Novel Nano Copper Complexes of a New Schiff Base: Green Synthesis, a New Series of Solid Cr(II), Co(II), Cu(II), Pd(II) and Cd(II) Chelates, Characterization, DFT, DNA, Antitumor and Molecular Docking Studies

A new series of solid Cr(II), Co(II), Cu(II), Pd(II), and Cd(II) chelates of the 1-((E)-(2-mercaptophenylimino)methyl)naphthalen-2-ol (H2L) Schiff base ligand were synthesized and characterized by different analytical and spectroscopic techniques. The results revealed the geometry around central metal ion to be tetrahedral for Cr2L2, Co2L2, Cu2L2, and Cd2L2 complexes and square planar geometry around Pd2L2 complex. 3D modeling of the ligand and its metal complexes was obtained using DFT/B3LYP method with LANL2DZ basis set. Also quantum-mechanical properties like molecular orbitals and molecular energies were calculated. The Cu nano complexes were prepared in different media Spinacia oleracea (SO), Corchorus olitorius (CO), Coriandrum sativum (CS), Eruca sativa (ES), and Anethum graveolens (AG) extract in EtOH. The particle size of the nano coordination Cu complexes depends on the high concentration of reducing agent present in the green leaf extract. The nature of the newly nano sizEd Cu complexes prepared in different media as crystalline or amorphous and particles size was determined by X-ray diffraction (XRD); scanning electron microscope (SEM). The Cu nano complexes are characterized by spectroscopic and thermal analysis techniques before heating and after heating upon 200 degrees C. The Cu nano complexes were showed an antitumor activity towards hepatocellular carcinoma cell line (HepG-2). The antitumor data revealed that the Cu nano complex prepared in CS/EtOH (IC50 similar to 4.9 mu g ml(-1)) has antitumor activity nearly to the activity of cis-platin (IC50 similar to 1.143 mu g ml(-1)). The DNA cleavage study showed that the ability for the screened Cu nano complex prepared in CS/EtOH to cleavage DNA. Therefore, it may be used as antitumor drugs in vivo to prevent the DNA replication in the tumor cells and to suppress the cancer for further increasing. Docking studies of the ligand and its Cu(II) complex showed good binding energy score ranging from (-4.73 to -5.98 kcal mol(-1)).