Used as a chiral building block in the synthesis of peptide-based pharmaceuticals. Its allyl functional group allows for selective modifications through cross-metathesis reactions, enabling the introduction of complex side chains. The Cbz (benzyloxycarbonyl) protecting group facilitates controlled deprotection during solid-phase or solution-phase peptide synthesis. Commonly employed in the preparation of enzyme inhibitors and bioactive peptides where stereochemistry is critical for activity. Also serves as an intermediate in the production of protease inhibitors and other therapeutic agents targeting viral or metabolic diseases.