekiya T. 392 393 Selve C. 345 346 Semigran M. J. 282,308 Semmelhack C. L. 274 Semmelhack M. F. 330 Semple H. 361 Senga K. 265 Sentenac A. 366 367 Sep W., J. 8 Sepiol J. 281 Servi S. 330 Servin R.,138 141 Setton R.,214 bvGk J. 16 Sevrin M. 125 303 312 Seybold G. 229 Seyferth D. 129 134,243 Shaefer C. G. 320 Shafferman A. 374 Shamma M. 404 Shanshal M. 27 Sharma A. K. 319 Sharma R.A.376 Sharma S. K. 418 Sharp J. T. 50 86 271 Sharpless K. B. 182 315 319 Shatzmiller S. 152 Shaw A. 79,284,337 Shaw J. E. 214 Shcherbakova K. D. 12 Shea K. J. 204 Sheats. J. E. 60 Shechter H. 94,121,134,245 Sheepy J. M.,194 Shefter E. 42 290 Shein S. M. 214 Sheldrick W. S. 226 Shen C.-K. J. 394 Shen M. 161 Shepherd R.A. 298 Sheppard R.C. 345,351 Sherwin P.F. 198 245 Shevlin P. B. 35 Shibata T. 218 Shimada K. 212 Shimao I. 222 Shimizu I. 325 Shimo N. 107,258 Shine J. 393 Shiner V. J. jun. 62 Shingaki T. 90 Shinkai I. 260 268 277 Shinozaki H. 425 Shioiri T. 193 327 346 348 406 Shipman L. L. 30 Shippey M. A. 135 307 Shiroyama K. 45 Shishido K. 400 Shishido S. 210 Shizuri Y.409 Shkolina L. A. 17 Shmidel E. B. 17 18 Shoda S. 260 Shugar D. 384 Shull D. W. 296 Shults R.H. 173 Shutskever N. E. 361 Siebert W. 130 Siegel B. 21 1 Siegel M. W. 19 Sieker L. C. 361 Sigler G. F. 350 Sih C. J. 194 Silberg I. A. 252 Silberman L. 239 336 Silver E. H. 317 Silverton E. W. 370 Simanek V. 399 Simig G. 265 Simmons D. L. 41 1 Simon E. J. 417 Simon J. 15 Simon J. R.,425 Simon R.D. 358 Simonet J. 144,145,151,245 Simonetta M. 234 235 Simonnin M.-P. 2 13 Simonsen S. H. 261 Simantov R.,355,419,422 Simpson R. T. 396 Sims L. B. 188 Sinclair J. A. 130 168 311 Sindler-Kulyk M. 157 206 Sindona G. 177 Sing A. 189 244 Singer B. 378 Singer L. A. 74 Singer S. P.182 Singh H. 382 Singh R.K. 184,330 Singh R.P. 390 Singh S. P. 194 Sinn H. 103 Sinnwell V. 126 Sinou D. 101 114 Sioda R. E. 148 Sioumis A. A. 414 451 Siskin M.,172 Siu T.-W. 218 Siva Sanker D. V. 36 Sjoberg B. 390 Sjoberg K. 216 Sjoberg S. 6 Skaarup S. 23 28 186 Skalski B. 378 Skancke A. 24 Skanchke P. N. 186 Skarzewski J. 222 Sket B. 166 Skoglund M. 121 Skold C. N. 125 Skopenko V. N. 277 Skrowaczewska Z. 222 Slattery S. A. 399 Slocum D. W. 124 Sloof P. 391 Smallcombe S. H. 233 Smart B. E. 60,227,228,291 Smetanyuk V. I. 103 Smets F. 261 Smilansky A. 361 Smith A. B. 93 Smith C. D. 47 Smith C. F. C. 420 Smith C. Z. 140 Smith D. G. 398 Smith E. L. 362 Smith H. E.9 Smith J. G. 194 Smith K. 121 123 126 128 130,168,195,311,332 Smith L. C. 350 Smith L. J. 27 Smith M. 392 Smith M. R.,27 Smith R.G. 214 Smith R.L. 93 Smith R.N. M. 134 Smith T. W. 136 355,418 Smith-Palmer T. 21 1 Smolanoff J. 240 Smyth D. G. 356 357 419 