N-Boc-3-Chloro-L-alanine methyl ester is a protected amino acid derivative. It features a tert-butoxycarbonyl (Boc) group protecting the amine functionality, a methyl ester protecting the carboxylic acid, and a chloro substituent on the beta-carbon of the alanine backbone. This specific structure makes it a chiral, functionalized building block. This compound is primarily used as a key intermediate in the synthesis of more complex molecules, particularly in pharmaceutical research. The presence of the reactive chloro group allows for further functionalization, such as nucleophilic substitution or cyclization reactions. It is employed in the preparation of peptide mimetics, protease inhibitors, and other bioactive compounds where the chloroalanine moiety is a critical structural element. As a specialty synthetic intermediate, it is not a commodity chemical and is typically utilized in laboratory-scale research and development for drug discovery programs. Proper handling precautions are advised due to its potential reactivity.