Abstract: The invention relates to compounds of general formula (I): where R1 represents H or a (C1-C4)alkyl, —CO(C1-C4) alkyl, (C1-C4) alkylphenyl or —CO-phenyl group, said phenyl optionally being substituted; R2 represents H, a halogen atom, an —S(O)z(C1-C4)alkyl group, where z is equal to 0, 1 or 2, an —NHSO2(C1-C4)alkyl group, an —NHSO2-phenyl group or an —NHSO2—(C1-C4) alkylphenyl group, said phenyl optionally being substituted; R3 represents an —X—R4 group—in which X represents a bond, an oxygen atom or a —CH2— group and R4 represents H or a —CR5R6—COOR7 group, where R5, R6 and R7 independently represent H or a (C1-C4)alkyl group—a phenyl group optionally substituted or fused with a dioxolane group, a —CO—NR8R9 group—where R8 represents H, a (C1-C4)alkyl group or a (C1-C4)alkyl(C1-C4)alkoxy group and R9 represents a (C1-C4)alkyl(C1-C4)alkoxy group, a —(CH2)n-A group, where n is equal to 0, 1, 2, 3 or 4 and where A represents an indolyl group, a fluorenyl group or a phenyl group which is substituted, an opt