420,421,422 Snell C. R.,356,357,419,420 421,422 Snider B. B. 184 Sninsky J. J. 383 Snopek T. J. 393 Snow R.A. 139 156 157 Snowden R.L. 304 Snyder J. J. 161 Snyder S. 417,418,424 Snyder S. H. 355 416 419 422,423,425,426,427 Sobczak R.L. 234 Soderberg B. O. 361 Siiderlund G. 361 Soll D. G. 388 Sogah G. D. Y.,190 Sogah Y.,328 Sogin M. L. 390 452 Sohar P. 268 Sojlk L. 12 Solan V. C. 378 solc A. 21 Solladii G.274 Solladit-Cavallo A. 274 Sollner-Webb B. 396 Solomennikova I. I. 275 Solouki B. 198 Soloway A. H. 317 Sommer L. H. 122 Sondheimer F. 202 233 234 237 Sonnet P. E. 185 Sonoda A. 107,131,180,258 308,314 Sonoda T. 156,222 248 Sonogashira K. 103 117 Sorensen T. S. 60 Sorriso S. 29 Sotowia A. J. 129 Sottrup-Jensen L. 357 Soulen R. L. 281 Soumillion J. P. 208 Soutar A. K. 350 Souto-Bachiller F. 332 347 Sow-mei Lai Chen 7 Spackman I. H. 63 Spangler C. W. 4 1,s 1 Spangler R. J. 282 Sparrow J. T. 350 Spear R. J. 290 Spears K. G. 36 Specker M.A. 379 Speltz L. M. 190 Spencer J. L. 103 Sperling J. 368 Spielvogel B. F. 130 Spottl R. 369 Sprague E. D. 80 Squires C. 391 Sridhar N. 222 Srinivasachar K.165 Srinivasan P. 268 Srivastava S. C. 216 Sriwidada J. 391 Staab H. A. 235 Stachowiak K. 9 Staemmler V. 23 Staicu S. 116 Staley S. W. 201 Stanovnik B. 277 Staral J. S. 52,228,232,290 Stark G. R. 363 Staunton J. 402 Stawinski J. 252,380 393 Steer M. J. 424 Stefani F. 29 Stefaniuk E.,50 271 Steffen E. K. 96,280 Stefik M. J. 20 Steglich W. 268,346 Stein A. 388 Stein G. 374 Stein L. 355 Steinbach K. 96 Steinberg H. 280 Steinman D. H. 192 335 Steinman H. M. 369 Steitz T. A. 361 Stekla J. 21 Stellman S. D. 382 Step G. 286 Stermitz F. R. 400 Stern R. L. 233 Sternbach H. 362 365 366 Stevens D. 86 Stevenson G. R. 233 Stewart A. 112 Still W. C. 135 317 Stille J.K. 101 104 224 Stirling C. J. M. 63 Stirling I. 195 St~gard,A. 23 29 Stohrer W.-D. 234 Stokes A. M. 362 Stolyarov B. V. 212 Stone F. G. A. 103 Stone J. V. 354 Stork G. 42 123 184 309 323,334 Stork P. J. 193 276 331 Storr R. C. 243 Stout C. D. 387 Strassburger P. 185 Strathdee R. S. 50 271 Straub H. 229 Strauss M. J. 264 Strausz 0.P. 31 92 Streck R. 113 Streith J. 89 277 Streitwieser A. jun. 32 59 209 Strelets B. K. 254 Strickland D. K. 182 Strickland R. W. 6 Strid L. 362 Strub H. 89 Struhl K. 395 Strunk U. 256 Strum G. M. 196 Strydom P. J. 52 Srusche D. 205 Su T. P. 422 Suares J. 414 Suan R. 162 Subrahmanyam C. 131 Subramanian E. 382 Subramanian L. R. 59 Subramanyam V.317 Suda M. 230 Suddath F. L. 382 Suehiro T. 208 Siimegi J. 367 Suss H. U. 232 Suggs J. W. 309,321 Sugiara S. 398 Sugihara Y. 228 272 291 Author Index Sugimoto K. 313 Sugimoto T. 45 Sugino A. 393 Sullivan A. B. 76 Sullivan D. F. 189 Sulsky R. B. 334 Sultanbawa M.U. S. 194 Summerville R. H. 38 Sun H. 122 Sund H. 362 363 Sundaralingam M. 387 Sundberg J. E. 213 Sung M.