To 100 ml of 30% aqueous acetone are added 1.0 g of myristic acid and 0.8 g of potassium carbonate, followed by addition of 1.16 g of 16β-ethyl-17β-bromoacetoxy-4-estren-3-one. The mixture is refluxed for 5 hours. After cooling, the reaction mixture is extracted with 150 ml of ethyl acetate. The organic layer is separated, washed with water and saturated aqueous sodium chloride solution and dried over anhydrous sodium sulfate. The solvent is then distilled off under reduced pressure and the residue is subjected to column chromatography, elution being carried out with 600 ml of toluene-diisopropyl ether (19:1). The eluate is evaporated under reduced pressure to remove the solvent, giving a light-yellow viscous oil. This product is allowed to stand at room temperature (15°-25° C.) to give 1.0 g of the above-identified compound as a solid.
