Referring to a pyridazine hydrochloride derivative Compound of formula (i), where X1 - X2 is CH - ch - ch - ch, N OR N and is n, CH or COH r1 is Halo or c1-c6 alkyl R2 and R3 are h, Methyl, Ethyl, Isopropyl, ciclopropilo or metoximetilo R4 it is alcanoilo c1-c6 alkyl, alkoxy C1 - C2 - C6, c6alquilo C1 - C6, among others R5 is Oxo, Methyl, Ethyl, Isopropyl, ciclopropilo or metoximetilo K and P is 0, 1 or 2 M is 1, 2,3 or 4 n is 1 or 2.Preferred compounds are: 6 - (4 - (4 - [3 - (4 - acetilpiperazin - 1 - il) propoxy] phenyl] piperazin-1-yl) - 3 - (trifluoro methyl) [1,2,4] triazolo [4,3-b] pyridazine hydrochloride, 1 - methyl - 4 - [2 - (4 - {1 - [3 - (Methyl trifluoro - [1,2,4] triazolo [4,3-b] pyridazin-3 - il 6 il} piperidin-4-yl] phenoxy) ethyl] - 2 - piperazin Ona, 4 - [2 - (4 - (4 - hydroxy - 3 - [1 - (trifluoro Methyl) - [1,2,4] triazolo [4,3-b] pyridazin-3 - il 6 il} piperidin-4-yl] phenoxy) ethyl] - 1 - 2 - metilpiperazin onaAmong others. It also relates to a Pharmaceutical Composition and a preparation method. These compounds act as ligands of the androgen receptor (AR) and are useful in the treatment of Prostate CancerREFERIDA A UN COMPUESTO DERIVADO DE PIRIDAZINA DE FORMULA (I), DONDE X1-X2 ES CH-CH, N-CH O CH-N Y ES N, CH O COH R1 ES HALO O ALQUILO C1-C6 R2 Y R3 SON H, METILO, ETILO, ISOPROPILO, CICLOPROPILO O METOXIMETILO R4 ES ALQUILO C1-C6, ALCANOILO C2-C6, ALCOXI C1-C6ALQUILO C1-C6, ENTRE OTROS R5 ES OXO, METILO, ETILO, ISOPROPILO, CICLOPROPILO O METOXIMETILO k Y p SON 0, 1 O 2 m ES 1, 2, 3 O 4 n ES 1 O 2. SON COMPUESTOS PREFERIDOS: 6-(4-{4-[3-(4-ACETILPIPERAZIN-1-IL)PROPOXI]FENIL}PIPERAZIN-1-IL)-3-(TRIFLUORO-METIL)[1,2,4]TRIAZOLO[4,3-b]PIRIDAZINA, 1-METIL-4-[2-(4-{1-[3-(TRIFLUORO-METIL)[1,2,4]TRIAZOLO[4,3-b]PIRIDAZIN-6-IL]PIPERIDIN-4-IL}FENOXI)ETIL]PIPERAZIN-2-ONA, 4-[2-(4-{4-HIDROXI-1-[3-(TRIFLUORO-METIL)[1,2,4]TRIAZOLO[4,3-b]PIRIDAZIN-6-IL]PIPERIDIN-4-IL}FENOXI)ETIL]-1-METILPIPERAZIN-2-ONA, ENTRE OTROS. TAMBIEN ESTA REFERIDA A UNA COMPOSICION FARM
