Used in solid-phase peptide synthesis as a protected amino acid building block. The Fmoc group provides temporary protection for the amine functionality, allowing selective coupling reactions on solid support. The alkene side chains enable post-assembly modifications via ring-closing metathesis or cross-coupling reactions, making it valuable for introducing conformational constraints or cyclic structures in peptide backbones. Commonly applied in the synthesis of peptidomimetics and bioactive peptide analogs with enhanced stability or receptor selectivity.