A compound of the formula (I): ** Formula ** in which R1 is a phenyl group； R2 is a linear or branched hydrogen atom or C1-C6 alkyl； R3 is an aryl group； R4 is a hydrogen atom； R5 and R7 are each independently a hydrogen or halogen atom； R6 is a hydrogen atom, a halogen or a C1-C6 alkyl group； in which the aryl groups are carbocyclic or heterocyclic groups containing one or two ring fractions, fused or linked together by simple bonds, in which at least one of the rings is aromatic； where appropriate, any aromatic heterocyclic ring, also called a heteroaryl group, comprises a five to six membered ring with one to three heteroatoms selected from N, NH, O or S； and in which the linear or branched aryl, phenyl and C1-C6 alkyl groups may be optionally substituted in any of their free positions with one or more groups independently selected from: halogen atom, nitro groups, oxo (>； = O), cyano , C1-C6 alkyl, polyfluorinated alkyl, polyfluorinated alkoxy, alkenyl, alkynyl, hydroxyalkyl, aryl, arylalkyl, heterocyclyl, C3-C6 cycloalkyl, hydroxy, alkoxy, aryloxy, heterocyclyloxy, methylenedioxy, alkylcarbonyloxy, arylcarbonyloxy, cycloalkenyloxy, heterocyclylcarbonyloxy, alkylideneaminoxy, carboxy , alkoxycarbonyl, aryloxycarbonyl, cycloalkyloxycarbonyl, loxicarbonilo, heterocyclic, amino, ureido, alkylamino, dialkylamino, arylamino, diarylamino heterocyclylamino, formylamino, alkylcarbonylamino, arylcarbonylamino, heterocyclic-carbonylamino, aminocarbonyl, alkylaminocarbonyl, dialkylaminocarbonyl, arylaminocarbonyl, heterocyclyl aminocarbonyl, alkoxycarbonylamino, hydroxyaminocarbonyl alkoxyimino al chylsulfonylamino, arylsulfonylamino, heterocyclylsulfonylamino, formyl, alkylcarbonyl, arylcarbonyl, cycloalkylcarbonyl, heterocyclylcarbonyl, alkylsulfonyl, arylsulfonyl, aminosulfonyl, alkylaminosulfonyl, dialkylaminosulfonyl, arylamino-sulfonylophonylophonylophonylophonylalkyl, alkylarylthiophonylophonyloonylophonylalkyl, alkylarylphosphonylalkyl； provided that the 1-methyl
