Used as a chiral intermediate in the synthesis of pharmaceutical compounds, particularly in the development of active pharmaceutical ingredients (APIs) requiring high enantiomeric purity. Its protected alcohol and amine functionalities make it suitable for sequential coupling reactions in multi-step organic syntheses. Commonly employed in the preparation of protease inhibitors and other bioactive molecules where stereochemistry plays a critical role in biological activity. The tosylate group acts as a leaving group, enabling nucleophilic substitution to introduce various side chains, while the benzyl carbamate (Cbz) group protects the nitrogen and can be removed under mild conditions without affecting other functional groups. Widely applied in medicinal chemistry for constructing complex nitrogen-containing heterocycles.