Boc-D-Cit-OH is widely used in peptide synthesis as a protecting group for the amino acid D-citrulline. Its primary application lies in the preparation of complex peptides and proteins, where it helps in preventing unwanted side reactions during the coupling process. This compound is particularly valuable in the synthesis of modified peptides for research in biochemistry and medicinal chemistry, enabling the study of protein interactions and enzyme mechanisms. Additionally, it plays a role in the development of peptide-based pharmaceuticals, where precise control over amino acid incorporation is critical. Its stability under various reaction conditions makes it a reliable choice for solid-phase peptide synthesis, facilitating the production of high-purity peptides for therapeutic and diagnostic purposes.