Taming sulfur dioxide: a breakthrough for its wide utilization in chemistry and biology

Although sulfur dioxide (SO2) has been used as a reagent for organic chemistry for more than one. hundred years, being endowed with quite a distinct and varied reactivity profile, which allows the synthesis of a large range of compounds, its notorious toxicity as well as its gaseous state have impeded its frequent utilization by chemists. We summarize recent studies in this emerging area aimed at stimulating its utilization in organic (including organometallic) chemistry thanks to the development of innocuous, bench-stable reliable SO2 donors. Proof-of-concept experiments have also been recently performed in biology with the design of organic SO2 donors having controlled release profiles under physiological conditions, either active against mycobacteria or used for clarifying the role of endogenously produced SO2 in living cells.