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 multiple functional groups allow for selective modifications, making it valuable in medicinal chemistry for constructing complex heterocyclic systems. The presence of orthogonal protecting groups (benzyloxycarbonyl and tert-butoxycarbonyl) enables stepwise deprotection and coupling reactions, facilitating its use in solid-phase and solution-phase peptide-like synthesis. It is also employed in the preparation of enzyme inhibitors where precise stereochemistry and ring constraints enhance binding affinity and metabolic stability.