Pyridazinone compounds and their use as inhibitors DAAO

A compound of formula (I) ** ** Formula wherein R1 represents a hydrogen atom or fluorine atom or a trifluoromethyl group; R represents a group -X-Y-R3; X and Y each independently represent a bond, an oxygen atom or a -C (O), -S (O) n, - C (O) NR4, -S (O) 2NR4, -NR4, or -CR4R5 -, provided that X and Y can not both simultaneously represent a bond and provided that if X and Y are both other than a bond, then at least one of X and Y represents -CR4R5-; n is 0, 1 or 2; each R 4 independently represents a hydrogen atom or a C1-C6 alkyl or C1-C6 haloalkyl group; each R5 independently represents a hydrogen atom, a C1-C6 alkyl or haloalkyl group or C1-C6> = CH-; R3 represents a carbocyclic or heterocyclic ring saturated or unsaturated 3 to 10 members, the system itself ring optionally substituted by at least one substituent selected from halogen, hydroxyl, cyano, oxo, C1-C6 alkyl, alkenyl being C2-C6 , C1-C6 haloalkyl, C1-C6 hydroxyalkyl, C1- C6 alkoxy, C1-C6 haloalkoxy, C1-C6 alkylthio, C1-C6-alkylsulfinyl, C1-C6alkylsulfonyl, C1-C6-alkylcarbonyl, C1- C6-alkylcarbonyloxy, C1-C6-alkylcarbonyl, amino (-NH2), -CON (R6) 2, C1-C6-alkylamino, di- (C1-C6) amino, C3-C6 cycloalkyl, C3-C6 cycloalkyloxy , C3-C6-methyl, - [O] p- (CH2) qO-R7 and a saturated or unsaturated 4 to 6-membered heterocyclic ring (optionally substituted by at least one substituent selected from C1-C4 alkyl and C1- alkoxy C4); each R6 independently represents a hydrogen atom or a C1-C6 alkyl; p is 0 or 1; q is 1, 2, 3 or 4; and R 7 represents a group C1-C6 alkyl; or a pharmaceutically acceptable salt thereof.