-L. 413 Sunko D. E. 26 Sures I. 395 Surpateanu G. 277 Suschitzky H. 90 188 248 250,252 Sussman J. L. 387 Sustmann R. 52 79 Suther D. J. 279 Suwa S. 206 Suzuki A. 131 137,332 Suzuki K.,351 367 372 Suzuki M.,379 Suzuki S. 263 323 Suzuki T. 156 222 358 Suzuki Y. 117 Svanholt K. L. 194 Swain C. G. 60 Swain M.L. 262 Swaminathan K. 123 126 195,332 Swanson S. B. 214 Swenton J. S. 125 142 163 2 15,263 Swern D. 319 Sygusch J. 361 Sylvestre-Panthet P. 329 Symonyan M. Y.,369 Szabo J. 268 Szczesniak M. M. 37 Szele I. 26 Szelke M. 352 Szepesy L. 15 Szymanski R. 190 Tabakovic I. 144 Tabata,M. 130,131,168,311 Taber D. F. 326 Tabusa F. 249 Tabushi I. 95 219 276 328 Tachibana H. 393 Tachibana S. 352 Tachikawa R. 249 Taft R. W. 203 Taguchi H. 377 Taguchi T. 169 Tait J. C. 76 Tajika M.,99 Takabe T. 27 Takacs E. C. 12 Author Index TakPcs J. M. 12 Takahashi M. 27,249 Takahashi M. A. 373 Takahashi S. 117 Takahashi Y. 137,261 Takaishi N. 101 Takajanagi H.,7 Takamuku S. 158 Takanami M.393 Takano S. 400 Takaya H. 293 Takeda S. 248,263 Takegami Y. 119,332 Takeshita H. 216 Taketo M. 365 Takenchi H. 89 Takeuchi K. 231 Takeuchi Y. 41,261,276 Takeya T. 392 Takken H. J. 322 Talberg H. J. 37 Talbot R. J. E. 64 Tallman J. H. 422 Tam P. S. 352 Tam T.-F. 218 Tam W. 120 Tamao K. 99 Tamura Y. 92 249 262,316 Tanabe Y. 204 Tanaka K. 229 Tanaka M. 101,105 Tanaka T. 260 Tanaka Y. 206,379 Tanase S. 361 Tani H. 186 Tanida G. 139 Taniguchi H. 156 222 248 Tanimoto S. 224 Tapia O. 361 Tardella P. A. 90 Tarjan G. 12 14 Tau C. E. 388 Tarrab-Hazdai R. 423 Tashiro M. 212 Tatsumi K. 32 Tatsuno T. 303 Tatsuoka T. 274 Taub D. 228 Taube H. 374 Tavernier D.277 Tayal S. R. 207 Taylor A. W. 337 Taylor E. C. 133,210 Taylor G. F. 45 183 Taylor J. F. 16 73 Taylor P. J. 16 Taylor R. 210 262 Taylor W. C. 326 Tedder J. M. 79 178 Tedesco J. 425 Tee 0.S. 43 Tenpas C. J. 33 Teoule R. 378 Terade A, 249 Teranishi S. 212 Terem B. 148 150 Terenius L. 417,418,422 Teschner M. 192 Tesser G. I. 340,341 Teutsch G. 341 Tewari R.S. 224 Teysseyre J. 31 Teyssit P. 96 113 118 241 Tezuka T. 52 Thal C. 406 Thalmann A. 330 Thea S. 226 ThBtaz C. 89,241 Thiagarajan V. 66 Thies W. 47 Thinh N. V. 96 280 Thom D. 6 Thomalla M. 138 Thomas E. J. 279 Thomas K. A. 361,369,370 Thomas K. M. 136 Thomas M. 390 Thomas M. G. 110 Thomas M. J. 159 Thomas P. J. 63 Thomas R.C. 132 239 308 336 Thome F. A. 20 Thompson D. J. 101 Thompson D. W. 119 Thompson N. J. 188 Thompson R. C. 340 Thompson R.H. 338 Thomson S. J. 181 Thornber C. W. 402 Throp W. D. 