This compound is primarily used in peptide synthesis as a protected form of lysine. The Z (benzyloxycarbonyl) group protects the amino group, while the OtBu (tert-butyl ester) group protects the carboxyl group, allowing selective reactions to occur at other sites of the molecule. It is particularly valuable in solid-phase peptide synthesis (SPPS) where controlled deprotection and coupling steps are essential. The HCl form ensures stability and solubility in various solvents, facilitating its use in complex peptide chain assembly. Its application is crucial in producing peptides for pharmaceutical research, drug development, and biochemical studies.