The invention relates to 17-hydroxy-17-pentafluoroethane-estra-4, 9 (10) - dien-11-formula (I) derivative,Their stereoisomers, salts, solutions, salt solutions, wherein: R1 is an excimer or a monophenyl ring, or dissolved with y; Sr2, s (o) R3, among others; R2 is h, C1-C6 tar; R3 is C1-C6 or arilo tar; X is O, nro7 or nnhso2r7; R7 is h, C1-C10 tar or arilo. The favorite compound is notes17? -17-hydroxy-11 - [4 - (methylsulfur) phenyl] - 17 - (pentafluoroethane) est-4, 9-dien-3-ona; (11? notes17? -11 - [4 - (ethylsulfonamide) phenyl] - 17-hydroxy-17 - (pentafluoroethane) est-4, 9-dien-3-one; These compounds have antagonistic effects on progesterone, and are useful in the treatment or prevention of uterine cellulose, uterine endocrine, etc.La presente invencion se refiere a derivados de 17-hidroxi-17-pentafluoroetil-estra-4,9(10)-dien-11-arilo de formula (I), sus estereoisomeros, sales, solvatos, solvatos de las sales, en donde: R1 es un radical Y o un anillo fenilo mono- o disustituido con Y; Y es SR2, S(O)R3, entre otros; R2 es H, alquilo C1-C6, entre otros; R3 es alquilo C1-C6 o arilo; X es O, NRO7 o NNHSO2R7; R7 es H, alquilo C1-C10 o arilo. Son compuestos preferidos: (11?, 17?)-17-hidroxi-11-[4-(metilsulfanil)fenil]-17-(pentafluoroetil)estra-4,9-dien-3-ona; (11?, 17?)-11-[4-(etilsulfanil)fenil]-17-hidroxi-17-(pentafluoroetil)estra-4,9-dien-3-ona; entre otros. Estos compuestos tienen accion antagonista de progesterona siendo utiles en el tratamiento o prevencion de fibroides uterinos, endometriosis, entre otros