Used as a chromogenic substrate in enzymatic assays, particularly for studying protease activity. The compound is cleaved by specific enzymes such as elastase and chymotrypsin, releasing p-nitroaniline, which produces a yellow color detectable at 405 nm. This color change allows real-time monitoring of enzyme kinetics and inhibition, making it valuable in biochemical research and drug development. Commonly employed in assays to evaluate enzyme specificity, activity, and the effectiveness of protease inhibitors.