A novel series of tryptase inhibitors with a N-phenylphthalimide skeleton structurally derived from thalidomide (1) has been developed. Structure–activity relationship studies led to a potent and selective tryptase inhibitor, 2-(4-cyanophenyl) isoindole-1, 3-dione-5-yl 3-(2- aminopyridin-5-yl) propanoate (7), with the IC50 value of 78nM.
