Chloroalanine (3-chloroalanine) is an unnatural amino acid with the formula ClCH<sub>2</sub>CH(NH<sub>2</sub>)CO<sub>2</sub>H. It is a white, water-soluble solid. The compound is usually derived from chlorination of serine. The compound is used in the synthesis of other amino acids by replacement of the chloride. Protected forms of the related iodoalanine are also known.
The hydrolysis of 3-chloro-D-alanine is catalyzed by the enzyme 3-chloro-D-alanine dehydrochlorinase: