Used primarily as a key intermediate in the synthesis of biologically active compounds, especially in pharmaceuticals and agrochemicals. Its dual functionality, featuring both sulfonyl chloride and methylsulfonyl groups, allows for sequential derivatization, making it valuable in constructing sulfonamide-based molecules. Commonly employed in the development of protease inhibitors and kinase inhibitors due to its ability to enhance binding affinity and metabolic stability. Also utilized in the preparation of fluorescent probes and functional polymers where sulfonyl groups contribute to electron-withdrawing properties and thermal stability.