Used in peptide synthesis as a protected amino acid derivative, particularly in the preparation of complex peptides and proteins. The Fmoc group provides orthogonal protection for the amine, allowing stepwise assembly under mild basic conditions. The tert-butyl ureido moiety acts as a protecting group for side-chain functionality, offering stability during coupling steps and easy deprotection under acidic conditions. Commonly employed in solid-phase peptide synthesis (SPPS) for developing pharmaceuticals, biochemical probes, and enzyme inhibitors. Its structure supports high solubility in common organic solvents and facilitates purification due to distinct crystallinity.