Therefore the present invention relates specifically to the compounds of general formula (I), in which R1 and R2, which may be identical or different, are selected from the group comprising H, &mdash；CnH2n-1, a linear or branched alkyl group having from 1 to 6 carbon atoms, or together form an aromatic or aliphatic ring with 5 or 6 atoms； R3 is selected from &mdash；CO&mdash；CH3, &mdash；NHOH, &mdash；OH, &mdash；OR6 in which R6 is a linear or branched alkyl group having from 1 to 6 carbon atoms； R4 is selected from H, a linear or branched alkyl group having from 1 to 6 carbon atoms, phenyl, benzyl, &mdash；CF3 or &mdash；CF2CF3, vinyl or allyl； R5, R7, R8 are hydrogen atoms； or R3 and R4, R4 and R5, or R7 and R8 together form a ring, fused to the benzene, aromatic or aliphatic ring with 5 or 6 atoms comprising from 1 to 2 heteroatoms selected independently from the group comprising N, O. and use thereof in the medical field.
