| abstract |
Sterol derivatives of the formula <IMAGE> wherein R1 is a hydrogen atom and R2 is lower alkoxy, or R1 and R2 collectively are lower alkylenedioxy and R3 is a sterol hydrocarbon side chain are converted to the corresponding androsten-17-ones by the oxidative degradation activity of a species of microorganism which degrades sterol side chains, preferably of the genus Mycobacterium. The ether group of those compounds wherein R1 is a hydrogen atom and R2 is lower alkoxy, and the corresponding 17 beta -hydroxy and 17 alpha -hydrocarbon-17 beta -hydroxy compounds is cleaved by reaction with an alkanoic acid chloride or anhydride in the presence of a Lewis acid. |