abstract |
A class of cysteine protease inhibitors which inactivate a cysteine protease by covalently bonding to the protease and releasing a heterocyclic leaving group is presented. The cysteine protease inhibitors of the present invention comprise a first portion which targets a desired cysteine protease and positions the inhibitor near the thiolate anion portion of the active site of the protease, and a second portion which covalently bonds to the cysteine protease and irreversibly deactivates that protease by providing a carbonyl or carbonyl-equivalent which is attacked by the thiolate anion of the active site of the cysteine protease to sequentially cleave a heterocyclic leaving group. The heterocyclic leaving group of the protease inhibitor is of the formula: -O-Het, where Het is a heterocycle having 4-7 atoms in the ring, with at least one of the heterocycle atoms being N, O or S. |