摘要:
Unexpectedly, methyl and benzyl esters of 2-allyl-3-benzenepropanoic acid were found to be not substrates but potent competitive inhibitors for alpha-chymotrypsin. The inhibitory property of the structurally simple nonpeptidic compounds is ascribed to their high binding affinity to the enzyme at the S-2 rather than S-1 subsite pocket. These inhibitors exist in a flexible form in solution, but as they bind to the enzyme bulky contrained conformers present in a minute concentration play an important role, forming tighter enzyme-inhibitor complexes by binding to the large hydrophobic S-2 pocket. The contrained conformers are thought to be resulted from intramolecular CH/pi interactions between a vinylic proton and the aromatic pi-electron cloud in the inhibitor molecules. These compounds constitute novel examples of the induced-fit binding inhibitor of possibly simplest structure. (C) 1998 Elsevier Science Ltd. All rights reserved.