Patent ID: 8344177

Claim:
A compound represented by the following formula: wherein X is O or S; A is NH, O, S or CR 9 R 10 ; D is selected from the group consisting of OPO 3 H 2 , PO 3 H 2 , OSO 3 H, SO 3 H, COOH and the conjugate bases thereof; R 1 and R 2 are independently selected from the group consisting of H, F, Cl, Br, I, branched, unbranched or cyclic C 1 -C 10 hydrocarbyl groups, OR 9 , OCOR 9 , COOR 9 , CH 2 OR 9 , CHO, COR 9 , NR 9 R 10 and SR 9 ; or R 1 and R 2 are joined to form a cyclic structure comprising a branched, unbranched or cyclic C 1 -C 10 hydrocarbyl group wherein said hydrocarbyl group is optionally interrupted by up to 2 heteroatoms and optionally substituted by up to 3 groups independently selected from the group consisting of F, Cl, Br, I, OR 9 , OCOR 9 , COOR 9 , CHO, COR 9 , CH 2 OR 9 , NR 9 R 10 , CH 2 NR 9 R 10 , SR 9 , ═O, ═S and ═NH; R 3 -R 8 are independently selected from the group consisting of H, F, Cl, Br, I, branched, unbranched or cyclic C 1 -C 10 hydrocarbyl groups, OR 9 , OCOR 9 , COOR 9 , CHO, COR 9 , CH 2 OR 9 , NR 9 R 10 , CH 2 NR 9 R 10 and SR 9 ; or the pairs of substituents R 3 and R 4 together, R 5 and R 6 together, or R 7 and R 8 together are optionally independently selected from the group consisting of ═O, ═S and ═NH; B comprises a branched, unbranched or cyclic hydrocarbyl group of up to 30 carbon atoms optionally interrupted by up to 10 heteroatoms or a peptidyl chain of up to 20 amino acid residues, wherein B is optionally substituted with 1-5 groups selected from the group consisting of F, Cl, Br, I, ═O, OR 9 , OCOR 9 , COOR 9 , CN, NR 9 , NR 9 R 10 , ═S, and SR 9 , provided that B comprises at least 3 atoms in a chain between group D and the group A; Y is a functional group other than H, wherein Y is capable of bonding to a therapeutic or diagnostic agent molecule; and R 9 and R 10 are independently selected from the group consisting of H, branched, unbranched and cyclic C 1 -C 10 hydrocarbyl groups, and the salts thereof.