Two novel homo/hetero polynuclear complexes for DNA binding, molecular docking and anti-cancer activity

Two novel polynuclear complexes [CuL(MeOH)]2Cu (1) and [CuL(OH2)]2Ni (2) were synthesized using a mononuclear copper complex (Na[CuL], where H3L = [N-(2-carboxy-4-fluoro-benzyl)-N-(3-dimethylamino) propyl] oxalamide) as the ligand and characterized by Fourier transform infrared (FTIR) spectroscopy, Mass spectrometry analysis (MS) and X-ray single crystal diffraction techniques. The two complexes have similar structures in which the copper atom in the [CuL(MeOH)] and [CuL(OH2)] moieties is in a square pyramidal environment, while the central Cu or Ni atom is in a square planar environment coordinated by two oxygen atoms from each of two L ligands. In complex 1 the three metal ions are linear, while in complex 2, the Cu...Ni... Cu angle is slightly bent with the terminal Cu...Cu distances being 10.398 & Aring; and 10.345 & Aring;, respectively. Further Cu...O and Ni...O interactions link complex 1 into a 1D polymers and complex 2 into a hexanuclear dimer. The interaction mode between the polynuclear complexes and DNA was studied using electron absorption spectroscopy, fluorescence spectroscopy and viscosity techniques. Furthermore, molecular docking techniques were also used to calculate the interaction strength and modes, and the results showed that the interaction mode was intercalation mode. The MTT results indicated that the complexes could kill MCF7 cells and therefore had certain anti-cancer activity.