Used primarily as a key intermediate in the synthesis of sulfa drugs and agrochemicals. Its electrophilic sulfonyl chloride group readily reacts with amines to form sulfonamides, which are important structural motifs in pharmaceuticals. Particularly valuable in the preparation of fluorinated bioactive compounds, where the fluorine atoms enhance metabolic stability and membrane permeability. Also employed in the development of herbicides and fungicides due to the combined effect of fluorine and sulfonyl functionalities, improving lipophilicity and target binding. Commonly used in medicinal chemistry for building blocks in drug discovery programs targeting enzyme inhibitors.