Used in peptide synthesis, particularly in solid-phase peptide synthesis (SPPS) as a building block. It helps introduce D-Phe(3,4-DiF) residues into peptides, which can enhance stability and biological activity. Commonly applied in the development of peptide-based drugs, research on enzyme inhibitors, and studies involving peptide-protein interactions. Its Fmoc group allows for easy deprotection during synthesis, making it a valuable tool in organic and medicinal chemistry.