Unprecedented oxidation of a biologically active aroylhydrazone chelator catalysed by iron(III): serendipitous identification of diacylhydrazine ligands with high iron chelation efficacy

  title={Unprecedented oxidation of a biologically active aroylhydrazone chelator catalysed by iron(III): serendipitous identification of diacylhydrazine ligands with high iron chelation efficacy},
  author={Paul V. Bernhardt and Piao Chin and Des R. Richardson},
  journal={JBIC Journal of Biological Inorganic Chemistry},
Abstract. Ligands of the 2-pyridylcarbaldehyde isonicotinoylhydrazone class show high iron (Fe) sequestering efficacy and have potential as agents for the treatment of Fe overload disease. We have investigated the mechanisms responsible for their high activity. X-ray crystallography studies show that the tridentate chelate 2-pyridylcarbaldehyde isonicotinoylhydrazone undergoes an unexpected oxidation to isonicotinoyl(picolinoyl)hydrazine when complexed with FeIII. In contrast, in the absence of… 

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