. . . . "R13 represents a hydrogen atom, a C1-C4 alkoxy radical, a halogen atom such as bromine, chlorine, iodine or fluorine, or an amino radical, R14 represents a hydrogen atom, a C1-C4 alkyl radical or forms, with a carbon atom of the benzene ring, a heterocycle optionally having oxygen and/or substituted with at least one C1-C4 alkyl group, R15 represents a hydrogen atom or a halogen atom such as bromi" .