Used primarily in peptide synthesis as a protected amino acid building block. The Fmoc group provides temporary protection for the amine functionality, allowing selective reaction at the carboxylic acid site. This compound is especially useful in solid-phase peptide synthesis (SPPS), where its carboxylic acid group can be activated and coupled to amino groups of other amino acids. The aromatic fluorenyl group enables easy monitoring of reactions due to its UV activity. After chain assembly, the Fmoc group is removed under mild basic conditions, leaving other protecting groups intact, making it ideal for stepwise synthesis of complex peptides. Its structure also imparts solubility in common organic solvents, facilitating handling and purification.