Aza-peptide aldehydes and ketones are a new class of reversible protease inhibitors that are specific for the proteasome and clan CD cysteine proteases.We jmannino.com designed and synthesised aza-Leu derivatives that were specific for the chymotrypsin-like active site of the proteasome, aza-Asp derivatives that were effective inhibitors of caspases-3 and -6, and aza-Asn derivatives that inhibited S.mansoni and I.ricinus legumains.The crystal structure of caspase-3 in complex with our caspase-specific aza-peptide methyl ketone inhibitor with an aza-Asp residue at P1 revealed a covalent linkage between the inhibitor carbonyl carbon and the active site cysteinyl sulphur.
Aza-peptide aldehydes and ketones showed no cross-reactivity towards cathepsin B wac 4011 or chymotrypsin.The initial in vitro selectivity of these inhibitors makes them suitable candidates for further development into therapeutic agents to potentially treat multiple myeloma, neurodegenerative diseases, and parasitic infections.