The invention relates to a compound of the general formula (I), where: R is a hydrogen atom or a group selected from the (C1-C6)alkyl or (C3-C7)-cycloalkyl groups, optionally substituted by one or more groups independently selected from a halogen atom anti the (C3-C7)-cycloalkyl, (C1-C6)alkyl, (C1-C6)alkoxy, and hydroxy groups； R1 is a phenyl group optionally substituted by one or more substituents independently selected from halogen atoms and the (C1-C6)alkyl, (C1-C6)alkoxy, halo-(C1C6)alkyl, hydroxy, halo-(C1-C6)alkoxy, (C1-C6)alkyl-thio, (C1-C6)alkyl-SO, and (C1-C6)alkyl-SO2 groups； R2 is one or more substituents selected from a hydrogen atom, halogen atoms, and the halo-(C1-C6)alkyl, (C1-C6)alkyl, (C3-C7)cycloalkyl, (C3-C7)-cycloalkyl-(C1C3)alkyl, phenyl, benzyl, (C1-C6)alkoxy, (C1-C6)alkyl-thio, (C1-C6))alkyl-SO, and (C1-C6)alkyl-SO2 groups； and Het is a heteroaryl group； wherein said compound is in the form of a base or an acid addition salt. The invention also relates to the therapeutic use thereof and to a method for synthesising same.
