摘要:

Abstract17α ‐E‐Bromovinylestradiol and its radiobrominated analogs were prepared by halodestannylation. The synthesis was achieved by bromination of the tri‐n‐butylstannylvinyl intermediate to give a 90% isolated yield. The reaction of the intermediate with ammonium [82Br] bromide or sodium [17Br] bromide in the presence of an oxidant give the corresponding radiolabeled bromovinylestradiol in 80–90% yields after isolation by HPLC. The radiochemical purity was greater than 98% and no other UV‐active compounds could be detected by HPLC. Anin vivocomparison of this compound with the previously prepared 17α ‐E‐[125I]iodovinyl estradiol indicated that the two compounds had similar uterine uptake and specific receptor binding properties. The results suggest that radiobromodestannylation may be the method of choice for the preparation of this and other structurally

ISSN:0362-4803    

DOI:10.1002/jlcr.2580270602

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

摘要:

AbstractA convenient, one step method for the preparation of deuterium or tritium labelled norethynodrel, norethindrone, and 6‐methyleneandrostenedione is reported which utilizes water as the source of label. The choice of exchange reagent (lithium or sodium hydroxide) is crucial in controlling rearrangement of the chemically labile β, γ unsaturated carbonyl function of norethynod

ISSN:0362-4803    

DOI:10.1002/jlcr.2580270603

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

摘要:

AbstractN‐nitro [14C]methylamine was synthesized by the alkaline cleavage of N‐nitro[methyl‐14C] methylurethane obtained by nitration of [N ‐ methyl‐14C] methylurethane. N‐nitro[N‐methyl‐14C]dimethylamine could be obtained by methylation of monomethylnitramine with [14

ISSN:0362-4803    

DOI:10.1002/jlcr.2580270604

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

摘要:

AbstractWarfarin (cyclic hemiketal form: 2‐hydroxy‐2‐methyl‐4‐phenyl‐3,4‐dihydro‐2H,5H‐pyrano[3,2‐c][1]benzopyran‐5‐one) is labeled with 98+%13C at the anomeric carbon (C2) and resolved into its enantiomers. Acetone‐2‐13C(98.6%) condenses with benzaldehyde in aqueous base to produce 4‐phenyl‐3‐buten‐2‐one‐2‐13C(98+%). Michael‐type addition of this to 4‐hydroxycoumarin in methanol produces the labeled diastereomeric warfarin methyl ketals which on deprotection form racemic warfarin‐2‐13C(98+%). Classical resolution of labeled warfarin with quinidine produces partly resolved (S)‐(–)‐warfarin‐2‐13C(98+%). Labeled warfarin is a suitable probe for warfarin conf

ISSN:0362-4803    

DOI:10.1002/jlcr.2580270605

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

摘要:

AbstractTen mCi of14C ethylene was converted to 1.16 mCi of14C PVPA by oxidative phosphonation with phosphorus trichloride and molecular oxygen, dehydrohalogenation with triethylamine in ether, polymerization, and hydrolysis. The polymer had a specific activity of 12 uCi/mg and a radiochemical purity over 99%.

ISSN:0362-4803    

DOI:10.1002/jlcr.2580270606

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

摘要:

Abstract4‐Fluoro‐1–[1–(2‐thienyl)‐3‐cyclohexenyl)] piperidine was efficiently synthesized in four steps starting from cyclohexane‐1, 4‐dione monoethylene ketal. Catalytic tritiation of this key intermediate in the final step afforded t

ISSN:0362-4803    

DOI:10.1002/jlcr.2580270607

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

摘要:

AbstractA one‐pot synthesis of [11C] labeled tamoxifen has been developed via reductive carboxylation. In this approach, [11C]CO2is reacted with the N‐trimethylsilyl derivative of desmethyltamoxifen, followed byin situsodium bis (2‐methoxyethoxy)aluminum hydride reduction, to afford impure [11C] labeled tamoxifen, which, on purification over a basic alumina‐silica gel column, provided pure [11C] tamoxifen in excellent radiochemical yield (65% to 84%) and radiochemical purity (>99%). The specific activity of [11C]tamoxifen was 250–400 Ci/mmol at the end of bo

ISSN:0362-4803    

DOI:10.1002/jlcr.2580270608

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

摘要:

AbstractThe syntheses of [2‐14C] 3′ ‐deoxythymidin‐2′ ‐ene (d4T) and [5‐125I] 3′ ‐azido‐2′, 3′ ‐dideoxy‐5‐iodouridine in a on

ISSN:0362-4803    

DOI:10.1002/jlcr.2580270609

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

摘要:

AbstractTwo tritium labelled trichothecenes, verrucarol (2) and verrucarin A (5) were synthesized with high specific activity. Oxidation of verrucarol (1) to the 15‐dehydroverrucarol (3) followed by sodium borotritide reduction yielded [15‐3H]‐verrucarol (2). Reduction of 16‐mesyloxyverrucarin A (7) in a special buffer‐organic solvent system with a phase transfer catalyst, produced [16‐3H]‐verrucarin A (5). Final purification of the radioactive products was achieved by preparative thin layer chromatography. Their structures were assigned based on the analytical data of the corresponding nonradiolabelled compounds obtained from the nonradioactive

ISSN:0362-4803    

DOI:10.1002/jlcr.2580270610

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY

摘要:

Abstract[Pyrimidine‐5‐3H]2′, 3′‐dideoxycytidine and [ribose 2,3‐3H]2′, 3′‐dideoxyinosine are prepared by catalytic reduction with tritium gas. [Adenine‐8‐3H]2′3′‐dideoxyadenosine is prepared by catalytic exchange with tritium gas. [Hypoxanthine‐8‐3H]2′,3′‐dideoxyinosine is prepared by the action of adenosine deaminase on

ISSN:0362-4803    

DOI:10.1002/jlcr.2580270611

出版商:John Wiley&Sons, Ltd.    

年代:1989

数据来源: WILEY