GB710557A - Steroid compounds - Google Patents

Abstract

The invention comprises a process of reacting a 17(a ) - hydroxy - 3,20 - diketo pregnane compound with bromine to obtain the 4-bromo-derivative and heating the 4-bromo-derivative with pyridine to produce the corresponding D 4 - 17(a ) - hydroxy - 3,20 - diketo - pregnene compound. The compound reacted with the bromine to yield the 4-bromo derivative may have the formula <FORM:0710557/IV (b)/1> wherein R1 is an acyloxy radical or hydrogen and R2 is a keto radical or hydrogen, the compound produced by heating the 4-bromo-derivative being the corresponding D 4-pregnene derivative. In examples: (1) 3,11,20-triketo-17(a )-hydroxy-pregnane is reacted with bromine in acetic acid to give 4-bromo-3,11,20-triketo-17(a )-hydroxy-pregnane, which on refluxing with pyridine yields D 4-3,11,20-triketo-17(a )-hydroxy-pregnene; (2) 3,11,20-triketo-17(a )-hydroxy - 21 - acetoxy - pregnane is reacted with bromine in acetic acid to give 4-bromo-3,11,20 - triketo - 17(a ) - hydroxy - 21 - acetoxy - pregnane which on refluxing with pyridine yields D 4 - 3,11,20 - triketo - 17(a ) - hydroxy - 21 - acetoxy - pregnene. (Kendall's compound E acetate). The preparation of the 17(a ) - hydroxy - 3,20 - diketo - pregnanes used as starting materials is described, as in Specification 710,482. The 3,11,20 triketo - 17(a ) - hydroxy 21 - acetoxy pregnane employed in (2) is prepared by reacting the 21-hydroxy-compound with acetic anhydride.