Structural Modification of an Orally Active Thrombin Inhibitor, LB30057: Replacement of the D-Pocket-binding Naphthyl Moiety
摘要:
An amidrazonophenylalanine derivative LB30057 (2) was identified as a potent (K-i = 0.38 nM), selective, and orally active thrombin inhibitor. As a continuation of studies into benzamidrazone-based thrombin inhibitors, we have structurally modified compound 2 by replacing the naphthyl group with a variety of hydrophobic moieties. This study led to discovery of several compounds with significantly enhanced potency in thrombin inhibition without sacrificing selectivity against trypsin and oral absorption. The highest activity was obtained with compound 23 (K-i = 0.045 nM). (C) 1998 Elsevier Science Ltd. All rights reserved.
A series of p-aminomethylphenylalanine derivatives were investigated as novelthrombininhibitors. This study led to potentinhibitors of thrombin (Ki up to 3.3 nM) that are trypsin-selective, highly orally bioavailable in rats, and highly permeable across Caco-2 cells. The P1 benzylamine binding mode in the thrombinactivesite was identified by X-ray crystallographic analysis.