This compound is widely used in peptide synthesis, particularly in solid-phase peptide synthesis (SPPS) methods. It serves as a protected amino acid derivative, where the Fmoc (fluorenylmethyloxycarbonyl) group protects the amino group, and the Dde (1-(4,4-dimethyl-2,6-dioxocyclohexylidene)ethyl) group protects the side chain amine of lysine. This dual protection allows for selective deprotection, enabling the controlled synthesis of complex peptides. It is especially valuable in the synthesis of peptides that require orthogonal protection strategies, such as those involving multiple lysine residues or post-synthetic modifications. Its application is critical in producing peptides for pharmaceutical research, drug development, and biochemical studies.