(3alpha,5beta,20S)-Pregnane-3,17,20,21-tetrol 20alpha-Hexahydro-reichstein's compound S 3615-89-2 5beta-Pregnane-3alpha,17alpha,20alpha,21-tetrol 5beta-Pregnane-3alpha,17alpha,20beta,21-tetrol Pregnane-3,17,20,21-tetrol, (3alpha,5beta,20S)-