摘要:

AbstractA nine‐step procedure for microscale synthesis of ethyl 2‐amino‐6‐{[(4‐fluorophenyl)methyl]amino}‐3‐pyridinyl‐2,6‐14C carbamate maleate [10], [14C]flupirtine maleate, was developed. The synthesis started with the readily avaiable and economical reagents, potassium cyanide‐14C and 1,3‐dibromopropane making the following intermediates: glutaronitrile‐14C [2], glutarimide‐14C [3], 2,6‐dichloropyridine‐2,6‐14C [4], 2,6‐dichloro‐3‐nitro‐pyridine‐2,6‐14C [5], 2‐amino‐3‐nitro‐6‐chloropyridine‐2,6‐14C [6], 2‐amino‐3‐nitro‐6‐(p‐fluorobenzylamino)pyridine‐2,6‐14C [7], 2,3‐diamino‐6‐(p‐fluoro‐benzylamino)pyridine‐2,6‐14C [8], and ethyl 2‐amino‐6‐{[4‐fluoropheny(l)‐methyl]amino}‐3‐pyridinyl‐2,6‐14C carbamic acid ester hydrochloride [9]. The overall yield was 6.3% (5.4 mCi), and the radioac

ISSN:0362-4803    

DOI:10.1002/jlcr.2580240102

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY

摘要:

AbstractThe synthesis of the title compound (6) is described. The reaction of sodium [14C] formate with acetyl chloride produced the mixed anhydride. Treatment with pyrrolidine gave the N‐formyl compound in a 4 to 1 ratio with the N‐acetyl compound.1Separation and reduction with lithium aluminum hydride gave N‐[14C]methylpyrrolidine2. Reaction with 7‐[α‐(2‐triphenylmethylaminothiazol‐4‐yl)‐α‐(z)‐methoximinoacetamido]‐1‐oxo‐3‐iodomethyl‐3‐cephem‐4‐carboxylate diphenylmethyl ester introduced the label into the cephalosporin. Treatment with acetyl chloride converted the sulfoxide to the sulfide. Formic acid at 39°C removed the protecting groups and treatment with 4N sulfuric acid produ

ISSN:0362-4803    

DOI:10.1002/jlcr.2580240103

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY

摘要:

AbstractA practical synthesis of [14‐3H]dibenz[a,j]acridine and [7‐3H]dibenz[a,h]acridine is reported from the parent hydrocarbon by catalytic exchange with tritium gas in the presence of palladium on calcium carbonate. Analogous regiospecific labelling with deuterium was also affected. In addition [14‐14C]dibenz[a,j]acridine was prepared from [14C]paraformald

ISSN:0362-4803    

DOI:10.1002/jlcr.2580240104

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY

摘要:

AbstractSelectively ring‐labelled terodilines (N‐tert‐butyl‐1‐methyl‐3,3‐diphenylpropylamine;1) were prepared by homogeneous catalytic exchange of aromatic hydrogens for3H and2H. In addition, terodilines specifically labelled with14C,3H or2H were prepared from the appropriate 1‐methyl labelled 4,4‐diphenylbutan‐2‐ol, by treating the corresponding tosylates withtert‐butylamine.Emepronium bromide (N‐ethyl‐N,N,1‐trimethyl‐3,3‐diphenylpropylammonium bromide;2) specifically labelled with14C or2H were similarly prepared by treating the labelled tosylates with N‐ethylmethylamine or dimethylamine, followed by quaternization with methyl bro

ISSN:0362-4803    

DOI:10.1002/jlcr.2580240105

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY

摘要:

AbstractThe synthesis of FCE 22101 (sodium (5R,6S)‐6‐[(1R)‐hydroxyethyl]‐2‐carbamoyloxymethylpenem‐3‐carboxylate) labelled with carbon‐14 in the 2‐position of the penem system ring was performed in eight steps, using sodium salt of [1‐14C]glycollic acid1as the labelled starting material. The final product, penem [2‐14C]FCE 2210111, was obtained in an overall radiochemical yield of 21%, 98% radiochemically pure and with a specific activity of 641 MBq/mmol (17.3 mCi/mmol). The acetoxymethyl ester FCE 2289112was prepared by condensation of11with bromomethyl acetate

ISSN:0362-4803    

DOI:10.1002/jlcr.2580240106

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY

摘要:

Abstract[1‐14C]Glyceric acid has been reduced to [13]‐14Clglycerol in high yields via the methyl ester of 1‐14Clglyceric acid by sodium borohydride in the presence of t‐butyl alcohol and methanol. The importance of the procedure is highlighted in relation to other procedures involving lithium aluminium hydride re

ISSN:0362-4803    

DOI:10.1002/jlcr.2580240107

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY

摘要:

AbstractNucleophilic aliphatic substitution of alkyl halides,1, [(CH2)nX2(n=2, 3; X=Br,I)], with NCA K[18F]/Kryptofix 2.2.2 in CH3CN gave the corresponding NCA [18F]fluoroalkyl halides2in 30–40% yields. The factors which influence the yield of2were compared.N‐Alkylation of several neurotransmitter receptor active amides and amines with this reagent gave the corresponding NCAN‐[18F]fluoroalkyl derivatives (3–6) in 20–

ISSN:0362-4803    

DOI:10.1002/jlcr.2580240108

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY

摘要:

AbstractThe title compounds were prepared for metabolic studies, with the14C labelling being made at methyl of the 1‐methyl‐1H‐tetrazol‐5‐ylthio (NMTT) group in overall radiochemical yields of 26% and 22% based on barium [14C]carbonate, res

ISSN:0362-4803    

DOI:10.1002/jlcr.2580240109

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY

摘要:

Abstract2‐exo‐Vinylbicyclo[2.2.1]hept‐5‐en‐2‐ols, specifically labeled with2H at C‐3 and in the vinyl group were prepared from bicyclo [2.2.1]hept‐5‐en‐2‐one in several steps. [4‐13C]Oct‐1‐en‐3‐one was prepared in five steps from13CO2. These compounds serve as precursors for the preparation of specifically labeled neutral and i

ISSN:0362-4803    

DOI:10.1002/jlcr.2580240110

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY

摘要:

AbstractAntibodies labelled with radioisotopes via chelating agents are being used increasingly for in vivo localisation or radiotherapy of tumours. The most widely used chelating agent is DTPA. Here, we describe technical modifications of the standard DTPA cyclic anhydride conjugation procedure and determine the in vitro stability of the DTPA‐antibody conjugates. The use of this derivative of DTPA combined with the use of appropriate buffers and small disposable gel filtration columns resulted in the development of a simpler and more rapid technique for the production of DTPA‐conjugated antibod

ISSN:0362-4803    

DOI:10.1002/jlcr.2580240111

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY