Epoxides of lanosterol and some related compounds

Abstract

A convenient method for the separation of the two isomers of 24ξ,25-epoxy-5α-lanost-8-en-3β-yl acetate is described. The absolute configuration of these compounds is established by their conversion into the corresponding 5α-lanost-8-ene-3β,24ξ-diol 3-acetates, and thence by Horeau's method (treatment with α-phenylbutyric anhydride), and by the method of molecular rotation differences. A number of related compounds have also been prepared and their absolute configurations determined by correlation with the above compounds.