Used as an intermediate in the synthesis of pharmaceuticals, particularly in the development of sulfonamide-based drugs. Its reactive chlorosulfonyl group allows for easy attachment to amines, forming sulfonamide linkages common in antimicrobial and anti-inflammatory agents. Also employed in agrochemical synthesis for creating herbicides and plant growth regulators. Its ester functionality enables further modification, making it valuable in organic synthesis for building complex heterocyclic compounds.