Diacyl disulfides as the precursors for hydrogen persulfide (H2S2).

While hydrogen polysulfides (H2Sn, n ≥ 2) are believed to play regulatory roles in biology, their fundamental chemistry and reactivity are still poorly understood. Compounds that can produce H2Sn are useful tools. In this work we found that H2S2 could be effectively produced from diacyl disulfide precursors, triggered by certain nucleophiles, in both aqueous solutions and organic solvents. This method was used to explore redox reactions of H2S2, such as scavenging 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and reduction of tetrazines.