Pure 17 alpha-ethynyl(5 alpha), androst-2-ene,17 beta-cl, process for its preparation and therapeutical applications of the same

The delta-2 isomer of the 17 alpha-ethynyl (5 alpha), 2-androsten, 17 beta-ol, unmixed with its delta-3 isomer; a process for making the therapeutic isomer and its 17 beta-acetate; and a method of treatment of endometriosis with the 17 beta-acetate of the delta-2 isomer. The pure delta-2 isomer of 17 alpha-ethynyl (5 alpha), 2-androsten, 17 beta-ol, unmixed with its delta-3 isomer, is obtained by oxidation of the isomeric precursor 17-keto (5 alpha), 2-androsten with Jones Reagent. The 17 beta-acetate of the delta-2 isomer of the beta-ol is effective in the treatment of endometriosis by the administration of a daily dose of about 100 to 300 milligrams.