摘要:

AbstractOptically pure isotopically labeled phenprocoumon was prepared from resolved phenprocoumon via ring opening and decarboxylation followed by recarboxylation with suitably labeled (13C,14C) diethyl carbonate and ring closure. A similar procedure was followed for the preparation of optically pure isotopically labeled warfarin after protection of the side chain carbonyl group by formation of an ethylene dithioketal derivative. The protecting group was quantitatively removed after incorporation of label by treatment with mercuric acetate.

ISSN:0362-4803    

DOI:10.1002/jlcr.2580170602

出版商:John Wiley&Sons, Ltd.    

年代:1980

数据来源: WILEY

摘要:

Abstract[2‐14C]1,3,7,9‐, 0(2),1,7,9‐ and 0(8),1,3,7‐Tetramethyluric acid were prepared by methylation of [2‐14C]uric acid with dimethyl sulfate at pH 9. The yield after repeated (3x) purification by TLC was 44.9%, 4.4% and 6.3% res

ISSN:0362-4803    

DOI:10.1002/jlcr.2580170603

出版商:John Wiley&Sons, Ltd.    

年代:1980

数据来源: WILEY

摘要:

AbstractStearic, palmitic, myristic and lauric acids have been labelled with tritium in the alpha carbon position, and the position of the label confirmed using tritium N.M.R. spectrometry. The α‐3H acids were prepared using tritiated water with sulphuric acid or sodium hydroxide as catalysts. Specifically labelled compounds of high specific activity and radiochemical purity were obtain

ISSN:0362-4803    

DOI:10.1002/jlcr.2580170604

出版商:John Wiley&Sons, Ltd.    

年代:1980

数据来源: WILEY

摘要:

AbstractThe preparation of DL‐erythro‐2‐(4‐benzylpiperidino)‐1‐(4‐hydroxy‐phenyl)‐[1‐14C]propan‐1‐ol L‐(+)‐tartrate, Ifenprodil tartrate (Vadilex ®) from barium [14C]carbonate is described. The product was obtained in 29.2 % radiochemical yield and at a specifie activity of 47.6 mCi/mmol. This was diluted to 2 and 1 mCi/mmol for metabolism and distribution studies in man. The radiochemical purity of the d

ISSN:0362-4803    

DOI:10.1002/jlcr.2580170605

出版商:John Wiley&Sons, Ltd.    

年代:1980

数据来源: WILEY

摘要:

AbstractDL‐[2‐14C]Octan‐2‐sulPhate was prepared by sulphating DL‐[2‐14C]octan‐2‐ol with pyridine‐SO3adduct. Synthesis of the DL‐[2‐14C]alkanol started with carboxylation of hexyl magnesium bromide with14CO2. Subsequent methylation with diazomethane and reduction of the ester with lithium aluminium hydride Yieled [1‐14C]heptan‐1‐ol. The latter was oxidized to 1‐14C heptanal with Seloxcette. The [1‐14C]heptanal was reacted with methyl magnesium iodide to give DL‐[2‐14C]octan‐2‐ol. D(+)‐ and L(−)‐Octan‐2‐[35S]sulphate were synthesized by sulphating the stereochemically pure alcohols with pyridine‐35SO3prepared from35SO3. These synthetic routes provided specifically radiolabelled secondary alkyl sulphates of high chemical and radiochemical purity. The identity and purity of the products was confirmed by mass spectrometry, infrared spectro

ISSN:0362-4803    

DOI:10.1002/jlcr.2580170606

出版商:John Wiley&Sons, Ltd.    

年代:1980

数据来源: WILEY

摘要:

AbstractS‐Benzyl‐DL‐[1‐13C]cysteine was prepared from Na13CN by a three step synthesis and converted to the t‐butyloxycarbonyl derivative which was suitable for use in peptide synthesis. This compound was incorporated into the 1 and 6 positions of a variety of oxytocin and [8‐arginine]vasopressin derivatives and analogues via total synthesis using the solid phase method. The compounds were separated and purified by partition chromatography on Sephadex and their purity was checked by high pressure liquid chromatography. The compounds synthesized include [1‐hemi‐[1‐13C]cystine]oxytocin, [1‐hemi‐D‐[1‐13C]‐cystine]oxytocin, [1‐hemi‐[1‐13C]cystine, 8‐arginine]vasopressin, [1‐hemi‐D[1‐13C]cystine, 8‐arginine]vasopressin, [6‐hemi‐[1‐13C]cystine]oxytocin, [6‐hemi‐D‐[1‐13C]cystine]oxytocin, [1‐hemi‐D‐[1‐13C]cystine, 3‐D

ISSN:0362-4803    

DOI:10.1002/jlcr.2580170607

出版商:John Wiley&Sons, Ltd.    

年代:1980

数据来源: WILEY

摘要:

AbstractStarting from sodium acetate‐1‐13Cor ‐2‐13Cimproved procedures for the preparation of ethyl acetoacetate‐2,4‐13C2, ethyl acetoacetate‐1,3‐13C2, ethyl acetoacetate‐2‐13C, and ethyl acetoacetate‐2,3‐13C2are described. A method was also worked out which allows, using the labelled ethyl acetoacetates, to obtain Knorr's pyrrole (diethyl3,5‐dimethyl pyrrole‐2,4‐dicarboxylate) carrying the label in well‐defined positions in excellent yields. An example is given of further tr

ISSN:0362-4803    

DOI:10.1002/jlcr.2580170608

出版商:John Wiley&Sons, Ltd.    

年代:1980

数据来源: WILEY

摘要:

AbstractRPCNU was labelled with14C on three positions:‐ On the carboxyl of the acetyl groups‐ On the carboxyl of the acetyl groups‐ On the urea ca

ISSN:0362-4803    

DOI:10.1002/jlcr.2580170609

出版商:John Wiley&Sons, Ltd.    

年代:1980

数据来源: WILEY

摘要:

AbstractSYNTHESIS OF 2‐METHYL‐4,6 DINITRO PHENOL (RING U‐14C) (DNOC, DINOCringU‐14C)O‐methoxymethylphenol (ring U‐14C)3Was prepared in 82 % yieltd from phenol (ring U‐14C) and methylal in presence of p‐toluene sulfonic acid and molecular sieve. Ortholithiation of3with n Buli + TMEDA in hexane offorded a lithioderivative4which was methylated with methyl iodide in ether ‐ hexane. Deprotection of phenol group lead to o ‐ cresol (ring U‐14C) :6purified on a silicagal column with a 52% yield based on3. Nitration of6provided DNOC (ring U‐14C) with a 28% overall yield from phenol (ring U‐14C) ‐ Specific

ISSN:0362-4803    

DOI:10.1002/jlcr.2580170610

出版商:John Wiley&Sons, Ltd.    

年代:1980

数据来源: WILEY

摘要:

AbstractAttempted exchange experiments of morpholine, N‐methylmorpholine and N‐ethylmorpholine with a deuterium donor led to no deuterium incorporation in the morpholine rings. Morpholine‐d8is not found in the reaction of bromoethanol‐d5and ammonia, but it can be prepared from ethyleneoxide‐d4and ammonia. These reaction conditions are given for the H‐analog. N‐methylmorpholine‐d11is prepared from ethyleneoxide‐d4and methylamine‐d5N‐ethylmorpho‐Line‐d13is prepared in an analogous manner. N‐methyl‐d3‐morpholine is prepared from morpholine and diazomethane‐d2or from morpholine and methyliodide‐d3or from 2,2′‐bis‐(iodoethyr)ether and methyllamine‐d5N‐methyl‐N‐ethyl‐d5‐morpholinium(M.E.M.‐d5)‐iodide is preparea from N‐methylmorpholine and ethyliodide‐d5M.E.M.‐d16‐iodide and M.E.M.‐iodide are obtained by a similar route. N,N‐di‐(methyl‐d3)‐morpholiniumiodide is prepared from N‐methyl‐d3Morholine and methyliodide‐d3and also from morpholine and methyliodide‐d3M.E.M.‐(T.C.N.Q.‐d4)2; M.E.M.‐d5‐(T.C.N.Q.‐d4)2; M.E.M. d16‐(T.C.N.Q.‐d3)2; M.E.M.‐d16‐(T.C.N.Q.)2; and N,N‐di‐(methyl‐d3)‐ morpholinium‐(T.C.N.Q.)2are prepared fro

ISSN:0362-4803    

DOI:10.1002/jlcr.2580170611

出版商:John Wiley&Sons, Ltd.    

年代:1980

数据来源: WILEY