Used as an intermediate in the synthesis of pharmaceuticals and agrochemicals, particularly in the production of sulfa drugs and herbicides. It serves as a building block in the development of sulfonamide-based compounds due to its reactive amine group and electron-withdrawing sulfonyl moiety. Its hydrochloride salt form enhances stability and solubility, making it suitable for use in aqueous reaction conditions. Also employed in dye manufacturing and in the preparation of specialty polymers requiring thermal and chemical resistance.