2β,19-Epoxy-5α-cholestane, readily obtained from 5α-cholestan-2β-ol by treatment with lead tetra-acetate, on acetolysis with acetic anhydride catalysed by pyridinium hydrochloride or by boron trifluoride gave a variety of products, from which were derived 5α-cholestan-19-oic acids, 5α-cholest-1- and -2-en-19-aldehydes, and 5α-cholestan-19-ols. 2α-Acetoxy- and 2α-methoxy-5α-cholestan-19-oic acids resisted
通过用四
乙酸铅处理,在
盐酸吡啶鎓或
三氟化硼催化下用
乙酸酐乙酰化,从
5α-胆甾烷2β-醇中容易获得2β,19-环氧
5α-胆甾烷,得到了多种产品,衍生5α-cholestan-19-oic酸,5α-cholestan-19和-2-en-1
9-醛以及5α-cholestan-19-ols。2α-乙酰氧基-和2α-甲氧基-
5α-胆甾烷-19-
油酸抗脱羧;对5α-胆甾-1-和2-en-19-als的不可分离混合物进行脱羰,得到19-nor-5α-胆甾-1-烯。