346 Thuillier,A. 169 Thulin B. 220 227 Thummel R. P. 207 Thyres M. 281 Thys F. 395 Ticozzi C. 274 Tiernay J. M. 21 Tinnemans A. H. A. 224 Tisler M. 277 Titani K. 357 Titus P. E. 222 Tobey S. W. 28 1 Toda F. 229 Toder B. H. 93 Togashi S. 307 Tohda Y. 103 Toi H. 131 314 Tokoroyama T. 320 Tokuda M. 137 169 Tokumaru K. 203,208 Tokura N. 222 Tokuyama T. 398 Tolman C. A. 102 Tomarchio L. 13 Tomasi J. 34 Tomasik P. 277 Tomer K. B. 226 Tominaga Y. 262 Tomita H. 15 Tomita K. 249 Tomita S.235,285 Toome V. 9 Topp W. C. 37 Topsom R. D. 203 Torgerson D. F. 388 Tori K. 203 Torii S. 139 Torimoto N. 90 Torre G. 9 Torrence P. F. 384 Torssell K. 255 Toshimitsu A. 210 T&h T. 12 Totty R. N. 4 Townsend L. B. 379 Townshend R. E. 28,41,186 Traas P. C. 322 Traber R. P. 213 Tranquilla T. 383 Traub W. 361 Travers A. 365 Traynham J. G. 208 Traynor S. G. 233 Tremper A. 164,240 Trenbeath S. L. 133 Trethewey K. R. 164 Tribout M. 368 Trifunac, A. D. 82 Trinajstic N. 223 Trkovnik M. 144 Trommer W. E. 363 Trompenaars W. P.,256 Trost B. M. 45 117 123 183 201,282,326,336 Troxler E. 109 Troxler F. 424 True N. S. 193 Truesdale E. A. 159 218 Truesdale L. K. 182 Trybulski E.J. 321 Tsai C.-H. 219 Tsai C. S. J. 410 Tsai T. Y. R. 410 Tse M.-W. 136 Tseng L. F. 356,421,422 Tseng S.-S. 160 Tsubomura H. 82 Tsuchida T. 89 Tsuchimoto M. 246 Tsuchiya T. 264 Tsuda M. 251 Tsuda T. 105 Tsui F. P. 89 270 Tsuji J. 325 Tsuji M. 50 Tsuji S. 367 Tsuji T. 218 Tsujimoto K. 206 Tsunetsuga J. 23 1 Tsurumi H. 263 Tsutsui M. 260 Tu C.-P. D. 383 Tuck D. G. 320 Tuinstra H. E. 11 1 Tully C. R. 122 257 Tumey. M L. 121 Tunaley D. 134 Tunemoto D. 326 Turchi I. J. 25 Turner J. J. 253 Turner S. 338 Turro,N. J. 160,165,204,205 Tuval M. 30 Tuimwa K.,7 Tweedy H. E. 119 Uaprasert V. 182 Uccella N. 177 Uchida K. 135 170 179 305 Uchida T. 277 Uchiyama M.352 379 Uemura S. 169 210 Ueno Y. 190,319 Uenoyama K. 398 ugi I. 344,349 Uliana J. 285 Ullman E. F. 160 Ulmen J. 289 298 Ulrich P. 189 316 330 Ulrich W. R. 49 Umani-Ronchi A. 119 324 Umemoto T. 219 Umeyama H. 33,38,188 Umezu M. 222 Umino N. 318 Ungaro R. 217 Ungemach S. R. 23 Urban R. 349 Urzan R. 25 Usbeck E. 363 Usher D. A. 390 Usieli V. 170 207 Usui M. 331 Utimoto K. 135 167 170 178 179,305,306,3 1 1 Utley J. H. P. 137 138 147 148 150. 