Derivatives of 2-pyridin-2-yl-pyrazol-3(2H)-one, preparation and therapeutic use thereof as HIF activators

A compound of formula (I):

• wherein
• R represents —SO2—NR3R4 or —SO2—R4;
• R3 and R4 being as defined below;
• R1 represents —W-aryl, the said aryl being optionally substituted on at least one carbon atom with at least one substituent chosen from halogen, (C1-C5)alkyl, —(C1-C5)alkylene-O—(C1-C5)alkyl, —(C1-C5)alkoxy, hydroxy, -halo(C1-C5)alkyl, cyano, —O(C1-C5)alkylene-O—(C1-C5)alkyl, —O—(C1-C5)alkylene-NR5R6, —SO2—(C1-C5)alkyl, —NR5R6 and —CO2R5,
• R2 represents hydrogen, —(C1-C5)alkyl, —(C1-C5)alkylene-O—(C1-C5)alkyl, -halo(C1-C5)alkyl, —W—COOR5, —W—C(O)NHR5 or —W—C(O)—NR5R6;
• W, R5 and R6 being as defined below;
• it being understood that:
• n represents 0, 1 or 2;
• W is
• (i) —(C1-C5)alkylene-, optionally substituted with a group chosen from —(CH2)n-CO2R5 and —(CH2)n-(CO)NR5R6, with n as defined above and R5 and R6 as defined below;
• or
• (ii) —(C3-C6)cycloalkylene-,
• R3 and R4 which may be identical or different, represent, independently of each other, hydrogen, —(C1-C5)alkyl, —(C3-C6)cycloalkyl, —(C1-C5)alkylene-O—(C1-C5)alkyl, aryl, —CH2-aryl, —W—OH, —W—CHOH—CH2OH, —W—CO2R5, —W—NR5R6 or —W—O—(CH2)n-aryl;
• the said —(C3-C6)cycloalkyl being optionally substituted
• on at least one carbon atom with at least one group chosen from —(C1-C5)alkyl, —(C1-C5)alkoxy, hydroxy, —W—NR5R6 and —W—CO2R5,
• with W and n as defined previously and R5 and R6 as defined below and provided that when R3 and R4 are identical, they cannot be hydrogen;
• and
• R5 and R6, which may be identical or different, represent, independently of each other, hydrogen, —(C1-C5)alkyl or —(C1-C5)haloalkyl,
• in the form of the base or an acid-addition salt.