Patent ID: 8221721

Claim:
A compound represented by Formula I: or a salt thereof, wherein: X 1 and X 2 each independently are selected from the group consisting of C(CH 2 K 1 )(CH 2 K 2 ), O, S, and Se, wherein K 1 and K 2 each independently are selected from the group consisting of H and C 1 -C 20 alkyl; wherein K 1 and K 2 together can optionally form part of a cyclic ring; R 1 and R 2 each independently are selected from the group consisting of H, C 1-20 alkyl, alkylaryl, and —R 9 T 1 , wherein R 9 is independently selected from the group consisting of C 1 -C 20 alkyl, aryl, alkylaryl, and —(CH 2 —O—CH 2 ) y CH 2 , wherein y is an integer selected from 1 to 100, and T 1 is a linker moiety capable of forming a covalent bond with a biomolecule; X 3 is selected from the group consisting of H, halogen, -T 2 R 10 , -T 2 R 9 T 1 , and —R 9 T 1 , wherein T 2 is selected from the group consisting of S, O, and NR′, R 10 is selected from the group consisting of H, C 1-20 alkyl, aryl, arylalkyl; X 4 and X 5 each independently are selected from the group consisting of (CK 1 K 2 ) i ; NR′, —NR′R 9 T 1 , O, and S, wherein i is an integer selected from 1 to 7, and R′ is selected from the group consisting of H and alkyl; W 1 and W 2 each represent nonmetal atoms as part of an aryl moiety; n 1 and n 2 each independently are selected from 0 to 4; R 3 , R 4 , R 5 and R 6 each independently are selected from the group consisting of H, halogen, carboxylate, carboxylic acid, carboxylic ester, amine, amide, sulfonamide, hydroxyl, O-alkyl, S-alkyl, alkyl, sulfonic acid, sulfonate, a phosphoryl, SO 2 NR 7 -Q-CHR 8 —[(CH 2 ) m —Y—(CH 2 ) p —(O) k ] h (CH 2 ) d T 1 , and —R 9 T 1 , wherein R 7 independently is selected from the group consisting of C 1 -C 20 alkyl, aryl, alkylaryl, R 8 independently is selected from the group consisting of H, C 1 -C 20 alkyl, aryl, alkylaryl and arylalkyl; R 7 and R 8 , when taken in combination, optionally form a 4-, 5-, 6- or 7-member, optionally substituted, saturated or unsaturated ring, Q independently is selected from the group consisting of a bond, carbonyl, C 1 -C 6 alkyl, and C 1 -C 6 cycloalkyl, Y independently is selected from the group consisting of a bond, —SO 2 NR 1 —, —O—, —COO—, and —CONR′—, h is an integer selected from 0 to 70, k is 0 or 1, d is an integer from 0 to 12, m is an integer from 0 to 12, and p is an integer from 0 to 12.