14, 15-cis Glycols derived from Digitoxigenin

Abstract

Treatment of β-anhydrodigitoxigenin acetate (I) with osmium tetroxide gave two cis-glycols (β- and α-), 15β-hydroxydigitoxigenin 3-monoacetate (II) and 15α-hydroxy-14α-digitoxigenin 3-monoacetate (IV) in the ratio of approximately 1 : 9. Acid hydrolysis of II and IV yielded 15β-hydroxydigitoxigenin (III) and 15α-hydroxy-14α-digitoxigenin (V). On the other hand, treatment of β-anhydro-17α-digitoxigenin (β-anhydromenabegenin) (X) as well as its acetate (IX) with the reagent resulted exclusively in the formation of the β-glycol, 15β-hydroxy-17α-digitoxigenin (15β-hydroxymenabegenin) (XII) and its 3-monoacetate (XI) respectively.