Synthesis, characterization and DNA binding studies of organoantimony(V) ferrocenyl benzoates

Organoantimony(V) ferrocenyl benzoates (OFBs) [p-(C5H5FeC5H4)C6H4COO]2SbR3 (R = C6H5, p-CH3C6H4) (3, 4) and [m-(C5H5FeC5H4)C6H4COO]2SbR3 (R = p-CH3C6H4) (5) were synthesized and characterized by FT-IR, 1H and 13C NMR, single crystal XRD and elemental analysis. The DNA interaction of the complexes (3–5) was investigated by UV–Vis spectroscopy and cyclic voltammetry (CV). The complex-DNA binding constant was found to vary in the sequence: K2 (4.80 × 105) > K1 (2.36 × 104) > K3 (1.87 × 104) > K4 (6.61 × 103) > K5 (6.58 × 103). The shift in peak potential, current and absorption maxima of OFBs in the presence of DNA revealed that CV coupled with UV–Vis spectroscopy could provide a convenient way to characterize complex-DNA interaction mechanism, a prerequisite for the design of new anticancer agents and understanding the molecular basis of their action.