3-beta-hydroxy-5-beta-cardenolides

摘要

14 beta- or 14-dehydro-3 beta-hydroxy-5-beta-cardenolides are prepd. by a Meerwein-Penndorf reduction of the 3-keto derivs. and opt. sepg. the 3 alpha-hydroxy compds. which may be oxidised to give the 3-keto starting materials. Reduction yields 50% each of the 3 alpha- and 3 beta-isomers and the 3 alpha-isomer is oxidised to the 3-keto deriv. in 85% yield.