High-affinity, non-nucleotide-derived competitive antagonists of platelet P2Y12 receptors.

Anthraquinone derivatives related to the moderately potent, nonselective P2Y(12) receptor antagonist reactive blue 2 (6) have been synthesized and optimized with respect to P2Y(12) receptor affinity. A radioligand binding assay utilizing human blood platelet membranes and the P2Y(12) receptor-selective antagonist radioligand [(3)H]2-propylthioadenosine-5'-adenylic acid (1,1-dichloro-1-phosphonomethyl-1-phosphonyl) anhydride ([(3)H]PSB-0413) was applied for compound testing. 1-Amino-2-sulfoanthraquinone derivatives bearing a (p-phenylamino)anilino substitution in the 4-position and an additional acidic function in the meta-position of the aniline ring showed high P2Y(12) receptor affinity.