Widely used in peptide synthesis, this compound serves as a key intermediate for introducing protected amino acid building blocks. Its Fmoc group enables orthogonal protection strategies, allowing selective deprotection under mild basic conditions while maintaining stability during coupling steps. The carboxylic acid functionality readily activates for amide bond formation, making it valuable in solid-phase and solution-phase peptide assembly. It is especially useful in the preparation of complex peptides and peptidomimetics where controlled stepwise synthesis is required. Its methoxy carbonyl group can be further modified or removed depending on the synthetic pathway, offering flexibility in designing peptide sequences with specific side-chain protections.