A MULTIGRAM PREPARATIVE SYNTHESIS OF CHOLEST-4-EN-3α,6β- AND -3α,6α-DIOLS
摘要:
A preparative synthesis of cholest-4-en-3 alpha ,6 beta- and -3 alpha ,6 beta -diols 10 and 15 using cheap reagents and simple working-up procedures without chromatography on a multigram scale is described.
19-nor-5β-Methyl-steroide, III. Die Acetolyse von 3-Methoxy-steroiden
作者:Günther Snatzke
DOI:10.1002/jlac.19656860120
日期:1965.7.15
y-Δ4-cholesten (III), 3β.6β-Diacetoxy-Δ4-cholesten (V) und dessen 3α-Epimeres (IVb) identifiziert werden. IV b und V entstehen durch Acetolyse aus dem 3β-Methoxy-Derivat III. Das 6-Monoacetat (VIc) des 5α-Cholestan-3α.5.6β-triols liefert mit SOCl2 ein cyclisches Sulfit VII, das 3-Monoacetat VId das entsprechende 5α.6α-Epoxyd IXb. Die Acetolyse gesättigter und ungesättigter 3β- und 3α-Methoxy-steroide
4,5-Epoxycholestane-3,6-diols: Templates for generating the full set of eight cholestane-3,5,6-triol stereoisomers in multigram scales, but not for a cholestane-3,4,6-triol
作者:Kejun Zhao、Yongfeng Wang、Li Han
DOI:10.1016/j.steroids.2006.11.015
日期:2007.1
Cholestane-3 beta,5 alpha,6 beta-triol is an extensively studied biologically important oxysterol. The full set of eight cholestane-3,5,6-triol stereoisomers was synthesised in diastereomerically pure forms by the stereoselective cleavage of eight diastereomerically pure 4,5-epoxycholestane-3,6-diols with LiAlH4, in high yields on multigram scales and without chromatography for most of them. However, applying various reportedly successful combinations of a hydride donor and a Lewis acid to the same substrates under a variety of conditions failed to generate a single unsubstituted cholestane-3,4,6-triol. The products of the eight cholestane-3,5,6-triol stereoisomers will serve as a good probe in the study of biological functions of oxysterols in a biological process. (c) 2006 Elsevier Inc. All rights reserved.
Circular Dichroism of some steroidal 6-membered ketoximes
A MULTIGRAM PREPARATIVE SYNTHESIS OF CHOLEST-4-EN-3α,6β- AND -3α,6α-DIOLS
作者:Kejun Zhao、Yongfeng Wang、David C. Billington
DOI:10.1081/scc-100105387
日期:2001.1.1
A preparative synthesis of cholest-4-en-3 alpha ,6 beta- and -3 alpha ,6 beta -diols 10 and 15 using cheap reagents and simple working-up procedures without chromatography on a multigram scale is described.