摘要:

AbstractOchratoxin A is a mycotoxin produced byAspergillusandPenicilliummoulds. The toxin is an amide formed between phenylalanine and the isocoumarin acid ochratoxin α. Ochratoxin A with high specific radioactivity can be obtained, by substitution of the natural phenylalanine for14C or3H‐labelled phenylalanine. Labelled ochratoxin A was formed by condensation of labelled phenylalanine ethylester with an anhydride derivative of ochratoxin α. The intermediate O‐acetyl ochratoxin C was hydrolyzed with pig liver esterase and chymotrypsin to afford ochratoxin A. The overall yield of radioactivity was 50%. Specific activities up to 500 Ci/mol and 100 Ci/mmol for14C and3H respectively were obt

ISSN:0362-4803    

DOI:10.1002/jlcr.2580230802

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY

摘要:

AbstractZolpidem is a novel hypnotic agent possessing a substituted imidazo[1,2‐a] pyridine structure. The synthesis of the tritium labelled compound with a specific activity of 60.5 Ci/mmol is described. This new radioligand was initially used to establish and characterize the binding properties of Zolpidem in the rat brai

ISSN:0362-4803    

DOI:10.1002/jlcr.2580230803

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY

摘要:

Abstract(o‐[125I]iodobenzyl)benzylmethylselenonium tetrafluoroborate (1) and (o‐[125I]iodobenzyl)dibenzylselenonium tetrafluoroborate (2) were synthesized by methylation and benzylation ofo‐[125I]iodobenzyl benzyl selenide respectively. The starting compoundo‐iodobenzyl benzyl selenide was radioiodinated with sodium [125I]iodide by melt‐exchange in a sealed ampoule maintained at 75°C for 12 hours, with subsequent chromatographic purification yielding the pure compound in a radiochemical yield of 33.0% and specific activity of at least 68.0 mCi/mmol. Tissue distribution studies of compounds1and2, performed in rats, showed that the labelled compounds accumulated rapidly in the heart. The maximum heart‐to‐blood ratios for compounds1and2were 4.2:1 and 4.4:1 compared to that of 2.0:1 for previously synthesized [75Se]Trimethylselenon

ISSN:0362-4803    

DOI:10.1002/jlcr.2580230804

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY

摘要:

Four methods of syntheses of IDAZOXAN (RX 781094): |2‐(2‐imidazolinyl)‐1,4‐benzodioxane| labelled with tritium:1at high specific activity, a selective radioligand presynaptic α2‐ adrenoreceptor antagonist are described. 2‐carbethoxy‐1,4‐benzodioxine 5 was treated with tritium in benzene in presence of Wilkinson's catalyst leading to 2‐carbethoxy [2,3‐3H]‐1,4‐benzodioxane: 6 spec. act. 60 Ci/m which was then condensed in toluene with a reagent made from trimethylaluminium and ethylenediamine giving rise to1specific activity 44 Ci/mMole.2‐(carbamido N‐cyanomethyl)1,4‐benzodioxine:2was prepared from 2‐chlorocarbonyl‐1,4‐benzodioxine:10and 2‐aminoacetonitrile.2was reduced with tritium in trifluoroacetic acid in presence of Pd/C giving8which, without purification was ring closed into2by trimethylaminium treatment. Spec. act. 35.5 Ci/mMole. When reduced with tritium in presence of Wilkinson's catalyst,7gave9spect. act. 55 Ci/mMole. After purification9was again reduced with tritium in trifluoroacetic acid in presence of Pd/C, or PtO2, or Rh/Al2O3giving8which was cyclised into1by trimethylaluminium treatment in toluene. spec. act. of1was 41.5 ‐ 39 Curies/mMole.1was purified by successive preparative thin layer chromatography. The radiochemical purity checked by TLC and PLC was better than 99%. Some observations on the

ISSN:0362-4803    

DOI:10.1002/jlcr.2580230805

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY

摘要:

Abstract14C‐Bucromarone, 2‐[4‐(3‐N,N dibutylamino propoxy) 3,5‐dimethyl benzoyl] chromone, was synthesized from (U‐14C) oxalic acid. The labelling takes place at the first step of the synthesis, and allowed the obtention of−14C‐Bucromarone succinate, with a specific activity of 7.45 mCi/mmol, i.e. 275.6 MBq/mmol;−14C‐Bucromarone hydrochloride, with a specific activity of 7.5 mCi/mmol,

ISSN:0362-4803    

DOI:10.1002/jlcr.2580230806

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY

摘要:

AbstractS‐adenosyl‐L‐homocysteine and 5′‐methylthioadenosine were bitritiated specifically at C′‐5 for enzymatic assay of S‐adenosylhomocysteine nucleosida

ISSN:0362-4803    

DOI:10.1002/jlcr.2580230807

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY

ISSN:0362-4803    

DOI:10.1002/jlcr.2580230808

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY

摘要:

AbstractThe title compounds were obtained from the corresponding 6‐bromo derivatives by conversion to the 1,6‐dilithio‐compounds followed by treatment with deuteriated or tritiated water and exchange of the 1‐deuterium or tritium wit

ISSN:0362-4803    

DOI:10.1002/jlcr.2580230809

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY

ISSN:0362-4803    

DOI:10.1002/jlcr.2580230801

出版商:John Wiley&Sons, Ltd.    

年代:1986

数据来源: WILEY