Used as a bifunctional alkylating agent in organic synthesis, particularly in the preparation of cyclic compounds and macrocycles through intramolecular or intermolecular cyclization reactions. Its terminal mesyloxy groups are good leaving groups, making it effective for nucleophilic substitution reactions. Commonly employed in the synthesis of crown ethers, cryptands, and other host molecules in supramolecular chemistry. Also utilized as a linker or spacer in polymer chemistry and in the modification of biomolecules where controlled spacing between functional groups is required.