Verfahren zur Herstellung von ungesättigten 6-Halogen-3-keto-steroiden

The invention comprises a process for the preparation of steroids of the general formula wherein X represents fluorine, chlorine or bromine, R1 represents O, H,H, or H, OR3(a -or b -), R2 represents R3 represents H or acyl, and R4 represents H or OR3 in which R3 has the significance previously indicated and wherein said steroid compounds may contain a further double bond in the 1(2)-position, by treating steroids of the general formula wherein R1, R2, R3 and R4 have the above significance, with a per-acid to form the corresponding 6a ,7a -epoxides, treating the epoxides with the required hydrohalic acids to form the corresponding 6-halo-7-hydroxy-steroids, and treating the 6-halo-7-hydroxy-steroids with a dehydrating agent and, if desired, treating the products with saponifying reagents and/or converting them into physiologically well tolerated esters. The invention also includes the steroids of the first general formula above, wherein R1, R2 and X have the above significance and which may contain a further double bond in the 1,2-position, except those compounds wherein X represents chlorine or bromine, R1 represents O or H, OH and R2 represents The saponifying reagents used in the above process may be acid or alkaline reagents or the saponification may be carried out by microbiological means such as by the action of Flavobacterium dehydrogenans. Steroids of the first general formula above having a free 21-hydroxy group may be 21-esterified, e.g. with carboxylic, phosphoric and sulphuric acids. The D 1,4,6-steroids of the first general formula may also be prepared by dehydrogenating the corresponding D 4,6-steroids, e.g. with selenium dioxide. Steroids of the general formula p wherein R1, R2, R3 and R4 have the above significance, are prepared by dehydrogenating the corresponding D 4-steroids with chloranil to form the D 4,6-steroids. The corresponding D 1,4,6-steroids may be obtained by dehydrogenating the D 4,6-steroids with chemical or microbiological dehydrogenating agents such as selenium dioxide or Bacillus sphaericus. Specifications 878,743, 890,835, 895,842 and 896,986 are referred to.