Synthesis and characterization of new complexes contain imine group and study their biological activity

Abstract

The current study comprises Synthesis, characterization and evaluation of the biological activity of three ligand of the transition metals Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II) , Zn(II) for the Schiff bases derived from Ciprofloxacin drug. This can be summarized as followed: The present study included the Synthesis of three ligands for Schiff bases Ll-3 ligands L1 from Ciprofloxacin condensation with Thiourea using the thermo escalation method and the absolute ethanol as a solvent. ligand (L2) was prepared from the Ciprofloxacin condensation with 2- aminobenzoic acid using the thermo escalation method and absolute ethanol as a solvent. Ligand (L3), on the other hand, was prepared from Ciprofloxacin condensation with Tryptophan using the thermo escalation method and the absolute ethanol as a solvent. The prepared ligands (L1-3) were characterized by using Infrared spectroscopy (FT-IR), Ultra-Violet spectroscopy (UV-Vis), Proton Nuclear magnetic resonance spectrum ( 1H-NMR), and Elemental Micro analysis for the elements(C.H.N), in addition to the measurement of the melting points. The resultant structural formula for the ligands was suggested . 21 complexes were prepared by the reaction i of Schiff base (L1- L3) with metal ions, 7 complexes for each ligand Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II) , Zn(II) with a molarity ratio (1:2) ion- first ligand (L1) and (1:1) ion-second and third ligand (L1, L2).The suggested figures for the prepared complexes were drawn by using the chemical program "Office Chem Draw professional 15.0. All complexes were characterized by the physical and spectroscopic measurement (Molar conductivity, Elemental analysis (C.H.N), Ultra Violet spectroscopy (UV), Infrared spectroscopy (FT-IR), Proton Nuclear magnetic resonance spectrum ( 1H-NMR) and the thermal analysis in addition of the magnetic susceptibility. This indicated that all the prepared complexes have a octahedral structure except the complexes of ligands (L3) [Cu (L3) (H2O)] and [Zn (L3) (H2O)] which have a tetrahedral structure. The antibacterial biological activity of the prepared ligands and complexes were carried out against two types of bacteria:  Escherichia Coli  Staphylococcus aureus The results showed that the prepared complexes has the high ability of inhibiting superior to that of the free ligands. While the complex (27,19) showed high ability of inhibition, and the complexes (7,8) showed low ability of inhibition against Escherichia Coli. bacteria The complexes (25,19) showed high ability of inhibition and the complexes (28,8) showed low ability of inhibition against staphylococcus aureus bacteria.