17-Hydroxy-17-pentafluoroethylestra-4,9 -diene 11-ethynylphenyl derivatives of the formula I in which R 1 is joined to the phenyl ring in the m or p position via a C-C triple bond and is a -(CH=CH) n -R 2, -(CH 2) q -R 3 or -CH=NOR 4 radical, R 2 is hydrogen or an aryl, C 1 -C 10 -alkyl, -CO 2 R 6 or -CN group, R 3 is hydrogen, NH 2, N 3 or an -NHCONHR 4, -OCONHR 4, -OR 5 group, R 4 is selected from the group comprising hydrogen, C 1 -C 10 -alkyl, C 2 -C 10 -alkenyl, aryl, C 7 -C 20 -aralkyl, (CH 2) s -R 6, CH 2 -CO-OR 6, in which R 5 is selected from the group comprising hydrogen, C 7 -C 20 -aralkyl, CH 2 CO 2 R 6, CH 2 CN, CH 2 CH 2 OH, n is 0 to 2, q is 1 or 2, s is 1 or 2, R 6 is hydrogen, C 1 -C 10 -alkyl, aryl, C 7 -C 20 -aralkyl, X is oxygen, NOR 6 or an NNHSO 2 R 6 group where R 6 is as defined above, in which alkyl in R 2, R 4 and R 6 are straight- or branched-chain alkyl groups with the specified number of carbon atoms or, as the case may be, 1-10 carbon atoms, which may have any substitution by perhalogen, hydroxyl groups, C 1 -C 4 -alkoxy groups or C 6 -C 12 -aryl groups (which may in turn be substituted by 1-3 halogen atoms), alkenyl in R 4 are straight- or branched-chain alkenyl groups having 2-10 carbon atoms, which may have any substitution by 1-5 halogen atoms, hydroxyl groups, C 1 -C 3 -alkoxy groups or C 6 -C 12 -aryl groups (which may in turn be substituted by 1-3 halogen atoms), aryl in R 2, R 4 and R 6 are aromatic mono- or bicyclic radicals, for example phenyl or naphthyl, which may have any mono- or polysubstitution by halogen, OH, SO 2 -alkyl, SO-alkyl and S-alkyl, O-alkyl, CO 2 H, CO 2 -alkyl, NH 2, NO 2, N 3, CN, C 1 -C 10 -alkyl, C 1 -C 10 -acyl or C 1 -C 10 -acyloxy groups, aralkyl in R 4, R 5 and R 6 are aralkyl groups in which aralkyl represents aralkyl groups which may contain up to 14 carbon atoms in the ring and 1-8 carbon atoms in the alkyl chain and may have any mono- or polysubstitution by halogen, OH, 0-alkyl, CO 2 H, CO 2 -alkyl, NH 2, NH (C 1 -C 10 -alkyl), N(C 1 -C 10 -alkyl) 2, NO 2, N 3, CN, C 1 -C 20 -alkyl, C 1 -C 10 -perfluoroalkyl, C 1 -C 20 -acyl or C 1 -C 20 -acyloxy groups, and the salts, solvates or solvates of the salts thereof, including all crystal polymorphs, the α-, β- or γ-cyclodextrin clathrates, and the compounds encapsulated with liposomes. R 1 is joined to the phenyl ring in the m or p position via a C-C triple bond and is a -(CH=CH) n -R 2, -(CH 2) q -R 3 or -CH=NOR 4 radical, R 2 is hydrogen or an aryl, C 1 -C 10 -alkyl, -CO 2 R 6 or -CN group, R 3 is hydrogen, NH 2, N 3 or an -NHCONHR 4, -OCONHR 4, -OR 5 group, R 4 is selected from the group comprising hydrogen, C 1 -C 10 -alkyl, C 2 -C 10 -alkenyl, aryl, C 7 -C 20 -aralkyl, (CH 2) s -R 6, CH 2 -CO-OR 6, in which R 5 is selected from the group comprising hydrogen, C 7 -C 20 -aralkyl, CH 2 CO 2 R 6, CH 2 CN, CH 2 CH 2 OH, n is 0 to 2, q is 1 or 2, s is 1 or 2, R 6 is hydrogen, C 1 -C 10 -alkyl, aryl, C 7 -C 20 -aralkyl, X is oxygen, NOR 6 or an NNHSO 2 R 6 group where R 6 is as defined above, in which alkyl in R 2, R 4 and R 6 are straight- or branched-chain alkyl groups with the specified number of carbon atoms or, as the case may be, 1-10 carbon atoms, which may have any substitution by perhalogen, hydroxyl groups, C 1 -C 4 -alkoxy groups or C 6 -C 12 -aryl groups (which may in turn be substituted by 1-3 halogen atoms), alkenyl in R 4 are straight- or branched-chain alkenyl groups having 2-10 carbon atoms, which may have any substitution by 1-5 halogen atoms, hydroxyl groups, C 1 -C 3 -alkoxy groups or C 6 -C 12 -aryl groups (which may in turn be substituted by 1-3 halogen atoms), aryl in R 2, R 4 and R 6 are aromatic mono- or bicyclic radicals, for example phenyl or naphthyl, which may have any mono- or polysubstitution by halogen, OH, SO 2 -alkyl, SO-alkyl and S-alkyl, O-alkyl, CO 2 H, CO 2 -alkyl, NH 2, NO 2, N 3, CN, C 1 -C 10 -alkyl, C 1 -C 10 -acyl or C 1 -C 10 -acyloxy groups, aralkyl in R 4, R 5 and R 6 are aralkyl groups in which aralkyl represents aralkyl groups which may contain up to 14 carbon atoms in the ring and 1-8 carbon atoms in the alkyl chain and may have any mono- or polysubstitution by halogen, OH, 0-alkyl, CO 2 H, CO 2 -alkyl, NH 2, NH (C 1 -C 10 -alkyl), N(C 1 -C 10 -alkyl) 2, NO 2, N 3, CN, C 1 -C 20 -alkyl, C 1 -C 10 -perfluoroalkyl, C 1 -C 20 -acyl or C 1 -C 20 -acyloxy groups, and the salts, solvates or solvates of the salts thereof, including all crystal polymorphs, the α-, β- or γ-cyclodextrin clathrates, and the compounds encapsulated with liposomes.