Styrl tetrahydroquinolinium thiol/disulfide dye compound and method for lightening keratin materials using the same

A fluorescent dye of formula (I) or (II):

• the organic or mineral acid salts thereof, optical isomers and geometric isomers thereof, or the solvates thereof:
• wherein:
• is chosen from an aryl, a heterocyclic, and a heteroaryl group fused to the phenyl ring;
• or is absent from the phenyl ring;
• G and G′, which may be identical or different, are chosen from an —NRcRd group and a (C1-C6)alkoxy group, which is optionally substituted;
• or G or G′ is absent;
• Rc and Rd, which may be identical or different, are chosen from a hydrogen atom, an optionally substituted (C1-C6)alkyl group, an aryl(C1-C4)alkyl group, and a (C1-C6)alkoxy(C1-C6)alkyl group;
• or the two Rc and Rd radicals may form, together with the nitrogen atoms to which they are attached, a heterocyclic or heteroaryl group;
• Rg, R′g, R″g, R′″g, Rh, and R′″h, which may be identical or different, are chosen from a hydrogen atom, a halogen atom, an amino, a (di)(C1-C4)alkylamino, a cyano, a carboxyl, a hydroxyl, a trifluoromethyl, a acylamino, a C1-C4 alkoxy, a C2-C4 (poly)hydroxyalkoxy, a (C1-C4)alkylcarbonyloxy, a (C1-C4)alkoxycarbonyl, a (C1-C4)alkylcarbonylamino, a acylamino, a carbamoyl, a (C1-C4)alkylsulfonylamino group, an aminosulfonyl radical, and a (C1-C16)alkyl radical optionally substituted with a group chosen from (C1-C12)alkoxy, hydroxyl, cyano, carboxyl, amino, and (di)(C1-C4)alkylamino wherein optionally the two alkyl radicals borne by the nitrogen atom of the amino group form a heterocycle comprising from 5 to 7 members and optionally comprising another heteroatom identical to or different from that of the nitrogen atom;
• or two groups Rg and R′g, or R″g and R′″g, together with the two adjacent carbon atoms to which they are attached, form a benzo, an indeno ring, a fused heterocycloalkyl, or a fused heteroaryl group;
• wherein the benzo, indeno, heterocycloalkyl, or heteroaryl ring being optionally substituted with at least one radical chosen from a halogen atom, a (C1-C4)alkyl, an amino, a (C1-C4)alkylamino, a (C1-C4)dialkylamino, a cyano, a carboxyl, a hydroxyl, a trifluoromethyl group, an acylamino, a C1-C4 alkoxy, a C2-C4 (poly)hydroxyalkoxy, a alkylcarbonyloxy, a alkoxycarbonyl, a alkylcarbonylamino, an acylamino, a carbamoyl, a alkylsulfonylamino radical, an aminosulfonyl radical, and a (C1-C16) alkyl radical optionally substituted with a group chosen from (C1-C12)alkoxy, hydroxyl, cyano, carboxyl, amino, (C1-C4)alkylamino, (C1-C4) dialkylamino, and (C1-C4) dialkylamino wherein the two alkyl radicals borne by the nitrogen atom of the amino group form a heterocycle comprising from 5 to 7 members and optionally comprising another heteroatom identical to or different from that of the nitrogen atom;
• or when G and/or G′ are —NRcRd, two groups Rc and R′g, Rd and Rg, and/or Rc and R″g, Rd and R′″g together form a saturated heteroaryl or heterocycle, optionally substituted with at least one (C1-C6)alkyl group;
• R′i and R′″i, which may be identical or different, are chosen from a hydrogen atom and a (C1-C4)alkyl group;
• R′h with R″i and R″h with R′″i form, together with the carbon atoms which bear them, an optionally substituted C5-C7 cycloalkyl group fused to the pyridinium group, wherein the R′h or R″h radical and the styryl group bearing the R′i or R′″i radical are positioned on adjacent carbon atoms of the pyridinium groups;
• R1, R2, R3, R4, R′1, R′2, R′3, and R′4, which may be identical or different, are chosen from:
• a hydrogen atom,
• a (C1-C4)alkyl group,
• a (C1-C12)alkoxy,
• a hydroxyl,
• a cyano,
• a —C(O)O−M+ wherein M+ is an alkali metal or M+ and An− are absent,
• a carboxyl,
• a (di)(C1-C4)(alkyl)amino, wherein the two alkyl radicals may optionally form, with the nitrogen atom which bears them, a heterocycle comprising from 5 to 7 members, optionally comprising another heteroatom which may or may not be different from nitrogen;
• Ta and Tb, which may be identical or different, are chosen from:
• i) a σ covalent bond;
• ii) at least one radical or combination thereof, chosen from —SO2—, —O—, —S—, —N(R)—, —N+(R)(Ro)—, and —C(O)—, wherein R and Ro, which may be identical or different, are chosen from a hydrogen atom, a C1-C4 alkyl radical, a C1-C4 hydroxyalkyl radical, and an aryl(C1-C4)alkyl;
• and
• (iii) a monocyclic, cationic or noncationic, heterocycloalkyl or heteroaryl radical;
• m, m′, n, and n′, which may be identical or different, are integers ranging from 0 to 6, wherein m+n and m′+n′, which may be identical or different, are integers ranging from 1 to 10;
• An− is an anionic counterion;
• and
• Y is chosen from:
• i) a hydrogen atom;
• ii) an alkali metal;
• iii) an alkaline earth metal;
• iv) an ammonium group:
• N+RαRβRγRδ or a phosphonium group:
• P+RαRβRγRδ wherein Rα, Rβ, Rγ, and Rδ, which may be identical or different, are chosen from a hydrogen atom and a (C1-C4)alkyl group;
• and
• v) a thiol-function-protecting group;
• wherein when the compound of formula (I) or (II) comprises at least one other cationic part, it is associated with at least one anionic counterion allowing formula (I) or (II) to achieve electroneutrality.