Z-Leu-Leu-OH is primarily utilized in biochemical research as a substrate or inhibitor in studies involving proteases, particularly those that cleave peptide bonds. It is often employed to investigate enzyme kinetics and mechanisms, helping to elucidate the specificity and activity of proteolytic enzymes. Additionally, it serves as a building block in peptide synthesis, enabling the creation of more complex peptide structures for further study. In drug discovery, it can be used to develop and test potential protease inhibitors, which are relevant in treating diseases where protease activity is dysregulated, such as cancer or viral infections. Its role in mimicking natural peptide substrates makes it a valuable tool in understanding biological processes and designing therapeutic agents.