摘要:

Abstract[14C]Pelrinone (1,4‐dihydro‐2‐methyl‐4‐oxo‐6[(3‐pyridinylmethyl)‐amino]‐5‐pyrimidine‐[14C]‐carbonitrile hydrochloride; AY‐28,768 hydrochloride), a potent inotropic agent, was prepared by reacting chloroacetic acid with [14C]sodium cyanide to give the labelled cyanoacetic acid. The acid was esterified, converted to the bis‐S‐methyl compound, condensed with acetamidine hydrochloride, coupled with 3‐aminomethylpyridine, and treated with methanolic hydrochloric acid. Two batches of [14C]pelrinone were produced, giving a combined overall yield of 15.6% from [14C]sodium cyanide (sp. act. 66.2 ± 1.5 and 64.2 ± 1.9 μCi/mg; 98.8 and 98.0% r

ISSN:0362-4803    

DOI:10.1002/jlcr.2580240703

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY

摘要:

AbstractA description of the preparation of methyl 3‐oxo‐4,4‐dimethylpentanoate‐1,3‐14C. The Grignard reagent prepared from 2‐chloro‐2‐methylpropane is carbonated with14CO2and the resulting trimethylacetic acid treated with methyllithium. 3,3‐Dimethyl‐2‐butanone is treated with NaNH2, the resulting enolate is carbonated with14CO2, and this ketoacid treated immediately after workup wit

ISSN:0362-4803    

DOI:10.1002/jlcr.2580240704

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY

摘要:

AbstractThe compound 2,6‐dichlorobenzonitrile (dichlobenil, DCB) is known to be a reversible inhibitor of in vivo cellulose biosynthesis in higher plants and algae. We now report the synthesis of 2,6‐dichlorophenylazide (DCPA) with a non‐exchangeable tritium label of high specific activity. We have shown this compound to compete with DCB in binding to cotton fiber extracts, and to specifically label a low molecular weight protein in this extract on irradiation with UV

ISSN:0362-4803    

DOI:10.1002/jlcr.2580240705

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY

摘要:

AbstractSeveral catalytic hydrogen‐tritium exchange procedures have been investigated in order to accomplish uniform and random incorporation of tritium into the diverse organic components present in two engine oil basestocks. The most successful procedure involved the use of Raney nickel and tritiated water at elevated temperatures. Comparative proton and tritium nuclear magnetic resonance spectroscopy shows that the incorporated tritium was representative of the organic components present in the basestocks. Comparative gas‐ and radio‐gas chromatography studies provided supplementary information. These investigations demonstrate that engine oils can be satisfactorily labelled with tritium for studies of engine oil consum

ISSN:0362-4803    

DOI:10.1002/jlcr.2580240706

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY

摘要:

AbstractOxygen‐18 isotope labeled at the carboxyl group of glycine, L‐alanine and L‐proline were synthesized by acid catalyzed exchange or acid hydrolysis of respective methyl ester derivatives of amino acids in HC1/H218O. Quantitative enrichment of glycine was achieved by the acid hydrolysis of amino acetonitrile in H218O. In order to conserve the isotopic enrichment [18O] dipeptides were synthesized by solid phase method. [18O] isotope effects on [13C] NMR of carboxylic carbon of amino acids and carbonyl carbon of peptides was observed. The [18O] isotopic shifts observed for the carboxylic carbon of singly and doubly [18O] labeled amino acids showed that the [18O] isotope effect is add

ISSN:0362-4803    

DOI:10.1002/jlcr.2580240707

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY

摘要:

AbstractLevamisole, thelevoisomer of tetramisole, is a potent anthelmintic also showing immunotropic properties. Renewed interest in the latter domain necessitated the synthesis of specifically3H‐labelled levamisole of high specific activity.Racemic 1‐(2‐bromophenyl)‐1,2‐ethane diamine dihydrochloride (V) was obtainedviabromination of 1‐(2‐bromophenyl)ethanone (I), followed by reaction with 2,5‐pyrrolidinedione, Leuckart amination and hydrolysis. The racemate was then resolved by successive salt formation with (S)‐(‐) and (R)‐(+) tartaric acid. The liberated (S)‐(+)‐base ofVIwas dehalogerated with approximately 30 Ci of tritium gas and immediately ring‐closed with carbon disulfide toVIII. The HPLC‐purified material was finally cyclized with 1,2‐dibromo ethane to (S)‐(‐)‐2,3,5,6‐tetrahydro‐6‐[2‐T]phenyl‐imidazo‐(2,1‐b)‐thiazoleIXand the isomerically ringclosed (S)‐2,3,5,6‐tetrahydro‐5‐[2‐T] phenyl‐imidazo‐(2,1‐b)‐thiazoleX, of which levamisoleIXwas isolated via HPLC. The radiochemical yield over the cyclization steps was 28.2 %, the sp

ISSN:0362-4803    

DOI:10.1002/jlcr.2580240708

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY

摘要:

AbstractThe synthesis and spectroscopic properties of the title compound as well as its precursors are described.

ISSN:0362-4803    

DOI:10.1002/jlcr.2580240709

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY

摘要:

Abstract2‐Isopropyl‐8,9‐dimethoxy‐benzofurano [2,3‐b]furo[2,3‐h][1] [11‐14C]benzopyran‐6‐one (IVb) and 3‐(2‐hydroxy‐4,5‐dimethoxyphenyl)‐4‐hydroxy‐5′‐isopropylfurano[2′,3′:7,8] [2‐14C]coumarin(Vb) were prepared from isorotenone (Ib) for use in metabolic and other studies. Deoxybenzoin derivative (IIb), obtained from isorotenone, was reacted with ethyl [14C] formate in the presence of sodium to give the corresponding [2‐14C]‐2′‐hydroxyisoflavone (IIIb), which was transformed into the14C‐labeled benzofurano [2,3‐b]furo[2,3‐h]benzopyran‐6‐one compound (IVb) by the subsequent oxidative cyclization with selenium dioxide. Hydrolysis of compound

ISSN:0362-4803    

DOI:10.1002/jlcr.2580240710

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY

摘要:

AbstractA process is described for preparing routinely sterile and pyrogenfree, multimillicurie amounts of 2‐[18F]‐fluoro‐2‐deoxy‐D‐glucose (18F‐2FDG) with and without carrier‐added fluoride and with a radiochemical purity of greater than 98% without the use of preparative HPLC. For 13 consecutive runs, the radiochemical yield with carrier‐added fluoride was 35.5 ± 2.2%. The [18F]fluoride used was produced by the reaction160(3He, p)18F or by the reaction180 (p,n)18F. Analytical HPLC,1H and19F NMR spectral analysis were used to establish the identity and

ISSN:0362-4803    

DOI:10.1002/jlcr.2580240711

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY

摘要:

AbstractNine deuterium‐labelled α‐tocopherols having the natural, 2R,4′R,8′R, stereochemistry have been synthesized for study by2H NMR of the orientation and dynamics of natural α‐tocopherol in a phospholi

ISSN:0362-4803    

DOI:10.1002/jlcr.2580240712

出版商:John Wiley&Sons, Ltd.    

年代:1987

数据来源: WILEY