2015 Volume 14 Issue 2 Pages 23-29
Some iron(III) complexes, including [Fe2(μ-O)(nta)2(H2O)2]2– (1), [Fe2(μ-O)(edda)2(H2O)2] (2), and [Fe2(μ-O)(ida)2(H2O)4] (3), are considered to be carcinogens causing renal injuries according to the results of previous animal experiments, where nitrilotriacetate [(nta)3–], ethylenediamine-N,N'-diacetate [(edda)2–], and iminodiacetate [(ida)2–] are the chelating ligands (chelators). On the other hand, a similar iron(III) complex [Fe2(μ-O)(pac)2(H2O)2] (4) is not considered to be a carcinogen, where N-(2-pyridylmethyl) iminodiacetate [(pac)2–] is the chelating ligand. In order to clarify the differences in carcinogenicity, the structures of complexes 1–4 were investigated based on the density functional theory (DFT) method, because the structures of complexes had not been clarified in solution. As a result, two-point interaction with hydrogen peroxide or α-helix was found to be possible for carcinogenic iron(III) complexes 1 and 3, whereas the interaction was found to be impossible for non-carcinogenic iron(III) complex 4.