Used as a key intermediate in the synthesis of pharmaceutical compounds, particularly in the development of protease inhibitors and other bioactive molecules. Its spirocyclic structure and functional groups make it valuable for constructing complex heterocyclic systems in drug design. The tert-butoxycarbonyl (Boc) group allows for selective protection of amines during multi-step syntheses, enhancing reaction specificity. The carboxylic acid moiety enables further derivatization, such as amide bond formation, useful in creating peptide-like structures. Commonly employed in medicinal chemistry for optimizing pharmacokinetic properties and improving metabolic stability in candidate drugs.