Used as a key reagent in organic synthesis, particularly in the preparation of sulfonamides and other sulfur-containing heterocycles. Its unique imino-thianone structure allows it to act as a sulfonating agent, transferring the -SO₂ group to nucleophiles under mild conditions. Commonly employed in pharmaceutical manufacturing for modifying bioactive molecules, enhancing metabolic stability. Also utilized in the development of functional materials, including polymers with improved thermal and oxidative resistance. Shows promise in agrochemical synthesis due to its ability to introduce sulfone moieties that increase compound efficacy.