metal-organic papers Acta Cryst. (2005). E61, m2055–m2057 doi:10.1107/S1600536805029776 Tam et al.  Fe(C 9 H 11 N 2 O 3 ) 3 2C 3 H 7 NO m2055 Acta Crystallographica Section E Structure Reports Online ISSN 1600-5368 Tris(2-N-methylaminocarbonyl-3-hydroxy-1,6- dimethyl-1,4-dihydro-4-pyridinonato)iron(III) dimethylformamide disolvate Tim F. Tam, a * Regis Leung- Toung, a Yingsheng Wang, a Michael Spino, a Glenn Williams b and Alan J. Lough c * a Medicinal Chemistry Department, ApoPharma Inc., 400 Ormont Drive, Weston, Ontario, Canada M9L 1N9, b RDD-Physical Properties, Apotex Inc., 400 Ormont Drive, Weston, Ontario, Canada M9L 1N9, and c Department of Chemistry, University of Toronto, Ontario, Canada M5S 3H6 Correspondence e-mail: ttam@apotex.ca, alough@chem.utoronto.ca Key indicators Single-crystal X-ray study T = 150 K Mean (C–C) = 0.003 A ˚ R factor = 0.047 wR factor = 0.126 Data-to-parameter ratio = 16.9 For details of how these key indicators were automatically derived from the article, see http://journals.iucr.org/e. # 2005 International Union of Crystallography Printed in Great Britain – all rights reserved In the crystal structure of the title compound, Fe(C 9 H 11 - N 2 O 3 ) 3 2C 3 H 7 NO, the Fe III ion is six-coordinate with a distorted octahedral configuration consisting of six donor O atoms from three bidentate ligands. Two of the amide NH groups are involved in intramolecular N—HO p (p = phenolic) hydrogen bonds, while the third is involved in forming centrosymmetric dimers via intermolecular N— HO p hydrogen bonds. Comment Iron chelation therapy is now a mainstay for the treatment of human conditions of iron overload, e.g. transfusion-dependent -thalassaemia (Cohen et al., 2004). At present, the bidentate 1,2-dimethyl-3-hydroxy-4-pyridinone ligand (L1; also known as CP20, deferiprone or Ferriprox) is the only oral iron chelator drug approved (in 48 countries) for -thalassaemic patients (Tam et al., 2003). However, L1 undergoes extensive metabolism in the liver, and more than 85% of the adminis- tered drug is recovered in the urine as the inactive 3-O- glucuronide. Hence, information on the structure of the ligand (L), as well as of the FeL 3 chelate, is important for the design of new bidentate Fe III -sequestering agents with better phar- macokinetic profiles. The single-crystal X-ray structures of Fe(L1) 3 (Charalambous et al. , 1988; Clarke et al. , 1992) and M(L1) 3 (M = Al and Ga; Nelson et al., 1988) have been reported previously. We report here the structure of the title compound, (I), an iron(III) complex of a related ligand, 2-N- methylaminocarbonyl-3-hydroxy-1,6-dimethyl-1,4-dihydro-4- pyridinone (L2). The structure of (I) is shown in Fig. 1, and selected bond lengths are given in Table 1. The Fe III ion is six-coordinate, Received 14 September 2005 Accepted 19 September 2005 Online 21 September 2005