Inhibitory potential of some chalcones on cathepsins B, H and L

Cathepsins, intracellular proteases, are known to be involved in a number of physiological processes such as degradation of extracellular proteins, prohormone processing, progressions of atherosclerosis etc. High levels of cathepsins have also been indicated in various pathological conditions like arthritis, cancer etc. One of the reasons for these elevated levels is attributed to a decrease in inhibitor concentration. Therefore, the work on the identification of small molecular weight compounds as inhibitors of cysteine proteases is of great therapeutic significance. In the present work, we report the synthesis of a small library of chalcones and a study of their role as inhibitors of cysteine proteases. After a preliminary screening of the compounds as inhibitors of cysteine proteases in general, studies were carried out to evaluate their inhibitory effects on cathepsin B, H and L. The most potent inhibitors among all the compounds were nitro substituted compounds for cathepsin B and cathepsin L and chloro substituted compounds for cathepsin H, respectively.