Refers to compounds derived from acid - 3 - pyrrolidin-3-yl ilacetico formula (1) wherein R is alkyl, cycloalkyl (C1 - C6) (C3 - C8) or cicloalquenilo (C3 - C8) X is alkyl (C1 - C6) Z and y are each Halogen or alkyl (C1 - C6) n is 0 OR 1.Preferred compounds are: acid, 2 - [(3S, 4R) - 1 - {[2 - Chloro - 5 - (trifluoromethyl) phenyl] methyl} {- 3 - [1 - (2 - fluoropentil) piperidin-4-yl] carbamoyl IL - metilpirrolidin} - 4 - 3 - 2 il] acetic acid - [(3S, 4R) - 1 - [(2,6-dichlorophenyl) methyl] - 3 - ({1 - [(4,4 - difluorociclohexil piperidin-4-yl) methyl] Il} Carbamoyl) - 4 - metilpirrolidin - 3 - il] Cetico, among others. It also relates to a Pharmaceutical composition.These compounds have an inhibiting effect on the route fractalcina - CX3CR1 being useful in the treatment of ulcerative colitis, Crohns diseaseSE REFIERE A COMPUESTOS DERIVADOS DE ACIDO PIRROLIDIN-3-ILACETICO DE FORMULA (1) DONDE R ES ALQUILO(C1-C6), CICLOALQUILO(C3-C8) O CICLOALQUENILO(C3-C8) X ES ALQUILO(C1-C6) Z E Y SON CADA UNO HALOGENO O ALQUILO(C1-C6) n ES 0 O 1. SON COMPUESTOS PREFERIDOS: ACIDO 2-[(3S,4R)-1-{[2-CLORO-6-(TRIFLUOROMETIL)FENIL]METIL}-3-{[1-(2-FLUOROPENTIL)PIPERIDIN-4-IL]CARBAMOIL}-4-METILPIRROLIDIN-3-IL]ACETICO ACIDO 2-[(3S,4R)-1-[(2,6-DICLOROFENIL)METIL]-3-({1-[(4,4-DIFLUOROCICLOHEXIL)METIL]PIPERIDIN-4-IL}CARBAMOIL)-4-METILPIRROLIDIN-3-IL]ACETICO ENTRE OTROS. TAMBIEN SE REFIERE A UNA COMPOSICION FARMACEUTICA. DICHOS COMPUESTOS TIENEN UN EFECTO INHIBIDOR EN LA RUTA DE FRACTALCINA-CX3CR1 SIENDO UTILES EN EL TRATAMIENTO DE COLITIS ULCEROSA, ENFERMEDAD DE CROHN