Synthesis of Polyhydroxysteroids. I. A Modified Degradation of the Diosgenin Side Chain

Chlorination of diosgenin acetate followed by treatment with performic acid, dechlorination, and hydrolysis has given pregn-5-ene-3β, 16β, 20α-triol in 60∼70% overall yield. When the chlorination was conducted in a dimethylformamide solution, the main product was 3β-acetoxy-5-chloro-6β-formyloxy-5α, 25D-spirostan. Validity of this novel reaction was confirmed by expriments in the cholesterol series. Synthesis of 9α-chloro-11β-formyloxysteroids from l9(11)-steroids has also been facilitated.