Fmoc-(R)-3-amino-5-hexenoic acid is primarily used in peptide synthesis, particularly in solid-phase peptide synthesis (SPPS). It serves as a building block for introducing specific structural motifs into peptides. The Fmoc (fluorenylmethyloxycarbonyl) group acts as a protective group for the amine functionality, allowing controlled deprotection during synthesis. The compound’s hexenoic acid moiety provides a reactive site for further functionalization or conjugation, making it valuable in designing peptide-based drugs, biomaterials, or probes. Its chiral center ensures the incorporation of stereochemistry into the peptide chain, which is crucial for biological activity in many therapeutic peptides. Additionally, the double bond in the hexenoic acid side chain can be utilized in click chemistry or cross-linking reactions, expanding its utility in bioconjugation and material science applications.