Copper Bisthiosemicarbazone Complexes as Hypoxic Selective Agents

2 Copper Bisthiosemicarbazone Complexes as Hypoxic Selective Agents 

We found that for the hypoxic selective atsm and ptsm complexes the reduction process is reversible (Nernstian) and addition of small amounts of acid has little effect. By contrast [Cu(gts)] shows a very much less reversible reduction process which becomes completely irreversible on the addition of even traces of acid. This suggests strongly that the stability of the Cu state is crucial in determining the selectivity and that irreversibility is caused by protic attack on the anion. But the question of why backbone methylation should increase the stability of the Cu state has remained unanswered. 

The Chemistry and Applications of Complexes with Sulfur Ligands 

Takagi and R. Noyori, Science, 1998, 281, 1646 and references therein. 

Fujibayashi, K. Wada, H. Taniuchi, Y. Yonekura, J. Konishi and A. Yokoyama, Biol. Pharm. Bull., 1993,16,146. 

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