Interaction of catechin with an iron(III) bis-benzimidazole diamide complex

Bis-benzimidazole diamide ligand, 3,3'-thiobis-(N-((1H-benzo[d]imidazol-2-yl)methyl) propanamide [GBTPA = L] has been synthesized and utilized to prepare new Fe(III) complexes with exogenous anionic ligands, Cl ̄ and NO3 ̄ . The complexes have been characterized by IR, UV-visible, cyclic voltammetry, EPR and mass spectrometry. Low temperature EPR spectra are characteristic of a rhombic complex undergoing an axial distortion. Redox chemistry of catechin and iron(III) chloride complex in dimethyl sulfoxide, shows that catechin binds with Fe(III) complex leading to a considerable loss of antioxidant activity.