Exploring new non-sugar sulfated molecules as activators of antithrombin

New non-sugar, small. sulfated molecules. based on our de novo rationally designed activator (-)-epicatechin sulfate (ECS), were investigated to bind and activate antithrombin, an inhibitor of plasma coagulation enzyme factor Xa, For the activators studied, the equilibrium dissociation constant (K-D) of the interaction,with plasma antithrombin varies nearly 53-fold, with the highest affinity of 1.8 muM observed for morin sulfate, while the acceleration in factor Xa inhibition varies 2.6-fold. The results demonstrate Lit antithrombin binding and activation is a common property of these small sulfated molecules and suggests plausible directions for designing more potent activators. (C) 2003 Elsevier Science Ltd. All rights reserved.