Used as a key chiral intermediate in the synthesis of pharmaceutical agents, particularly in the development of protease inhibitors and antiviral drugs. Its cyclopentyl and amino ester functionalities make it valuable for constructing biologically active molecules with high stereoselectivity. Commonly employed in the preparation of hepatitis C virus (HCV) NS3/4A protease inhibitors due to its ability to mimic natural amino acid substrates. Also utilized in medicinal chemistry for structure-activity relationship (SAR) studies to optimize drug potency and metabolic stability.