Used as a key reagent in organic synthesis, particularly in the development of pharmaceuticals and agrochemicals. It acts as a sulfonylating agent, enabling the introduction of sulfonyl groups into various molecules, which can enhance their biological activity or stability. Commonly employed in the preparation of protease inhibitors and other bioactive compounds. Also utilized in chemical biology for labeling and modifying proteins due to its reactivity with nucleophilic amino acid residues like serine and lysine. Its ability to cross cell membranes makes it suitable for in situ applications in enzyme inhibition studies.