摘要:

AbstractThe title compound (mHCTPO) has been prepared to enhance sensitivity to molecular oxygen concentration in its Electron Spin Resonance (ESR) spectrum. The synthesis involved a novel variant of the traditional nitroxide synthesis leading to a much improved yield of mHCTPO over the several steps of the synthesis. An enhancement of T2spin label oxymetry with independent measurment of spin label concentration (from a spectral feature) has been observed. This molecule represents a new class of potentially valuable compounds forin vivoapplication and for imaging in ESR oxymetry.

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280602

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

Abstract[Cys‐14CO]‐glutathione or N‐[N‐L‐γ‐glutamyl‐L‐cysteinyl‐14CO] glycine was prepared by chemical synthesis, with the L,L‐natural configuration and a radiochemical yield of 1% based on sodium [14C] cyanide. This labelled compound was used to obtain [Cys‐14CO] with a yield of 15%. [Cys‐14CO]‐glutathione and [Cys‐14CO]LTC4had a specific activity of

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280603

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

Abstract[11C]‐acetone, prepared from11CO2and methyllithium, was reduced to [11C]‐isopropanol. The latter reacted with methylphosphonic acid difluoride in the presence of diisopropylamine, to yield [11C]‐sarin.3.4 GBq (100 mCi) of [11C]‐sarin may be obtained from about 55.5 GBq (1.5 Ci) of11CO2in 40 minutes. The product purified by HPLC, is obtained with a specific radioactivity ranging from 22.2 to 33.3 GBq (600 to 900 mCi

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280604

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

CY 233 (Ecomustine or SR 90098) is a new antitumour nitrosourea: it is characterized by a 2‐chloroethylnitrosourea substituent on a dideoxycarbohydrate. It has been labelled with14C on a) the carbonyl group of the urea in four stages starting with14COCl2, b) the second carbon of the chloroethyl group in four stages starting with [14C] ethanolamine, and c) on the methyl group on the anomeric centre of the carbohydrate in three stages starting with14CH3OH. The final position was also labelled with13C starting with13CH3OH. These differently labelled compounds are suitable for mechanistic studies of antitumour activit

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280605

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractThe design of a vacuum manifold for the synthesis of radiolabelled trimethyloxonium tetrafluoroborate from radiolabelled methyl iodide and triethyloxonium tetrafluoroborate is described.

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280606

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractA synthesis of ethyl (E)‐4‐[2‐(3,4‐dihydro‐4,4‐dimethyl‐2H‐1‐benzopyran‐6‐yl)‐1‐propenyl]benzoate‐9,10,11,20‐14C4(1) is described via a multistep procedure similar to that used to obtained the unlabelled compound2. The latter has shown good activity in several assays compared to the standardtrans‐retinoic acid (3). Treatment of methyl 3‐phenoxypropionate (4) with methylmagnesium iodide (obtained from H314C‐I) yielded the labelled tertiary alcohol5. Cyclization of the alcohol5occurred in the presence of AlCl3in nitromethane to give 4,4‐dimethylchroman (6). Acetylation of6with H3C14C(O)Cl produced ketone7labelled at three carbons. Reduction of the carbonyl group in7was effected with LiAlH4and gave alcohol8. Phosphorylation with triphenylphosphine hydrobromide in methanol led to the corresponding phosphonium salt9. Addition ofn‐butyllithium to9in ether at −78°C generated the expected Wittig reagentin situ, and to this was added labelled ethyl 4‐formylbenzoate [C2H5O214C‐C6H4‐CHO] (10). Workup, followed by chromatography of the oily product, afforded a solid. Recrystallization (abs. ethanol) gave1which was identical to2in terms of spectral data and melting point. The sp

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280607

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractThe naturally occurring dextrorotary enantiomer (+)‐pseudoephedrine,1, was synthesized (1) in the [3H]‐labelled form with specific activity 17.5 Ci/mmol suitable for development of a radioimmunoassay procedure. The chirally specific route fromL‐alanine to [1‐3H]‐d‐pseudoephedrine hydrochloride was based on the use of α‐amino acids as chiral educts for asymmetric products as develop

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280608

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractLa synthégse du peptide immunoactif RP 5614C a été réalisée par synthése peptidique en solution à partir de L‐alanine ∥14C−1) d'acitvité spgcifique 52.5 mCi/mmol (1

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280609

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractFour deuterated naphthalenes, ten deuterated anilines, three deuterated m‐toluidines, and five deuterated anisoles were prepared in high isotopic purities from the corresponding halo‐substituted derivatives by the reductive dehalogenation with Raney Cu‐Al alloy in an alkaline deuterium oxide sol

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280610

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractA convenient and inexpensive method for the preparation of [14C]‐labelled shikimic acid based on the photoassimilation of14CO2by henbane (Hyoscyamus niger L.) leaves in the presence of the herbicide glyphosate is described.Methanolic extracts were purified by successive anion exchange, paper and thin‐layer chromatography to yield [14C]‐labelled shikimic acid of 99.5% radiochemical purity, as shown by analytical HPLC. Under the conditions employed, the rate of incorporation of14CO2into shikimic acid (0.7 – 17.6%) showed a positive correlation with the size of the leaf used in the incubation (3.6 ‐ 146 mg fresh weight), while the specific activity of the acid (6 ‐ 12.7 GBq/mmol) was an inverse function of th

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280611

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY