Used primarily as a highly selective covalent inhibitor in biochemical research, particularly in activity-based protein profiling (ABPP). It reacts with active site residues of specific enzymes, enabling the identification and characterization of functional proteins in complex biological systems. Its sulfonyl fluoride group forms stable bonds with nucleophilic amino acids like serine and lysine, making it valuable for studying enzyme activity in live cells and tissue samples. Due to its ability to cross cell membranes, it is also employed in target discovery and validation for drug development.