N-Acetyl-S-benzyl-L-cysteine is primarily used in biochemical research as a protective agent for thiol groups in peptides and proteins. It helps prevent unwanted oxidation during synthesis or modification processes, ensuring the integrity of the thiol-containing compounds. Additionally, it serves as a precursor in the preparation of various cysteine derivatives, which are valuable in studying enzyme mechanisms and protein interactions. Its application extends to the development of pharmaceuticals, particularly in designing prodrugs or compounds that target specific biological pathways involving cysteine residues.