Irreversible inhibitions of serine proteases by peptidyl allylic halide derivatives

Peptidyl 4-amino-5-phenyl-2-pentenyl bromide (7a, 9a, 10a) and chloride derivatives (7b, 9b, 10b) were found to be active-site directed irreversible inhibitors of α-chymotrypsin but did not show any irreversible inhibitory activity toward porcine pancreatic elastase.