Used as a key intermediate in the synthesis of antiviral agents, particularly in the development of hepatitis C virus (HCV) protease inhibitors. Its spirocyclic structure and functional groups enable selective binding to enzyme active sites, enhancing drug potency. Commonly employed in medicinal chemistry for constructing complex heterocyclic systems that improve metabolic stability and bioavailability in drug candidates. Also utilized in research for designing new protease inhibitors due to its rigid framework and stereochemical properties.