Patent ID: 7807708

Claim:
A ligand compound having the formula (I) below: in which: R 1 is a hydrogen atom, an alkyl radical of 1 to 4 carbon atoms or a —CF 3 radical; R 2 is a hydrogen atom, an alkyl or alkoxy radical of 1 to 4 carbon atoms or a chlorine atom; R 3 is a hydrogen atom or a linear or branched alkyl or alkoxy radical of 1 to 10 carbon atoms optionally substituted with a methoxy group; R 4 is a hydrogen atom or an alkyl radical of 1 to 3 carbon atoms; R 5 is a hydrogen atom or an alkyl radical of 1 to 3 carbon atoms; or alternatively R 4 and R 5 form, together with the bond —N—C(═Y)—, a pyrrolidine, pyrrolidinone, piperidine or piperidinone ring; Y is two hydrogen atoms or a hetero atom; Ar is a 1,4-phenyl, 2,5-pyridyl, 5,2-pyridyl or 2,5-thiophenyl ring; X is an oxygen atom optionally substituted with an alkyl or alkylamine radical or a C—C single bond; A is a hydrogen atom or the following formula: in which, Q is an oxygen atom or an —NH— bond; R 6 is a hydrogen atom, an alkyl radical of 1 to 6 carbon atoms, a cycloalkyl radical of 3 to 6 carbon atoms or a —C(O)CH 3 or —C(O)CH 2 CH 3 radical; R 7 and R 7 ′ represent, independently of each other, a hydrogen atom or a hydroxyl group, with the provisio that R 7 and R 7 ′ are not simultaneously a hydroxyl group; n is 0, 1, 2, 3, 4 or 5; and the salts of the compounds of formula (I) when R 3 is a hydrogen atom and also the geometrical isomers of the said compounds of formula (I).