Patent ID: 7582797

Claim:
Compound characterized in that it corresponds to formula (1) in which each group R 1 is identical to the other group R 1 and represents: a C 1 to C 6 alkyl, C 2 to C 6 alkenyl or C 2 to C 6 alkynyl group, a (CH 2 ) n benzyl group in which n is equal to 0 or 1, a (CH 2 ) m (C 3 to C 6 cycloalkyl) group in which m is equal to 0 or 1, each of the alkyl, alkenyl, alkynyl, benzyl or cycloalkyl groups being substituted with one or two group(s) represented by the group A; the group A represents: a carboxylate group COOH or COOR, R representing a C 1 to C 6 alkyl or CH 2 phenyl group; a sulfonate group SO 3 H or SO 3 R′, R′ representing a C 1 to C 6 alkyl or CH 2 phenyl group; a phosphonate group PO 3 H 2 or PO 3 R 2 ″R′″, R″ and R′″ independently representing H, or a C 1 to C 6 alkyl or CH 2 phenyl group; each group R 2 is identical to the other group R 2 and represents a C 1 to C 6 alkyl, C 2 to C 6 alkenyl or C 2 to C 6 alkynyl group, each alkyl, alkenyl or alkynyl group being free or substituted with the group B; the group B represents: a carboxylate group, COOH or COOR′, R′ representing a C 1 to C 6 alkyl or CH 2 phenyl group; a phenyl group that is free or substituted with one or more radicals chosen from a halogen atom, an optionally protected hydroxyl radical, a C 1 to C 4 alkyl group, a cyano group, a free, salified or esterified carboxyl group or an amide group; each group R 3 is identical to the other group R 3 and represents a hydrogen atom.