Used primarily as an intermediate in organic synthesis, especially in the preparation of pharmaceutical compounds. It plays a key role in the development of kinase inhibitors and other biologically active molecules due to its ability to form covalent bonds with target proteins. Commonly employed in medicinal chemistry for structure-activity relationship studies, particularly in cancer and inflammation research. Its reactive chloromethyl group allows for easy alkylation or conjugation with other functional groups, making it valuable in the design of drug candidates and biochemical probes.