Used as a proteasome inhibitor in biochemical research, particularly in studies related to protein degradation pathways. It serves as a synthetic substrate for testing proteolytic enzyme activity, especially in assays involving chymotrypsin-like or multicatalytic protease systems. Due to its peptide-based structure with specific stereochemistry, it enables selective interaction with active sites of target enzymes, making it valuable in drug development for cancer and neurodegenerative diseases. Commonly employed in in vitro assays to evaluate inhibitor efficacy and enzyme kinetics.