Nordesferriferrithiocin, NDFFTH2, is a derivative of the siderophore desferriferrithiocin, DFFTH2, in which the methyl group is substituted by a hydrogen atom. Both compounds show high oral activity as possible drugs for the treatment of iron overload. While DFFTH2 is significantly toxic, NDFFTH2 exhibits a lower toxicity and offers a much better therapeutic window than other orally active iron chelators. In this study, complexes of DFFTH2 and NDFFTH2 with various trivalent metals have been synthesized and characterized. Five isomers (the maximum possible) have been observed in the case of [Co(DFFT)(2)](-) in solution, as proved by H-1-NMR measurements. Although normally labile, complexes of Al3+([Al(DFFT)(2)](-)) have been separated by HPLC. In general, DFFTH2 forms kinetically inert complexes whereas complexes of NDFFTH2 tend to isomerize quickly in solution, as indicated by CD spectroscopy of separated HPLC fractions of [Cr(NDFFT)(2)](-).