Used in solid-phase peptide synthesis as a protected amino acid building block, particularly for incorporating aminoadipic acid derivatives into peptide chains. The Fmoc group allows for mild base deprotection, while the tert-butyl ester protects the side chain carboxylic acid, enabling selective deprotection under acidic conditions. Commonly applied in the synthesis of complex peptides and modified proteins for research in biochemistry and drug development. Its orthogonal protection scheme makes it suitable for use in automated peptide synthesizers.