Melanin Binding Agents for Targeted Topical Delivery

A method for targeted delivery of a benefit agent to areas of human integument having melanin deposits, comprising topically applying to said integument a composition comprising the reaction product of a benefit agent and compound capable of binding to melanin having the structure of Formula (I):

• wherein, L is a divalent C4-32 hydrocarbon moiety, optionally substituted with heteroatoms selected from Si, O, S, N, and halogen, and optionally substituted with one or more groups R;
• and is a functional group capable of forming a bond with said benefit agent;
• for conjugating said compound to a benefit agent, and
• R1-R5 are independently selected, at each occurrence, from a group R;
• wherein R is selected from hydrogen, —F;
• —Cl;
• —Br;
• —I;
• —OH, —OR*;
• —NH2;
• —NHR*;
• —N(R*)2;
• —N(R*)3+;
• —N(R*)—OH;
• —N(→O)(R*)2;
• —O—N(R*)2;
• —N(R*)—O—R*;
• —N(R*)—N(R*)2;
• —C═N—R*;
• —N═C(R*)2;
• —C═N—N(R*)2;
• —C(═NR*)—N(R*)2;
• —SH;
• —SR*;
• —C≡N, —NC;
• —(C═O)—R*;
• —CHO;
• —CO2H;
• —CO2−;
• —CO2R*;
• —C(═O)Cl, —(C═O)—S—R*;
• —O—(C═O)—H;
• —O—(C═O)—R*;
• —S—(C═O)—R*;
• —(C═O)—NH2;
• —(C═O)—N(R*)2;
• —(C═O)—NHNH2;
• —O—(C═O)—NHNH2;
• —(C═S)—NH2;
• —(C═S)—N(R*)2;
• —N(R*)—CHO;
• —N(R*)—(C═O)—R*;
• —(C═NR)—O—R*;
• —O—(C═NR*)—R*, —SCN;
• —NCS;
• —NSO;
• —SSR*;
• —N(R*)—C(═O)—N(R*)2;
• —N(R*)—C(═S)—N(R*)2;
• —SO2—R*;
• —O—S(═O)2—R*;
• —S(═O)2—OR*;
• —N(R*)—SO2—R*;
• —SO2—N(R*)2;
• —O—SO3−;
• —O—S(═O)2—OR*;
• —O—S(═O)—OR*;
• —O—S(═O)—R*;
• —S(═O)—OR*;
• —S(═O)—R*;
• —NO;
• —NO2;
• —NO3;
• —O—NO;
• —O—NO2;
• —N3;
• —N2—R*;
• —N(C2H4);
• —Si(R*)3;
• —CF3;
• —O—CF3;
• —PR*2;
• —O—P(═O)(OR*)2;
• —P(═O)(OR*)2;
• —CH3, —CR*═CR*2, —C≡CH, —Si(OR*)3, —Si(R*)2H, C1-C12 perfluoroalkyl;
• an aliphatic C1-C12 hydrocarbon radical;
• a C1-C12 aromatic hydrocarbon radical;
• or a C1-C12 heteroaryl radical;
• R* is independently at each occurrence hydrogen or a straight chained, branched, or cyclic C1-C20 hydrocarbon radical, which may be saturated, partially saturated, or aromatic, each of which may be optionally substituted with 1-6 heteroatoms selected from nitrogen, oxygen, sulfur, or halogen, and wherein any two adjacent R* groups may together form a 3-8 membered aromatic, partially unsaturated, or saturated ring.
• and topically acceptable salts thereof.

The reaction product of an inorganic oxide particle and a compound of Formula (I):

• where L has the form —(CH3)z—, where “z” is an integer from 6-18;
• Ω is a trialkoxysilane of the form —Si(OR*)3, where R* is independently selected at each occurence from C1-6 hydrocarbons;
• and
• R1, R2, R4, and R5 are hydrogen, R3 is hydrogen, —CH3, —OCH3, —OH, —SH, or —NH2.