Abstract The title compound (4) was prepared starting from 17β, 19-dihydroxyandrosta-4, 6- dien-3-one 17, 19-diacetate (5). Copper-catalyzed conjugate addition of methylmagnesium iodide gave, after hydrolysis, 17β, 19-dihydroxy-7α-methylandrost-4-en-3-one (8a), which was converted by oxidation and deacylation into 7α-methylestr-5 (10)-ene-3, 17-dione (11). Selective protection of the 3-keto group as the dimethyl acetal, followed by ethynylation ...