highly selective low energy UV lamp in the presence of mercuric bromide. With this procedure cholesterol acetate, 5-cholestene-3 beta, 27-diol diacetate, 24(R)-24-methyl-5-cholesten-2 beta-yl acetate, 24(R)-24-ethyl-5-cholesten-28-yl acetate and 24(R)-24-ethyl-(22E)-cholesta-5,22-dien-3 beta-yl acetate were oxidized to the allylic keto-derivative in good yields; estradiol-17 beta diacetate was similarly
为了提供产率高于
化学氧化获得的7-氧
胆固醇的衍
生物,研究了甾体烯丙基或苄基酮的制备。在
溴化汞存在的情况下,使用高选择性低能量紫外灯研究了空气诱导的氧化。通过该程序,
乙酸胆固醇,
5-胆甾烯-3β,27
-二醇二
乙酸酯,24(R)-24-甲基-
5-胆甾烯-2β-
乙酸乙烯酯,24(R)-24-乙基-
5-胆甾烯-将
乙酸28-
乙酸酯和24(R)-24-乙基-(22E)-胆甾-5,22-二烯-3β-
乙酸乙酸酯氧化成烯丙基酮基衍
生物,收率很高。类似地,
雌二醇-17β二
乙酸酯以提高的产率转化为6-氧代产物。该方法在合成
乙酸7-氧
胆固醇酯及其类似物和6-氧-
雌甾烯中非常有用。