Syntheses, crystal structures, DNA binding, DNA cleavage and DFT study of Co(iii) complexes involving azo-appended Schiff base ligands†
Abstract
Herein, we have reported three new Co(III) complexes involving azo-appended Schiff base ligands. All three complexes were characterized using different spectroscopic tools like NMR, FTIR and UV-Vis. The structures of the complexes 1–3, were confirmed by single crystal X-ray diffraction analysis. DFT and TDFFT computations were performed to support the structural and electronic parameters of the complexes. Computed bond distances and angles well resemble those of X-ray data. Absorption and viscometric titration studies revealed that each of these octahedral complexes interacts with CT DNA to result in minor groove binding. The intrinsic binding constants (Kb) were calculated to be 7.90 × 105, 1.35 × 105 and 1.075 × 105 M−1, respectively, for complexes 1–3. Complexes 1–3 also exhibited oxidative DNA cleavage activity in the presence of hydrogen peroxide.