Used in peptide synthesis, particularly in solid-phase peptide synthesis (SPPS), as a protected amino acid derivative. The Fmoc group provides protection for the amino group during the synthesis process, while the O-t-butyl group protects the hydroxyl group of the tyrosine side chain. This allows for selective deprotection and coupling steps, enabling the construction of complex peptide sequences. It is especially valuable in the synthesis of peptides containing beta-homotyrosine, a non-natural amino acid, which can be incorporated into peptides to study structure-activity relationships or to enhance peptide stability and bioavailability. This compound is also utilized in the development of peptide-based drugs, biomaterials, and research tools for studying protein interactions and functions.