Phthaloyl-DL-alanine is primarily used in the synthesis of peptides and other organic compounds. It serves as a protective group for amino acids during peptide bond formation, ensuring specific reactions occur without unwanted side interactions. This compound is particularly valuable in pharmaceutical research, where it aids in the development of new drugs by enabling precise control over molecular structures. Additionally, it is employed in biochemical studies to investigate enzyme mechanisms and protein interactions. Its stability and reactivity make it a useful intermediate in organic synthesis, contributing to advancements in medicinal chemistry and biotechnology.