64.8 g of trimethylsulfoxonium iodide is dissolved in 900 ml of dimethyl sulfoxide under nitrogen atmosphere with stirring and to this solution 27.55 g of potassium hydroxide is added at 25-30° C. The reaction mixture is stirred for 1 hour, then 81.1 g of 15α-acetoxy-3-methoxy-androst-3,5-diene-17-one is added and stirring is continued at 25-30° C. until the reaction is finished (about additional 6 hours). The solution is slowly added to 4500 ml of water, the precipitate is compacted by stirring (30 minutes), filtered, washed with water until it is neutral and dried in vacuo to constant weight below 40° C. The title compound is crystallized from methanol.
