Syntheses of 3,24R,25- and 3,24S,25-trihydroxy-5,7-cholestadiene 24,25-ketals and alkanoyl derivatives thereof, intermediates in the preparation of the biologically important metabolite and derivative, respectively, of vitamin D.sub.3, are described.
本文描述了3,24R,25-和3,24S,25-三羟基-5,7-胆甾二烯24,25-
缩醛和脂酰衍
生物的合成,这些是在制备
生物学上重要的
维生素D.sub.3的代谢产物和衍
生物的中间体。