154 Uyegaki. M. 272 Vaciago A. 202 Vagelos P. R. 351 Vaglio G. A. 110 Vaish S. 192 ValachoviEovi M. 15 Valentine J. S. 327 Valenzuela P. 365 Valle M.,110 van Bekkum H. 51 184,299 van den Berg A. 367 Van Den Berg J. H. M. 16 Van den Berghe A.375 Van den Broek P. 397 van den Hende-Timmer L. 367 van der Gem A. 189 van der Kerk G. J. M. 122 van der Kerk S. M. 122 van der Linden J. 184 van der Plas H. C. 263,265 van de Sande J. H. 392 Van de Voorde A. 395 Vandlen R. 423 Van Duuren B. L. 386 Van Ende D. 125,303,316 Van Horn D. E. 133,170,308 van Koten G. 214 Van Leusen A. M. 247,252 van Mourik G. L. 169 Van Oeveen D. 13 van Rantwijk F. 51 299 Van Ree J. M. 422 Van Rheenen V. 3 15 van Rossum A. J. G. 175 van Veldhuizen A. 265 Vgradi A. 12 Varga I. 268 Varga K. 20 Varshavsky A. J. 396 Vasudevan K. 23 Vaziri C. 28,288 Vecchia L. D. 125 Vedejs E. 298 Vehar G. A. 362 Venegas A. 365 Venetianer P. 367 Verachtert H. 13 Veracini C.A. 230 Verga G. R. 17 Verhaegen G. 34 Verheyden J. P. H. 380 Verhoeren J. W. 8 Verhoeven T. R. 11 7 Verma N. C. 81.82 Vernon J. M. 87 Vessiere R. 241 Vialle J. 128 Vibert A. 128 Vick S. C. 134 243 Victor R. 170 207 Vidal S.,208 Viehe H. G. 261 Vierhapper F. W. 223 Vigevani A. 44 Viglino P. 371 Vigneron J. P. 192 Villafranca J. J. 373 Villemin D. 113 Villieras J. 179 Vining L. C. 398 Viskocil J. F. 289 Vitagliano A. 103 Vizard D. L. 393 Vlasov V. M. 206 Vlattas I. 125 Author Index Voelter W. 419 Vogel E. 224 225 235 242 267 Vogel T. M. 89 270 Vogel Z.,423 Vogler H. 235 Vogtle F. 49 276 Vohra K. N. 195 Voight E. 244 Volckaert G. 375 390 Vollhardt K. P. C.,45,86 102 171,207,224,226,277,284 Vollmer H.-J.103 Volnava T. V. 361 Vologodskii A. V. 393 Volosov A. P.,7 Vol'pin M. E. 322 Von Rappard E. 21 Vorbriiggen H. 377 Vorona E. N. 18 Vosman F. 388 Vrieze K. 127 Vunnam R. R. 343 Vyas H. M. 82 83 Waalkes T. P. 389 Wachter E. 358 Wada A. 393 Waddell W. H. 204 Wade L. E. 49 Wade P. A. 204,214 Wagner H.-U. 229 Wagner P. J. 159 161 Wagner W. R. 11 1 Wagner-Jauregg T. 41,277 Wagnihre G. H. 7 Waheed N. 208,318 Wahl A. 28 Wahl G. H.; jun. 60 Wahlstrom A. 418,422 Wahren R. 324 Wakatsuki Y.,106,259 Waksmundzki A. 13 Waley S. G. 361 Walker B. J. 86 Walker J. A. 132 308 356 Walker R. T. 376 Wall R. 393 Wallace T. W. 96 Walley A. R. 188 Wallis T.G. 44 Walser A. 250 Walsh K. A. 357 Walter B. 368 Walter J. A. 398 Walton D. R. M. 134 215 Walton J. C. 79 178 Wan C. N. 325 Wan J. K. S. 82 83 Wang D. 368 Wang H.-C. 213 Author Index Wang J. C. 394 Wang S. Y.,377,378 Ward R. C. 371 Ward S. E. 224 Ware W. R. 162 Warin R.,96 241 Waring L. C. 188 Warner R. C. 366 Warren S. 126 180 199,304 326 Warren S. G. 360 Warrener R. N. 43 160 208 230,233 Wasielewski M. R. 65 Wasik S. 13 Wasserman A. R. 24 Wasserman E. 24 91 290 Wasserman H. H. 165 244 28 1 Wasserman Z. R.,91 290 Wasylyk B. 366 Wat C.