期刊名称：Journal of Nutritional Science and Vitaminology
印刷版ISSN：0301-4800
电子版ISSN：1881-7742
出版年度：1975
卷号：21
期号：6
页码：411-420
DOI：10.3177/jnsv.21.411
出版社：Center for Academic Publications Japan
摘要：1. The natural abundance carbon-13 nmr of vitamins D (D2 and D3) and several isomers (5, 6- trans -vitamin D2, isotachysterol2 and isovitamin D2) have been completely assigned by employing offresonance noise-decoupling, acetylation shifts, and lanthanide-induced shifts experiments. The last two techniques were especially useful for the present study. 2. Carbon-13 nmr spectral characteristics of the three main conjugated triene moieties ( sE - Z - sZ, sE - E - sZ , or sE - E - sE ), involved in the molecules of vitamin D and its isomers, were revealed. Thus, the striking dependence of the shieldings on molecular geometries and high sensitivity of the resonances to the environments of conjugated systems were surveyed. 3. Conformational preferences in solutions of the hydroxyl groups in vitamins D2 and D3 as well as 5, 6- trans -vitamin D2 were conveniently determined.
