Synthesis and characterization of dinuclear (Hedta)Ru(III) complexes with N-heterocyclic ligands: magnetic properties and DNA-binding studies

Abstract

Two ruthenium(III) complexes containing ethylenediaminetetraacetate(edta), viz. [{Ru(Hedta)} 2 L]· xH 2 O L = 4,4′-bipyridine(bpy) (1) and 4,4′-azopyridine(Azpy) (2), have been synthesized by the reaction between K[Ru(Hedta)Cl]·1.5H 2 O and the corresponding N-heterocycles. Complex 1 was determined by single-crystal X-ray diffraction. The products were characterized by IR, UV-vis, cyclic voltammetry, and magnetic techniques. Their DNA-binding activities were investigated using electronic absorption spectroscopic methods and fluorescence quenching; the experimental results show that these two ruthenium complexes may bind to CT-DNA through intercalation modes.

Synthesis, characterization and DNA-binding properties of Ru(II) complexes coordinated by ofloxacin as potential antitumor agents

“…Upon addition of CT DNA, the emission intensity in spectra of the complexes increased. These results may be attributed that the binding affinity increased in the sequence ofloxacin < 1 < 2 < 3, which is attributed to the hydrophobic and steric hindrance of the co-ligand [32]. These data also agree with the aforementioned study, indicating that the DNA-binding behavior is related to the antitumor activity of the Ru(II) complexes [33].…”

Synthesis and characterization of chiral ruthenium(II) complexes Λ/Δ-[Ru(bpy)2(H2iip)](ClO4)2 as stabilizers of c-myc G-quadruplex DNA

“…Intrinsic binding constants (K b ) of 1.97 and 1.18 × 10 5 M −1 were obtained for Λ-1 and Δ-1, respectively. The binding affinity of both isomers is comparable with that of [Ru(L)(bpy) 2 ]ClO 4 (L = (4-chloro-phenyl)-(1H-pyrrol-2-yl)-diazene and (4-nitro-phenyl)-(1H-pyrrol-2-yl)-diazene)[31,32], and higher than that of [RuX 2 (PPh 3 )L] (X = Cl, Br, L = 3-(benzothiazol-2-yliminomethyl)-naphthalen-2-ol)[33][34][35]. The binding of both isomers with c-myc G4 DNA has also been confirmed using ITC experiments and the results are listed in table 1.…”