Used primarily as a sulfonating agent in organic synthesis, it facilitates the introduction of the sulfonyl group into various organic compounds. This reagent is particularly valuable in peptide chemistry for protecting amino groups during the synthesis of peptides. It also plays a role in the preparation of sulfonamides, which are important in pharmaceutical applications due to their antibacterial properties. Additionally, it is utilized in the modification of polymers and in the synthesis of dyes, where sulfonation enhances solubility and binding properties. Its reactivity with alcohols and amines makes it a versatile tool in the development of complex organic molecules.