Synthesis, spectroscopic characterization and study the effect of gamma irradiation on VO2+, Mn2+, Zn2+, Ru3+, Pd2+, Ag+ and Hg2+ complexes and antibacterial activities

Novel complexes of VO2+, Mn2+, Zn2+, Ru3+, Pd2+, Ag+ and Hg2+ have been prepared by reacting their metal salts with ligand, named (4-(4-chlorophenyl)-1-(2-(phenylamino) acetyl) thiosemicarbazone). Study of synthesized metal complexes was confirmed by different analytical and spectral techniques (H-1 NMR, MS, FT-IR, UV-Vis, EPR and Powder X-ray diffraction), thermogravimetric studies as well as molecular modeling. FT-IR spectra showed that the compound behave as neutral or monobasic tetradentate. In case of complexes of Mn2+, Zn2+, Ag+ and VO2+, through (N2-H), (C=O) or (C=O) groups. While, the ligand behave as neutral bidentate in case of complexes with Pd2+ and Hg2+. X-ray diffraction pattern of Mn2+, Pd2+ and Ag+ complexes before and after irradiation are recorded. XRD studies exhibited that decrease in the crystalline size of sample Mn2+ as compared of samples Ag+ and Pd2+ upon irradiation and irradiation influenced the crystallinity of the complexes. The possible structures of the ligand, Mn2+, Pd2+ and Hg2+ complexes have been computed by means of the molecular mechanic calculations using the hyper chem. 8.03 molecular modeling program. The bond length, bond angle, HOMO, LUMO and dipole moment have been studied to verify the geometry of Mn2+, Pd2+ and Hg2+ complexes. The effect of gamma irradiation was investigated by recording the new results of pervious spectroscopic techniques and other measurements. Thermal studies of these chelates before and after c-irradiation showed that the complexes after c-irradiation were more thermally stable than before c-irradiation. The compound and its metal complexes have been experienced for their inhibitory outcome on the growth of microorganisms against gram positive and gram negative. The results proved that the complexes B-1-B-7 have potent antibacterial activity as compared to that of ligand. (C) 2019 Production and hosting by Elsevier B.V. on behalf of King Saud University.