Used as a chiral building block in the synthesis of pharmaceuticals, particularly in the development of protease inhibitors and other bioactive molecules. Its protected amine group and carboxylic acid functionality allow for selective peptide coupling, making it valuable in solid-phase and solution-phase peptide synthesis. The (S)-configuration and aromatic side chain enhance stereoselectivity and binding affinity in drug candidates, especially those targeting enzymes with hydrophobic active sites. Commonly employed in the preparation of intermediates for CNS agents and metabolic disorder treatments.