Redox Chemistry and [Au(CN)2-] in the Formation of Gold Metabolites

The role of hypochlorite ion, which can be generated by the enzyme myleoperoxidase, in the biochemistry of gold(I) anti-arthritic drugs was investigated. Sodium hypochlorite (OCl−) directly and rapidly oxidizes AuSTm, Au(CN)2-, AuSTg (gold thioglucose) and auranofin (Et3PAuSATg). The resulting gold(III) species were detected by an Ion Chromotography Ion-Pairing technique that was developed to distinguish gold(I) and gold(III). Formation of Au(III) was also demonstrated spectrophotometrically after the conversion to AuCl4−. The reactions of AuSTm, AuSTg, and auranofin are complex and gold(III) appears only after the initial oxidation of the thiolate (and phosphine) ligands