This compound is a protected dipeptide derivative featuring L-leucine and L-threonine, connected via an ester linkage between the carboxyl group of L-leucine and the side-chain hydroxyl group of L-threonine. The amino group of L-leucine is protected by the fluorenylmethoxycarbonyl (Fmoc) group, serving as a temporary protecting group that can be selectively removed under basic conditions. The amino group of L-threonine is protected by the tert-butoxycarbonyl (Boc) group, which is orthogonal to Fmoc and removable under acidic conditions. This dual protection facilitates controlled deprotection and coupling reactions in solid-phase peptide synthesis (SPPS), enabling the precise assembly of complex peptide chains with potential branched or modified structures. It is widely used in biochemical research, pharmaceutical development, and biotechnology for synthesizing high-purity peptides and proteins.