Widely used in solid-phase peptide synthesis, this compound serves as a protected amino acid building block, particularly for incorporating phenylalanine derivatives with acid-sensitive side-chain protection. The Fmoc group allows for mild base deprotection, while the tert-butyl group on the aromatic ring shields the para-position from unwanted reactions during chain elongation. It is especially valuable in synthesizing complex peptides and proteins where orthogonal protection strategies are required. Its stability under various coupling conditions makes it compatible with automated peptide synthesizers, enhancing efficiency and yield in pharmaceutical and biochemical research.