-K. 398 Watanabe C. 15 Watanabe K. A. 376 Watanabe Y.,119 260 332 Waterfield A. A. 355 419 421 Waterhouse A. 173 Waterman E.L. 107,216,248 Waters D. L. 47 Watkins B. F. 141 Watrin K. G. 357 Watson C. R.,jun. 225 Watson S. C. 123 Watson W. D. 21 1 Watt D. S. 332 Watt R. A. 46 261 268 310 Waysman C. 2 1 Weatherhead R. H. 42 194 Weathers P. 358 Webb B. C. 225 Webb G. 181 Webb H. M. 33,35 Webb J. G. K. 214 Weber E. 276 Weber H. P. 45 Weber J. 26 Webster B. 36 Weedon B. C. L. 137 148 Weeke F. 14 Wege D. 231 Wegner G. 42 Wehner W. 276 Wei E. 356 422 Weigang 0.E. 3 Weigel L. O. 9 320 Weigele M. 9 Weill-Raynal J. 130 167 Weiner M. 47 160 Weinges K. 204 Weinstein B. 259 352 357 Weinstein I. B. 385 386 Weisgraberr K. A. 153 Weiss D. S. 158 Weiss J. 374 Weiss L. B. 207 Weiss R.,228 Weisshuhn M.C. 255 Weisz A. 226 Welch J. 321 Wellard N. K. 311 Weller A. 165 Welling G. W. 367 Wells C. H. J. 225 Welsher T. L. 228 Wernpen I. 376 Wernple J. 194 Wender P. A. 337 Wendling L. A. 240 Wendolowski J. J. 186 Wenkert E. 406 Wennerbeck I. 138 Wennerstrom H. 37 38 Wennerstrom O. 220 227 Wenska G. 378 Wentrup C. 89,9 1,93,94,24 1 Wepster B. M. 203 Weser U.,369 371 373,374 Wessely V.,205 West C. T. 72 171 303 West D. E. 214 West R. 218 281 West S. D. 12 Westhof E. 31 Westmoreland D. G. 367 Weston J. B. 210 Wetlaufer D. B. 367 Wetmore S. I. jun. 44 240 Wetter H. F. 99 Wetzels M. L. 16 Wexler A. 163. 263 Wheaton G. A. 93 White D. N. J. 30 White E. H. 56 233 362 White H.S. 223 White J. F. 133 White R.L. 390 White W. N. 223 Whiting D. A. 323 Whiting M. C. 56 Whitlock H. W. jun. 338 Whitlock J. P. jun. 396 Whitten C. E. 327 Whitten J. L. 33 Whittle P. J. 243 Whytock D. A. 81 Wiberg K. B. 28 186 205 Widdowson D. A. 405 Widiger G. N. 398 Wienorek H. 190 Wiegand G. 380 Wiesemann T. L. 128 Wiesner K. 410,411 Wife R.L. 217 Wiger G. R. 108 Wight F. R.,228 Wightrnan R. H. 237 Wilcox C. F. jun. 26 69 Wild H. J. 337 Wilde H. 261 Wildeman J. 247 Wiley D. C. 360 Wiley P. F. 55 Wilka E.-M. 125 Wilkinson G. 64 Willard A. K.,190 Williams D. L. H. 223 Williams D. R.,191 334 Williams F. 80 Williams G. H. 208 Williams G. R.J. 24 Williams L. T. 424 Williams R.J.P. 355 Williamson K. L. 195 Willison M. J. 213 225 Willner I. 201 Wilson G. 368 Wilson H. A. 418 Wilson H. R. 382 Wilson I. A. 361 Wilson J. M. 52 Wilson J. W. 313 Wilson K. J. 354 Wilson M. A. 18 Wilson M. L. 402 Wilson R. S. 417 Wilson S. E. 183,309 Wilson S. R.,113 126,282 Winans R.E. 69 Winkler J. 309 Winter B. 161 Winter J. N. 136 Wipff G. 42 Wise C. D. 355 420 Wisloff-Nilssen E. 38 Wistrand L. G. 141 Withers G. P. 325 Witkop B. 384 398 Witteveen J. G. 338 Wittman H. G. 391 Wndoloski J. J. 28 Woessner W. D. 328 Wohlleben W. 250 Wojnowich L. 130 Wold F. 368 Wolf H. R. 158 Wolf J. F. 32 Wolf J. G. 275 Wolfe S. 122 287 Wolfenden R. 361 Wolff,S. 158 159 Wolstencroft J.H. 352 Wolters E. Th.M. 341 Wong H. N. C. 202,233,234 Wong K. 425 Wong K. L. 388 Wong P.