Used as a key intermediate in the synthesis of proteasome inhibitors, particularly in the production of anticancer drugs like carfilzomib. Its chiral structure enables selective binding to proteasome subunits, enhancing drug efficacy. The trifluoroacetate salt form improves solubility and stability during peptide coupling reactions. Commonly employed in pharmaceutical research for developing targeted therapies against multiple myeloma and other hematologic malignancies.