In this study, novel ligand Schiff base complexes derived from Gabapentin drug (L 1 =[C 20 H 23 NO 3 ]) and Cu(II), Zn(II) and Ni(II) as well as asymmetric ligand Schiff base derivative of diphenylamine (L 2 =[C 20 H 17 N 3 O 2 ]) complex with Co (II) have been synthesized and characterized by various spectroscopic techniques such as electron spectroscopy UV-Vis, X-ray crystallography, mass spectrometry, LC-mass, FT-IR, elemental analysis, 1 H and 13 C NMR spectroscopy in the first part. The interactions of L 1 ligand and all synthesized complexes with CT-DNA (calf thymus) macromolecules have then been studied using spectroscopic techniques. The binding of L 1 ligand and Cu (II), Zn (II) and Ni (II) complexes with CT-DNA was of partial intercalation and that of Co (II) with CT-DNA was a minor groove interaction. In addition, the study of the interaction of these compounds with BSA (bovine serum albumin) using fluorescence spectroscopy showed that the quenching mechanism was of static type. Molecular docking studies of Co (II), Zn (II) and Ni (II) complexes with CT-DNA and BSA were performed and the results showed good agreement with experimental results. Furthermore, antitumor activity and toxicity of all compounds with a number of cancer cell lines (JURKAT, SKOV3 and U87) were examined by MTT assay in vitro and compared with cisplatin and the IC 50 values indicated favorable inhibition of cancer cells. In the third part, the interaction of Co (II) complex with MMT-K10 commercial nano clay was studied using TEM, FE-SEM, TGA/DTA and XRD analyses and the results showed the appropriate net thermal resistance of this combination compared with MMT-K10. Antibacterial bioinformatics computation of this combination along with ligand L 2 in the in silico environment indicated non-degradation and antibacterial features of Co (II) complex unlike L 2 ligand. In the fourth part, Zn (II) and Ni (II) complexes were fixed on TiO 2 nano particle by calcination at 450 °C. NiO/TiO 2 and ZnO/TiO 2 metal oxides were prepared and analyzed by TEM, FE-SEM, TGA/DTA and XRD and their photocatalytic activities in the degradation of methylene blue pigment were examined. NiO/TiO 2 nano metal oxide showed a higher photocatalytic activity than pure TiO 2 and ZnO/TiO 2 nanoparticles .
