Method of quenching singlet and triplet excited states of pigments, such as porphyrin compounds, particularly protoporphyrin IX, with conjugated fused tricyclic compounds have electron withdrawing groups, to reduce generation of reactive oxygen species, particularly singlet oxygen

A method of suppressing the generation of a reactive oxygen species selected from the group consisting of singlet oxygen, superoxide anion, peroxide, hydroxyl radical, hydroxyl ion, and mixtures thereof, by an excited pigment when mammalian endogenous pigment is exposed to light, thereby exciting the pigment to an excited state, by quenching the excited state of the pigment compound with a conjugated fused tricyclic compound having electron withdrawing groups of Formula (II) or a salt thereof:

• wherein:
• A is selected from the group consisting of O, S, C═O, C═S,
• B1, B2, D1, and D2 are each independently selected from the group consisting of F, Cl, Br, I, CF3, CCl3, NR33+, NO2, CN, C(═O)R4, C(═O)OR1, SO2R5, aryl, and —C═CHR6;
• each m independently is 0, 1, 2, 3, or 4;
• n is 0 or 1;
• each R1 is independently selected from the group consisting of H, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, and aryl;
• R2 is selected from the group consisting of H, alkyl, cycloalkyl, alkenyl, alkynyl, and aryl;
• each R3 is independently selected from the group consisting of H and C1-C6 alkyl;
• each R4 is independently selected from the group consisting of H, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, and aryl;
• each R5 is independently selected from the group consisting of H, O−, OH, NH2, and Cl;
• and,
• each R6 is independently selected from the group consisting of alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, and aryl,
• wherein if B1═CN, and B2═C(═O)OR1, then R1≠alkyl or cycloalkyl
• wherein if n=0, B1═CN, then B2≠CN, and
• wherein if n=0, B1═C(═O)OR1, and B2═C(═O)OR1, then R1≠alkyl or cycloalkyl.

A method of protecting skin from oxidative stress caused by the photogeneration of a reactive oxygen species from the group consisting of singlet oxygen, superoxide anion, peroxide, hydroxyl radical, hydroxyl ion, and mixtures thereof, comprising coating the skin with a pigment excited state quencher capable of accepting or donating an electron from or to a pigment compound in the excited state and returning the excited pigment compound to its ground state, said pigment quencher comprising a conjugated fused tricyclic compound having electron withdrawing groups of Formula (II) or a salt thereof:

• wherein:
• A is selected from the group consisting of O, S, C═O, C═S,
• B1, B2, D1, and D2 are each independently selected from the group consisting of F, Cl, Br, I, CF3;
• CCl3, NR33+, NO2, CN, C(═O)R4, C(═O)OR1, SO2R5, aryl, and —C═CHR6;
• each m independently is 0, 1, 2, 3, or 4;
• n is 0 or 1;
• each R1 is independently selected from the group consisting of H, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, and aryl;
• R2 is selected from the group consisting of H, alkyl, cycloalkyl, alkenyl, alkynyl, and aryl;
• each R3 is independently selected from the group consisting of H and C1-C6 alkyl;
• each R4 is independently selected from the group consisting of H, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, and aryl;
• each R5 is independently selected from the group consisting of H, O−, OH, NH2, and Cl;
• and,
• each R6 is independently selected from the group consisting of alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, and aryl,
• wherein if B1═CN, and B2═C(═O)OR1, then R1≠alkyl or cycloalkyl
• wherein if n=0, CN, then B2≠CN, and
• wherein if n=0, B1═C(═O)OR1, and B2═C(═O)OR1, then R1≠alkyl or cycloalkyl.

A method of protecting healthy cells adjacent to cancerous or pre-cancerous cells undergoing photodynamic therapy comprising applying a composition comprising a pigment excited state quencher compound to said adjacent cells to reduce the generation of reactive oxygen species from said healthy cells while the photodynamic therapy generates free radical oxygen from said cancerous or pre-cancerous cells, with a conjugated fused tricyclic compound having electron withdrawing groups of Formula (II) or a salt thereof:

• wherein:
• A is selected from the group consisting of O, S, C═O, C═S,
• B1, B2, D1, and D2 are each independently selected from the group consisting of F, Cl, Br, I, CF3, CCl3, NR33+, NO2, CN, C(═O)R4, C(═O)OR′, SO2R5, aryl, and —C═CHR6;
• each m independently is 0, 1, 2, 3, or 4;
• n is 0 or 1;
• each R1 is independently selected from the group consisting of H, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, and aryl;
• R2 is selected from the group consisting of H, alkyl, cycloalkyl, alkenyl, alkynyl, and aryl;
• each R3 is independently selected from the group consisting of H and C1-C6 alkyl;
• each R4 is independently selected from the group consisting of H, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, and aryl;
• each R5 is independently selected from the group consisting of H, O−, OH, NH2, and Cl;
• and,
• each R6 is independently selected from the group consisting of alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, and aryl,
• wherein if B1═CN, and B2═C(═O)OR1, then R1≠alkyl or cycloalkyl
• wherein if n=0, B1═CN, then B2≠CN, and
• wherein if n=0, B1═C(═O)OR1, and B2═C(═O)OR1, then R1≠alkyl or cycloalkyl.

A cosmetic or dermatological composition for coating a skin surface to protect the skin from getting damaging amounts of photogenerated reactive oxygen species when skin cell-contained or blood-contained pigments are exposed to sunlight, or other visible light comprising a cosmetically acceptable carrier, and a compound of Formula IIh, IIi, IIj, IIk, IIl, IIm, IIn or a combination thereof:

• and mixtures thereof,
• wherein:
• each R1 is independently selected from the group consisting of H, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, and aryl;
• and,
• R2 is selected from the group consisting of H, alkyl, cycloalkyl, alkenyl, alkynyl, and aryl.

A method of quenching excited state energy from a pigment that has been excited by absorption of light having a wavelength in the wavelength range of 290-800 nm, comprising reacting a pigment with a conjugated fused tricyclic compound having electron withdrawing groups of Formula (II-2) or a salt thereof:

• wherein:
• B1, B2, D1, and D2 are each independently selected from the group consisting of F, Cl, Br, I, CF3, CCl3, NR23+, NO2, CN, C(═O)R3, C(═O)OR1, SO2R4, aryl, and —C═CHR5;
• each m independently is 0, 1, 2, 3, or 4;
• each R′ is independently selected from the group consisting of H, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, and aryl;
• each R2 is independently selected from the group consisting of H and C1-C6 alkyl;
• each R3 is independently selected from the group consisting of H, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, and aryl;
• each R4 is independently selected from the group consisting of H, O−, OH, NH2, and Cl;
• and,
• each R5 is independently selected from the group consisting of alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, and aryl,
• wherein if B1 CN, and B2═C(═O)OR1, then R1≠alkyl or cycloalkyl,
• Wherein if B1═CN, then B2≠CN, and
• wherein if B1═C(═O)OR1, and B2═C(═O)OR1, then R1≠alkyl or cycloalkyl.