Bismuth thiolate complexes

Thiolation is restricted by more effective nitrogen donors or steric limitations. The bis(aminothiolate) complexes are obtained from bismuth nitrate or chloride and the hydrogen chloride adduct of the thiol and essentially independent of stoichiometry. The nitrogen-bismuth interactions in these complexes [e.g., Bi(SCH2CH2NH2)2(N03)(H20) 54,... 

Inhibition of the dinuclear Ni(II) enzyme urease by Bi(III) thiolates may be important for its antibacterial activity. Helicobacter pylori relies on urease for the production of ammonia which allows survival under the highly acidic conditions of the gastric lumen and mucosa. Bismuth(III) mercaptoethanol complexes are ca. 103 more active inhibitors than mercaptoethanol alone (466). The thiol can bind directly to Ni(II) in the active site and also form a disulfide with a Cys residue in the active site cavity (467). 

While the mechanism of the interaction of these carboxylate complexes with the biological molecules that leads to their activity is not well understood, there is some evidence that the molecules can bind to N-donor and S-donor molecules in proteins. Bismuth(III) has been shown to bind most strongly to the thiolates in glutathione. There is some evidence that Bi(III) can replace metals such as Fe(III) in lactoferrin and transferrin or Zn(II) in metallothionein. ... 

The reaction of bismuth arenethiolates has been studied very little there is only one example of the reaction between thiolate 23 and 2 equiv. of Bi[M(CO)3(Ti-C5H5)]3 (M=Mo and W) to form a complex [Bi(SQF5) M(CO)3(iri -C5H5) 2] [95JCS(D)2129]. 

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