Gold complexes 2,3-dimercaptopropanol

Model reactions on [AuCl(PEt3)] with GSH show chloride displacement but no phosphine displacement [40], and intracellular GSH binding to auranofin was also observed by NMR studies on red cells [14]. The presence of the phosphine, necessary for oral administration, may also dictate some of the biochemical differences between auranofin and the injectable gold complexes. The breakdown of auranofin eventually produces Et PO, a reaction interestingly mimicked by 2,3-dimercaptopropanol (or British Anti-Lewisite) in its reactions with gold—phosphine complexes [14]. The phosphine oxide has recently been detected in human serum [41], supporting the theory that, upon cellular distribution, loss of phosphine results in behavior similar to that of non-phosphine containing complexes. 

These thiolate exchange reactions are thought to lead to incorporation of gold(I) to thiolate functions in proteins and enzymes, and thence to interfere with the inflammatory process. Thiols such as 2,3-dimercaptopropanol (BAL), iV-acetylcysteine and penicillamine have also been used in the treatment of gold toxicity. Protein-bound gold is mobilized by complexation to the added thiol and can then be excreted.250,273... 

Dithiols give several stable square planar gold(III) complexes. Some complexes of biochemical interest are those derived from 2,3-dimercaptopropanol (BAL),230 dimercaptosuc-cinic acid249 and penicillamine.542 These are thought to have structures similar to that of the toluenedithiolate derivative (72).543 They can be prepared by reaction of [AuCLJ- with the dithiol and base or by oxidation of gold in the presence of the dithiol. 

Similar unfavorable constants can be obtained for the other cases. A successful agent in complexing the Hg(II) is BAL (British anti-Lewisite), 2,3-dimercaptopropanol, with potent sulfur ligands for the mercury, and also for arsenic, antimony, bismuth, and gold. It is injected intramuscularly in 10% solution in peanut oil at a dose rate of 3 mg/kg of body weight every 4 hr for two days, and after that at decreasing frequency until recovery. 

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