A compound having a structure of formula: wherein R 2 is optionally substituted C 1 -C 10 alkyl; each R 3 is independently halogen, CN, CF 3, SR 2, SOR 2, SO 2 R 2, OR 2, CO 2 H, CO 2 R 2, N(R 2) 2, NHR 2, NO 2, or R 2; Z is N; R 4 and R 5 are independently hydrogen, halogen, CN, CF 3, SR 2, SOR 2, SO 2 R 2, OR 2, CO 2 H, CO 2 R 2, N(R 2) 2, NHR 2, NO 2, or R 2; R 9 and R 10 are independently hydrogen, optionally substituted linear or branched C 1 -C 10 alkyl, optionally substituted linear or branched C 2 -C 10 alkenyl, optionally substituted linear or branched C 2 -C 10 alkynyl, optionally substituted C 4 -C 8 cyclyl, optionally substituted C 3 -C 8 heterocyclyl, provided that at least one of R 9 and R 10 is not hydrogen, or R 9 and R 10 together with the carbon they are attached to form an optionally substituted 3-8 membered cyclyl or heterocyclyl; L 2 is a bond, optionally substituted linear or branched C 1 -C 10 alkylene, optionally substituted linear or branched C 2 -C 10 alkenylene, or optionally substituted linear or branched C 2 -C 10 alkynylene, wherein the backbone of C 1 -C 10 alkylene, C 2 -C 10 alkenylene, or C 2 -C 10 alkynylene optionally comprises one or more heteroatoms; T is H, a linear or branched, substituted or unsubstituted C 1 -C 10 alkyl, linear or branched, substituted or unsubstituted C 2 -C 10 alkenyl, linear or branched, substituted or unsubstituted C 2 -C 10 alkynyl, optionally substituted cyclyl, optionally substituted aryl, or PEG, wherein the backbone of C 1 -C 10 alkyl, C 2 -C 10 alkenyl, C 2 -C 10 alkynyl optionally comprises one or more heteroatoms; and n is an integer of 0-5, or a salt, solvate, or ester thereof. R 2 is optionally substituted C 1 -C 10 alkyl; each R 3 is independently halogen, CN, CF 3, SR 2, SOR 2, SO 2 R 2, OR 2, CO 2 H, CO 2 R 2, N(R 2) 2, NHR 2, NO 2, or R 2; Z is N; R 4 and R 5 are independently hydrogen, halogen, CN, CF 3, SR 2, SOR 2, SO 2 R 2, OR 2, CO 2 H, CO 2 R 2, N(R 2) 2, NHR 2, NO 2, or R 2; R 9 and R 10 are independently hydrogen, optionally substituted linear or branched C 1 -C 10 alkyl, optionally substituted linear or branched C 2 -C 10 alkenyl, optionally substituted linear or branched C 2 -C 10 alkynyl, optionally substituted C 4 -C 8 cyclyl, optionally substituted C 3 -C 8 heterocyclyl, provided that at least one of R 9 and R 10 is not hydrogen, or R 9 and R 10 together with the carbon they are attached to form an optionally substituted 3-8 membered cyclyl or heterocyclyl; L 2 is a bond, optionally substituted linear or branched C 1 -C 10 alkylene, optionally substituted linear or branched C 2 -C 10 alkenylene, or optionally substituted linear or branched C 2 -C 10 alkynylene, wherein the backbone of C 1 -C 10 alkylene, C 2 -C 10 alkenylene, or C 2 -C 10 alkynylene optionally comprises one or more heteroatoms; T is H, a linear or branched, substituted or unsubstituted C 1 -C 10 alkyl, linear or branched, substituted or unsubstituted C 2 -C 10 alkenyl, linear or branched, substituted or unsubstituted C 2 -C 10 alkynyl, optionally substituted cyclyl, optionally substituted aryl, or PEG, wherein the backbone of C 1 -C 10 alkyl, C 2 -C 10 alkenyl, C 2 -C 10 alkynyl optionally comprises one or more heteroatoms; and n is an integer of 0-5,