Studies on the 5β,6β-epoxide opening in withanolides

Abstract

The opening of the steroidal 5β,6β-epoxide group, with or without an adjacent 4β-hydroxy-group, was investigated under thermal conditions on a solid support, and in the presence of sodium chloride for several withanolides. The study was expanded with the compounds being treated with sulphuric acid in acetone at various concentrations and temperatures. Different reaction products (diaxial, diequatorial, or rearranged) were obtained depending on the conditions and the presence or absence of a 2,3-double bond in ring A of these 1-keto-steroids.