Used in peptide synthesis as a protected amino acid derivative, particularly in the preparation of complex peptides where selective deprotection and high purity are required. The xanthyl group provides orthogonal protection for the side chain amide, minimizing unwanted side reactions during coupling steps. Fmoc-Ngamma-xanthyl-D-asparagine is especially valuable in solid-phase peptide synthesis (SPPS), allowing for the incorporation of D-asparagine residues with enhanced stability and reduced racemization. Its use supports the synthesis of structurally defined peptides for research in medicinal chemistry and drug development.