3-Chloro-D-alanine is a non-proteinogenic amino acid derivative characterized by a chloro substituent at the beta-carbon position of the D-alanine backbone. It serves as a chiral building block and a mechanism-based inhibitor. Its primary application is in pharmaceutical research and development. It acts as an irreversible inhibitor of several pyridoxal phosphate-dependent enzymes, such as D-amino acid transaminase and alanine racemase. This mechanism makes it a valuable tool for studying bacterial cell wall biosynthesis and for the development of potential antibacterial agents, as alanine racemase is a validated target for novel antibiotics. The compound is also utilized in organic synthesis as a source of chiral beta-chloro-alpha-amino acid motifs, which can be further functionalized. Due to its reactive nature and potential biological activity, appropriate safety precautions are required during handling.