-C. 218 Woo K.W. 192,413 Wood D. E. 27 Wood K. O. 393 Woodard C. J. 424 Woodby E. S. 210 456 Woodgate P. D.. 21 I Woodward C. 367 Woodward R.B. 3 Worley S. D. 35 Wormann H. 96 Woznick M. 265. Wright E. B. 396 Wright J. L. C. 398 Wrighton M. S. 101 WU C.-W. 363 365 Wu E. S. C. 330 WU,F. Y.-H. 363,365 Wu M. 395 Wu M. T. 228 Wu R.,383,393,394 Wu Shing K. 27 WU W.-S. 164 243 Wulfman D. S. 96 280 Wunderer G. 358 Wunk T. A. 172 Wyatt J. 144 214 Wydler C. 219 Wynberg H. 9 255 Yak A. 90,251 Yabuki S. 393 Yabuki Y. 167,3 11 Yabushita Y. 328 Yagi H. 153,385 Yahner J.A. 263 Yakamura F. 372 Yakobson G. G. 206 Yamada K. 189,316,409 Yamada S.-I. 128 191 193 206,318,325,327,346,348 406 Yamaguchi K. 32 Yamaguchi R. 294 Yamakawa M. 293 Yamamori T. 262 Yamamoto H. 315 Yamamoto J. 222 Yamamoto K. 99 248,325 Yamamoto S. 22 Yamamoto Y. 107 131 180 187,308,314 Yamamura H. I. 423 Yamamura S. 424 Yamashiro D. 42 1 Yamashita A. 169 Yamashita J. 210 Yamashita M. 119 332 Yamashita O. 165 226 Yamashita S. 279 Yamazake H. 175 Yamazaki H. 106 107 259 300 Yanai M. 263 Yanami T. 325 Yang C. C. 349 Yang L. S. 134,245 Yang N. C. 164,165,243 Yang S. K. 385 Yanofsky C. 391 Yarbrough L. R.,363 365 Yarwood A. J. 156,301 Yasuda A. 315 Yasuda H. 186 Yasuda K.231 Yasuhara T. 352 Yasuoka N. 274 Yatagai H. 180 308 Yates G. B. 138 Yates K. 24 43 169 210 Yates P. 45 Yates R. L. 25,32,33,43,201 Yavari I. 289 Yeh H. J. C. 386 Yin-Kuen Lam 410 Yogev A. 49 155,280 Yokomachi T. 235 Yokoyama Y. 346,348 Yonath A. 361 Yoneda N. 172 190 Yonemitsu O. 271 Yoon N. M. 314 Yoshida H. 76 353 Yoshida M. 203 208 262 Yoshida Z. 95 Yoshida Z.-I. 219 Yoshifuji S. 401 Yoshikawa K. 372 Yoshikoshi A. 325 Yoshimine M. 26,37 Yoshimura T. 10 Yoshimura Y. 203 Yoshioka T. 229 Yost F. J. 373 Younes M. 374 Author Index Young A. 424 Young A. B. 426,427 Young G. T. 342,343 Young G. W. 20 Young M. A. 382 Young P. E. 7 Young R.N. 64,287 Younkin J. M. 27 Yovell J.270 Ysebaert M. 375,395 Yuh Y. 289 Yui M. 406 Za’ater M. F. 9 Zahradnik R. 30 Zak H.,330 Zaldivar J.,%5 Zamecnik P. C. 381 Zass E. 128 Zatorski A. 180 304 Zdansky G. 10 Zecchi G. 44 Zehnbauer B. 395 Zeid I. 253 Zelchan G. I. 275 Zeman I. 21 Zenchoff G. S. 250 Zeppezauer E. 361 Zhuze A. L. 395 Ziegler F. E. 215 Ziegler J. C. 190 345 Zielinski W. L. jun. 13 Ziff E. B. 394 Zillig W. 365 Zimmerman H.-J. 131 Zimmermann I. 219 Zoccolillo L. 13 Zollinger H. 60 Zon G. 89 270 Zsindely J. 274 Zubkov V. A. 7. Zukin S. R.,427 Zupan M.,166 169 182 Zurek G. 365 Zweifel G. 133 328 Zwinkels J. C. M. 220 Zytkovin T. H. 357

ISSN:0069-3030    

DOI:10.1039/OC9767300430

出版商:RSC    

年代:1976

数据来源: RSC