Used as a chiral building block in the synthesis of pharmaceuticals, particularly in the development of protease inhibitors and other bioactive molecules. Its protected amino and carboxyl functional groups allow for selective reactions in peptide coupling and asymmetric synthesis. Commonly employed in the preparation of enzyme inhibitors where stereochemistry is critical for biological activity. Also utilized in the construction of complex molecules requiring enantiomerically pure intermediates, especially in the research and development of central nervous system agents and antiviral drugs.