Used as a chiral building block in the synthesis of peptide-based pharmaceuticals, particularly in the preparation of enzyme inhibitors and bioactive peptides. Its protected amine and carboxylic acid functionalities make it suitable for solid-phase and solution-phase peptide coupling. The (S)-configuration ensures stereochemical control during synthesis, which is critical for achieving desired biological activity in final drug compounds. Commonly employed in the development of antiviral and anticancer agents where precise stereochemistry and functional group compatibility are required.