Probing the potential of platinum(II) complexes for the inhibition of thiol-dependent enzymatic activity

The synthesis and biological evaluation of platinum(II) amine complexes designed to act as inhibitors of the human cysteine protease cathepsin B, a thiol-dependent enzyme, is described. The complexes, composed of a cathepsin targeting ligand and a platinum(II) moiety with varying degrees of reactivity towards nucleophiles were characterized by physical-analytical methods and a proof of principle was illustrated in a model reaction. In biological tests for inhibitory activity against cathepsin B the presented compounds did not show significant inhibitory activity.