申请人:William Marsh Rice University
公开号:US04897475A1
公开(公告)日:1990-01-30
A process for preparing 15-oxygenated sterols, such as 3.beta.-hydroxy-5.alpha.-cholest-8(14)-ene-15 one, comprising converting 7-dehydrocholesterol to 3.beta.-benzoyloxycholesta-5,7-diene, converting the 3.beta.-benzoyloxycholesta-5,7-diene to a 3.beta.-benzoyloxy-5-cholesta-7,14-diene, converting the 3.beta.-benzoyloxy-5-cholesta-7,14-diene to a 3.beta.-benzoyloxy-14.alpha., 15.alpha.-epoxy-5-cholest-7-ene and converting the 3.beta.-benzoyloxy-14.alpha., 15.alpha.-epoxy-5-cholest-7-ene to a 15-oxygenated sterol. Preferably, the 3.beta.-benzoyloxy-cholesta-5,7-diene is converted to a 3.beta.-benzoyloxy-5-cholesta-7,14-diene by (i) contacting 3.beta.-benzoyloxy-cholesta-5,7-diene, in a solvent at a temperature of at most about -55.degree. C., with HCl at a concentration of at least about 2.0 M for a time sufficient to convert the 3.beta.-benzoyloxycholesta-5,7-diene to a 3.beta.-benzoyloxy-5-cholesta-7,14-diene; (ii) neutralizing the resultant reaction mixture with a base to prevent formation of a significant amount of 3.beta.-benzoyloxy-5-cholesta-8,14-diene; and (iii) recovering the 3.beta.-benzoyloxy-5-cholesta-7,14-diene.
一种制备15-氧化类固醇的方法,例如3-β-羟基-5-α-胆甾-8(14)-烯-15-酮,包括将7-去氢胆固醇转化为3-β-苯甲氧基胆甾-5,7-二烯,将3-β-苯甲氧基胆甾-5,7-二烯转化为3-β-苯甲氧基-5-胆甾-7,14-二烯,将3-β-苯甲氧基-5-胆甾-7,14-二烯转化为3-β-苯甲氧基-14-α,15-α-环氧基-5-胆甾-7-烯,然后将3-β-苯甲氧基-14-α,15-α-环氧基-5-胆甾-7-烯转化为15-氧化类固醇。优选地,通过以下步骤将3-β-苯甲氧基-胆甾-5,7-二烯转化为3-β-苯甲氧基-5-胆甾-7,14-二烯:(i)在温度不高于约-55℃的溶剂中,将3-β-苯甲氧基-胆甾-5,7-二烯与至少约2.0 M的HCl接触足够长的时间,将3-β-苯甲氧基胆甾-5,7-二烯转化为3-β-苯甲氧基-5-胆甾-7,14-二烯;(ii)用碱中和所得的反应混合物,以防止显著量的3-β-苯甲氧基-5-胆甾-8,14-二烯的形成;(iii)回收3-β-苯甲氧基-5-胆甾-7,14-二烯。