Novel synthesis of (24R,6E)-24-ethylcholest-6-hydroxyimino-4-en-3-one, a steroidal oxime fromCinachyrella spp. sponges
作者:N. B. Kovganko、Yu. G. Chernov
DOI:10.1007/bf02236428
日期:2000.3
(24R,6E)-24-ethylcholest-6-hydroxyimino-4-en-3-one (1), which was isolated previously from Cinachyrella spp. sponges, is synthesized in five steps from beta -sitosterol in 30% overall yield.
作者:Jayr de Paiva Campello、Sebastião Ferreira Fonseca、Ching-Jer Chang、Ernest Wenkert
DOI:10.1016/0031-9422(75)85047-3
日期:1975.1
Abstract Sitosterol and the following terpenic compounds have been isolated from the bark of Podocarpuslambertius: 3β-hydroxytotarol, 4β-carboxynortotarol, and macrophyllic and lambertic acids. The leaves yielded sitosterol, stigmastan-3β,5α-diol-6-one, isopimaric acid, phyllocladene, isophyllocladene, 8,9-abieten-15-ol and 17-isophyllocladenol.
Efficient trans-diaxial hydroxylation of Δ5-steroids
作者:João F.S. Carvalho、M. Manuel Cruz Silva、M. Luisa Sá e Melo
DOI:10.1016/j.tet.2010.01.089
日期:2010.3
A convenient, fast, and high-yielding process to synthesize 5 alpha,6 beta-dihydroxysteroids directly from the correspondent Delta(5)-steroids is reported. The reaction protocol consists in the conjugation of a readily available and stable oxidant, magnesium bis(monoperoxyphthalate) hexahydrate, with the non-toxic bismuth(III) triflate in acetone to afford the trans-diaxial hydroxylation product in a stepwise manner and in excellent yields. (C) 2010 Elsevier Ltd. All rights reserved.
SOUTH AFRICAN GEOMORPHOLOGY: CRITICAL CHOICES FOR THE FUTURE
作者:H. R. BECKEDAHL、P. D. SUMNER、G. GARLAND
DOI:10.1080/03736245.2002.9713765
日期:2002.3
Murakami, Takao; Wada, Hiroshi; Tanaka, Nobutoshi, Chemical and pharmaceutical bulletin, 1980, vol. 28, # 10, p. 3137 - 3139