Structural and functional analogue of the active site of polysulfide reductase from Wolinella succinogenes.

Synthesis of [PPh 4 ] 2 [Mo(SPh)2(S 2 C 2 (CN) 2 )2] (2) from [PPh 4 ] 2 [MoO-(S 2 C 2 (CN) 2 ) 2 ] (1) has been achieved to mimic the postulated {Mo-(S) 6 } core of polysulfide reductase with two thiolates and two bis(ene-dithiolate) ligands. Compound 2 reacts with polysulfide to yield H 2 S, modeling the function of polysulfide reductase. The facile conversion of 2 back to 1 in moist solvent suggests that the interconversion of the {Mo I V =O} and {MO I V -X} (X = O-Ser, S-Cys, Se-Cys) moieties might occur in the DMSO reductase class of enzymes under appropriate hydrophobic/hydrophilic conditions.