Patent ID: 8519139

Claim:
A compound of formula (II): wherein X is an NHC(O) or C(O)NH group, R3 and R4, which may be identical or different, are a hydrogen or halogen atom, or an amino, nitro, hydroxyl, linear or branched C 1-3 alkyl, C 1-3 alkoxy, di(C 1-3 )alkylamino, acetylamino or phenyl-(C 1-3 )alkoxy group, or R3 and R4, together, form a 5- to 7-membered ring in which one or two of the said members may be a hetero atom selected from the group consisting of N, S and O, and R5, R6, R7 and R8, which may be identical or different, are H or methyl.