N-p-Tosyl-L-arginine is widely used in biochemical research as a substrate for studying enzyme activity, particularly for enzymes like trypsin and other proteases. It helps in understanding enzyme kinetics and mechanisms due to its specific interaction with these enzymes. Additionally, it serves as a building block in peptide synthesis, where it is incorporated into larger peptide chains for various research purposes. Its role in inhibiting certain enzymatic reactions also makes it valuable in studying metabolic pathways and developing potential therapeutic agents.