Mechanism-based thrombin inhibitors: Design, synthesis, and molecular docking of a new selective 2-oxo-2H-1-benzopyran derivative

New 2-oxo-2H-1-benzopyran derivatives were prepared to optimize 2a,b, initially developed as mechanism-based α-chymotrypsin (α-CT) inhibitors, into potent and selective thrombin (THR) inhibitors. From this study, 22, characterized by a 2-(N-ethyl-2′-oxoacetamide)-5′- chlorophenyl ester side chain, was shown to be a good THR inhibitor (k _i/K _I = 3455 M ^-1·s ^-1), displaying an excellent selectivity profile against other serine proteases such as factor Xa, trypsin, and α-CT. Docking analysis of this compound into the different protein structures revealed the molecular basis responsible for its potency and selectivity.