BOC-CYS-OH is widely used in peptide synthesis as a protecting group for cysteine residues. It helps prevent unwanted side reactions during the formation of peptide bonds, ensuring the correct sequence and structure of the peptide. This compound is particularly valuable in the production of complex peptides and proteins, where the precise arrangement of amino acids is critical. Additionally, it is employed in the development of pharmaceuticals, including drugs targeting cancer, autoimmune diseases, and infections, due to its role in stabilizing cysteine-containing peptides. Its application also extends to biochemical research, where it aids in studying protein folding, function, and interactions.