Used as a chiral intermediate in the synthesis of pharmaceuticals, particularly in the production of protease inhibitors and other biologically active molecules. Its protected amine and ester functional groups allow for selective reactions in multi-step organic syntheses. Commonly employed in the development of peptide mimetics due to the presence of the 4-nitrophenyl group, which can act as a spectroscopic handle or be further modified. Suitable for asymmetric synthesis where stereochemical control is critical.