Z-4-chloro-DL-phenylalanine is primarily utilized in biochemical research as a tool to study enzyme inhibition, particularly in the context of phenylalanine metabolism. It is often employed to investigate the activity of enzymes like phenylalanine hydroxylase, which plays a critical role in the conversion of phenylalanine to tyrosine. By acting as a competitive inhibitor, this compound helps researchers understand enzyme kinetics and the biochemical pathways associated with amino acid metabolism. Additionally, it is used in studies related to metabolic disorders such as phenylketonuria (PKU), providing insights into potential therapeutic strategies. Its application extends to the development of assays and experimental models to explore the effects of enzyme dysfunction in biological systems.