Sulfonyl fluorides (SFs) have recently emerged as a promising warhead for the targeted covalent modification of proteins in drug discovery and Post-polymerization modification(PPM) in polymer science. Sulfonyl fluoride buidlding blocks can be used as a connector for the assembly of -SO2- linked small molecules with proteins or nucleic acids. This newly-defined click chemistry approach through sulfates is a complimentary approach to using amides and phosphate groups as linkers.
Sulfur(VI) Fluoride Exchange (SuFEx): Another Good Reaction for Click Chemistry. 
A study of the reactivity of S(VI)–F containing warheads with nucleophilic amino-acid side chains under physiological conditions.