Thiosteroids. XXVI. Steroidal Transannular 2, 5-Epoxide and Related Compounds

Abstract

A number of 3α-substituted (H, OH, OAc or SCN)-2β, 5α-dihydroxycholestanes upon treatment with mesyl chloride and pyridine gave the corresponding 2α, 5α-epoxides. These structures were established by the nuclear magnetic resonance spectra and by chemical conversions. In addition, the reaction of a series of 5α-hydroxy-2α, 3α-epoxysteroids with hydrobromic acid leading to the 3α-hydroxy-2α, 5α-epoxysteroids was studied. The reaction mechanism was also discussed.