Process for the preparation of polyhalosteroids

摘要

9 alpha ,21-dihalo-11 beta ,17 alpha -dihydroxy-6 alpha -fluoro-16 alpha -methylpregna-1,4-diene -3,20-dione 17-esters of the formula in which X is chlorine or fluorine, X' is bromine or chlorine, and Ac is an acyl group derived from a carboxylic acid, are distinguished by high local antiinflammatory activity with a reduced systemic effect, for which reason they can be used in medicine to alleviate and control inflammatory states. They are prepared by conventional epoxide ring opening from the corresponding 9 beta ,11 beta -oxido starting material with hydrogen halide HX.