Used as a highly effective protein modification reagent in chemical biology and proteomics research. Its primary application lies in covalent labeling of proteins, particularly for identifying and characterizing active sites of enzymes. The sulfonyl fluoride group reacts selectively with nucleophilic amino acid residues such as lysine, tyrosine, and serine, making it valuable for irreversible inhibition and target engagement studies. Due to its stability in aqueous environments and good selectivity, it serves as a key component in the development of activity-based protein profiling (ABPP) probes. It is also employed in the synthesis of covalent inhibitors for drug discovery, enabling the study of protein function and validation of therapeutic targets.