Studies on the interaction of copper complexes of (−)-epicatechin gallate and (−)-epigallocatechin gallate with calf thymus DNA

Synthesis and characterization of the ligand based on benzoxazole and its transition metal complexes: DNA-binding and antitumor activity

“…Thus, it can be concluded that the interactions of all complexes towards CT-DNA follow the same order as the former experiments. Those significant changes indicate conformational changes and unwinding of DNA base pairs with destabilization of the DNA double helix, which is consistent with DNA intercalation binding mode suggested above [57]. The interaction of CT-DNA with the ligand has also been checked by CD spectroscopy (Fig.…”

Tuning the reaction products of ruthenium and ciprofloxacin for studies of DNA interactions

“…This observation allows the conclusion that there is a ground-state interaction between ct-DNA and 2. Earlier literature reports [10,18,22,38] point out that the observed red shifts are due to an intercalative interaction involving -stacking of aromatic chromophores of the ligands and the DNA base pairs. The spectra presented in figure 5(a) are consistent with this behavior.…”

“…All UV-Visible measurements were made twice. The variation of absorbance was monitored at 353 nm and the data was analyzed following the Benesi-Hildebrand method [10,22,23], equation (1):…”

“…The binding strength of 2 to ct-DNA was evaluated by calculating the intrinsic binding constant K b [10,22,23] which was obtained from the slope of the BenesiHildebrand plot (figure 5c). The observed value of K b ¼ 2.5 (AE 0.9) Â 10 4 mol À1 L suggests a strong interaction, in the same range observed for other ciprofloxacinate compounds [10].…”

Methyl thiophanate as a DNA minor groove binder produces MT–Cu(II)–DNA ternary complex preferably with AT rich region for initiation of DNA damage

“…The plot of F 0 /F vs. [Q] was not absolutely linear at higher complex concentrations and exhibited an upward curvature probably due to the high density of molecules in the system. Typically, the linearity of the Stern-Volmer plot suggests the (i) existence of one binding site for the ligand in the proximity of the fluorophore, or (ii) more than one binding site equally accessible to the ligand [32]. Thus, the gradual divergence from linearity of the Stern-Volmer plots on continuous addition of the ctDNA is suggestive of the presence of more than one binding site with different accessibilities and/or of the occurrence of combined static/dynamic quenching.…”