Used in peptide synthesis as a chiral building block for introducing phenylalanine derivatives with a vinyl-functionalized side chain. The vinyl group allows for post-synthetic modifications via cross-coupling reactions or polymerization, making it valuable in the development of functionalized biomaterials, bioconjugates, or stimuli-responsive peptides. The Fmoc protection enables compatibility with standard solid-phase peptide synthesis (SPPS), allowing stepwise assembly of custom sequences under mild basic conditions. Its stereochemistry ensures enantioselective incorporation, which is critical for maintaining biological activity in synthetic peptides.