ISSN:0362-4803    

DOI:10.1002/jlcr.2580250202

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

Abstract1‐Ferrocenyl‐2‐amino‐alkyls were synthezised and labelled with deuterium in the side chain. An additional labelling with deuterium was possible in the alkyl group of theN‐alkyl‐derivatives. By reaction of103RuCl3with the ferrocene compounds the ruthenocene analogues were labelle

ISSN:0362-4803    

DOI:10.1002/jlcr.2580250203

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractThe syntheses of D/L‐ and L‐Se‐[methyl‐11C]selenomethionine are reported. The Se‐benzyl selenohomocysteines were deprotected in sodium/liquid ammonia and the selenide anions generatedin situwere alkylated with [11C]methyl iodide to give, after purification by LC, the products in 80 to 85 % radiochemical yield, with a radiochemical purity higher than 99 % within 30 min and with a specific radioactivity of 20 to 200 mCi/μmol. The enantiomeric purity of the L‐compound, determined by LC, was high

ISSN:0362-4803    

DOI:10.1002/jlcr.2580250204

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractThe synthesis of3H‐labelled Met‐enkephalin and Tyr‐D‐Ala‐Gly‐Phe‐Met‐NH2(DALA) and14C‐labelled Substance P (SP) from previously described, fully protected intermediates is reported. The labelled peptides were prepared by methylation with (3H)‐ or (14C)methyl iodide of the sulphide anions formed on deprotection of the corresponding S‐benzyl‐homocysteine precursors with sodium in liquid ammonia. After purification by LC, the labelled peptides were obtained in radiochemical yields in the range of 9 to 24 % with a radiochemical purity higher than 97%. The specific radioactivities of the3H‐ and14C‐labelled products, corresponding to the labelled methyl iodides used, were 80 mCi/μmol an

ISSN:0362-4803    

DOI:10.1002/jlcr.2580250205

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractThe synthesis of three S‐[methyl‐11C]‐labelled enkephal in analogues, iyr‐D‐Ala‐Gly‐Phe‐Met‐NH2, Tyr‐D‐Ala‐D‐Ala‐Phe‐Met‐NH2and Tyr‐D‐Met‐Gly‐Phe‐Pro‐NH2, from the corresponding S‐benzyl‐homocysteine‐containing peptides is reported. The protected pentapeptide amides were prepared by (3+2) fragment condensations in solution. These peptides were subsequently deprotected with sodium in liquid ammonia and the sulphide anions formed alkylated with [11C]‐methyl iodide to give the S‐[methyl‐11C]‐labelled enkephalins. After purification by preparative LC, these labelled peptides were obtained in 55 to 75 % radiochemical yield, decay corrected, based on the [11C]methyl iodide produced, within 30‐40 min from start of the synthesis of this reagent. The radiochemical purities of the products were higher than 98 %, an

ISSN:0362-4803    

DOI:10.1002/jlcr.2580250206

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractA potent and long acting calcium antagonist YM‐09730‐5, (3S)‐1‐benzyl‐3‐pyrrolidinyl methyl (4S)‐2,6‐dimethyl‐4‐(m‐nitrophenyl)‐1,4‐dihydropyridine‐3,5‐dicarboxylate hydrochloride (7a·HCl), was labeled with carbon‐14 and deuterium. The labeled materials were prepared by either the cyclizing Michael addition of 3‐aminocrotonate (5c) to benzylidene acetoacetate (6) or the modified Hantzsch reaction usingm‐nitrobenzaldehyde, aminocrotonate(5a) and acetoacetate (3b). The14C‐labeled material (7c·HCl) was synthesized from methyl [3‐14C]acetoacetate (4c) in a 32.0% radiochemical yield, at a specific activity of 60.9 mCi/mmol. The deuterium labeled material (7b·HCl) was synthesized from 1‐benzyl‐3‐hydroxypyrrolidine‐d4(2b) which was obtain

ISSN:0362-4803    

DOI:10.1002/jlcr.2580250207

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractThe synthesis of 7α‐methoxycarbonyl‐15β,16β‐methylene‐3‐oxo‐17α‐pregn‐4‐ene‐21,17‐carbolactone (5, SH‐D515, ZK 91587), a potent aldosterone antagonist exhibiting a strong and very selective binding to the mineralocorticoid receptor and the t

ISSN:0362-4803    

DOI:10.1002/jlcr.2580250208

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractThe α1‐adrenoreceptor antagonist, Prazosin : 2‐[4‐(2‐furoyl) piperazin‐1‐yl]‐4‐amino‐6,7‐dimethoxyquinazoline, has been labelled with carbon‐11 for in vivo studies of α1‐adrenoreceptors using positron emission tomography. The preparation of [2‐11C] furoyl chloride, from cyclotron‐produced [11C] carbon dioxide, and its reaction with the secondary amine, 2‐(piperazin‐1‐yl)‐4‐amino‐6,7‐dimethoxyquinazoline, provides a fast (35 min) route to carbon‐11 labelled prazosin in high radiochemical yield (30‐40 %, decay‐corrected) with high sp

ISSN:0362-4803    

DOI:10.1002/jlcr.2580250209

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractThe preparation and introduction of fluoroacyl moieties as prosthetic groups is described for n.c.a. labelling with fluorine‐18. Activation by the aminopolyether 2.2.2./K2CO3complex was used for the nucleophilic18F‐exchange in α‐substituted acid esters. Increasing yields were found in the sequence: iodo<

ISSN:0362-4803    

DOI:10.1002/jlcr.2580250210

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractThe fluoroalkylation of H‐acidic compounds in the presence of the aminopolyether 2.2.2./potassium carbonate complex was systematically studied. With acetonitrile as solvent nucleophilic fluorination and subsequent fluoroalkylation can be carried out in a one‐pot mode. Using the bifunctional fluoroalkanes18F(CH2)nX (n = 1‐3, X = Br, OMes, OTos) the best n.c.a. labelling yields were obtained with tosylates. Fluoroethylation and fluoropropylation of phenol gave rise to radiochemical yields of ≥ 90% under optimized conditions within 10 min. The fluoroethyl moiety is the smallest generally applicable fluoroalkylation agent. In a series of H‐acidic compounds a strong influence of their pKavalue on the fluoroethylation reaction was observed. Besides H‐acidic compounds all Lewis bases are principally potential substrates for n.c.a.18F‐flu

ISSN:0362-4803    

DOI:10.1002/jlcr.2580250211

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY