摘要:

AbstractVarious Carbon–14 labelled amino acids including the aromatic ones viz., tyrosine, phenylalanine and tryptophan are converted to the corresponding carboxylic acids in high yield (70–;90%) on a micromolar scale synthesis by reaction with hydroxyl‐amine‐o‐sulphonic acid and in a short reaction time. The improvement in yield has been achieved by using aqueous alcohol as solvent in lieu of water alone as the medium of

ISSN:0362-4803    

DOI:10.1002/jlcr.2580250802

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractA one step procedure for the preparation of labeled mevinolin analogs4,10and15possessing the 2,2‐dimethylbutyryloxy side chain is described. The lactones1,7and13were converted into potassium salts of their corresponding di or trihydroxy carboxylic acids from which anionic ester enolates were generated and alkylated with [14C]methyl iodide. Workup and purification by reverse phase HPLC provided radiochemically pure4,10and15. The labeled lactones were converted into ammonium salts of their corresponding di or trihydroxy acid

ISSN:0362-4803    

DOI:10.1002/jlcr.2580250803

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractRitanserin has been labelled with18F to visualize the serotoninergic receptors by Positron Emission Tomography (PET). The synthesis was carried out by a nucleophilic substitution of a nitro substituent of a nitrophenylketone by18F−and then addition of a Grignard reagent to the ketone followed by dehydration of the tertiary alcohol so formed.The total time to have [18F]ritanserin ready for injection into a patient was 150 minutes (after the end of bombardement for the18F production [18O (p,n)18F]).The labelling technique described was used to obtain 1.1 to 1.5 GBq (30 to 40 mCi) of [18F]Ritanserin with a specific activity of 44 GBq/μmol (1.2 Ci/μmol) starting from 18.5 GBq (500 mCi)

ISSN:0362-4803    

DOI:10.1002/jlcr.2580250804

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractOxygen Isosteres of hydroxy‐di‐n‐propylaminotetralines. Syntheses of racemic monomethoxy and monohydroxy‐3‐(di‐n‐[3H‐propyl] amino) chromanes: new Radioligands for 5–HT1Aand D2receptors sites labelling.Condensation of monomethoxy salicylaldehydes:4a–dwith nitroethanol gave methoxy‐3‐nitro‐2H chromenes5a–dwhich were reduced with LAH into methoxy‐3‐amino chromans6a–d. Two syntheses of 2‐hydroxy‐6‐methoxy‐benzal‐dehyde:4awere described. N‐alkylations of6a–dwere carried out a/ by Borch procedure b/ by n‐propylation with propyl iodide in presence of bases c/ by allylation in presence of bases. Methoxy‐3‐(diallyl‐amino) chromans:13a–dwere catalytically reduced with hydrogen (Pd/C in methanol) into mixtures of methoxy‐3 (di‐n‐propylamino) chromans2a–dand methoxy‐3‐ (n‐propylamino) chromans resulting from the hydrogenolysis of one allyl group.Methoxy‐3‐dialkylamino chromans2a–dand13awere O‐demethylated either by boiling 48% HBr or by BBr3in CH2Cl2.Catalytic hydrogenation with tritium of precursors13a–dand15ain methanol in presence of 10% Pd/C gave [3H] – 5. OH‐DPLC:3a; [3H] 5. OMe‐DPAC:2aand the isomers:2b‐2dwhich were purified by HPLC, analyzed by reversed HP

ISSN:0362-4803    

DOI:10.1002/jlcr.2580250805

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

Abstract[1‐14C]‐Dilevalol, (Figure 1), was synthesized from [1‐14C]‐acetyl chloride. A key step in the synthesis, the coupling of a protected chiral amine with a bromoketone, was very sensitive to the choice of protecting group. The authors attribute this sensitivity to unexpected and severe radiolytic decomposition of the reaction product. The use of a simple benzyl. protecting group rather than an α‐methyl benzyl protecting group avoided most of the apparent auto

ISSN:0362-4803    

DOI:10.1002/jlcr.2580250806

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractThis report describes the synthesis of arbaprostil, a cytoprotective antiulcer agent, and a group of related 15‐methylprostaglandins, labeled with tritium at the C‐11 position, from 15(R)‐ and 15(S)‐15‐methylprostaglandin D2methyl esters. Radiolytic decomposition of the labeled product and some intermediates, and purification by preparative high performance liquid chromatography, and storage of [3H]‐arbaprostil are als

ISSN:0362-4803    

DOI:10.1002/jlcr.2580250807

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractThe aliphatic amines, 2‐methyl‐ and 2‐isopropyl‐ substituted 6‐hydroxy −1 ‐hexylamines were synthesized from ethyl‐6‐hydroxyhexanoate in 22% and 11% overall chemical yield respectively. 6‐hydroxy‐ 1 ‐hexylamine was available commercially. 6‐hydroxy −1 ‐hexylamine and its 2‐methyl‐ and 2 ‐isopropyl‐ substituents were successfully radioiodinated with trimethylsilyl polyphosphate and [131I]‐Nal/Nal to afford the corresponding 6‐[131I]‐labelled amines in 67%, 61% and 55% radiochemical yield respectively and greater than 98% radiochemica

ISSN:0362-4803    

DOI:10.1002/jlcr.2580250808

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractThis report describes the synthesis of carbon‐14 labeled title compound from [14C]CS2. The substituted benzimidazole was labeled at the C‐2 position of the benzimidazole moi

ISSN:0362-4803    

DOI:10.1002/jlcr.2580250809

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractTrois dérivés tritiés de l'ANF (1‐28) de rat : (3H‐4‐Phe8)ANF, (3H‐4‐Phe26)ANF et (3H‐4‐Phe8,3H2‐3,5‐Tyr28)ANF ont été obtenus à partir de précurseurs halogénés. Les activités biologiques sont conservées et les activités spécifiques obtenues sont de l'ordre de 20 Ci/mMole (740 GBq/mMole) et 55 Ci/mMole (2035 GBq/mMole) respectivement pour les peptides mono‐ et tri‐tritiés.Au cours de la synthése, il y a formation de l'analoque linéaire radioact

ISSN:0362-4803    

DOI:10.1002/jlcr.2580250810

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractGeraniol was formed in high (up to 36%) yield when equimolar quantities of isopentenyl and 3,3‐dimethylallyl pyrophosphates (1 mmole) together with inhibitors of the isomerase that interconverts them were incubated with a strictly defined cell‐free extract from flowerheads ofRosa dilectacv. Lady Seaton. The C5units were incorporatedin totowith essentially (>98%) complete position specificity. A simple route is thus available, given the appropriately labelled C5precursors, for the preparation of geraniol and thence by standard chemical routes of its isomers nerol and linalool and their pyrophosphates with any chosen carbon atom specifically labelled at isotope abundances suitable for biosynthetic studies. Similarly, any desired2H or3H labelled geraniol or its relatives could in principle be prepared with both regio‐ and stereo‐spec

ISSN:0362-4803    

DOI:10.1002/jlcr.2580250811

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY