Used in the synthesis of antiviral agents, particularly as an intermediate in the production of hepatitis C virus (HCV) protease inhibitors. Its stereochemistry and functional groups make it valuable for constructing complex peptide-like structures that target viral enzymes. Commonly employed in pharmaceutical research to develop orally active drugs with improved metabolic stability and bioavailability. Also utilized in structure-activity relationship (SAR) studies to optimize inhibitor potency and selectivity.