Synthesis, Characterization And Biological Properties Of The Pendant-armed Polynitrogen Macrocyclic Complexes

This dissertation uses the novel symmetric polynitrogen-macrocyclic complexes with pendant-arm as research objects, focusing on the synthesis, characterization, modeling metalloenzyme, cleavage of DNA pBR322 and activity against the test bacterial organism of them. Aim to synthesize highly effective novel enzyme catalyzers and bactorial inhabitors, six new complexes, [Mn₂H₂L¹(OAc)₂](ClO₄)₂·(H2O) 1, [Ni₂L²(OAc)](ClO₄)·(CH₃OH) 2, [Ni₂L³(OAc)](ClO₄)·2(CH₃CN) 3, [Ni₂L⁴(OAc)](ClO₄)·2(CH₃CN) 4, [Cu₂L³(OAc)](ClO₄)·(CH₃CN) 5 and [Cu₄L³(OAc)₂O₂](ClO₄)·(CH₃CN) 6, have been synthesized and characterized by element analyses, mass spectra, IR, ¹HNMR and X-ray diffractions techniques. The electro-chemistry characterization and magnetism interactions between metal ions of three complexes have been studied by the measurements of cyclic voltammograms and variable-temperature magnetic susceptibility. In addition, Catalase-like activity of disproportionating H₂O₂ into H₂O and O₂ of the dinuclear manganese(â…¡) complex 1, and the cleavage activity of plasmid DNA pBR322 and the inhabitory bacteria activity of the complexes 1,2,4 have been also investigated.The work is composed of:1. N, N-bis(3-aminopropyl)-2-pyridylmethylamine hydrochloride and N, N-bis(3-aminopropyl)-2-benzylmethylamine have been prepared from 2-pyridylmethylamine and 2-benzylmethylamme, respectively and characterized by IR and ¹HNMR.2. The novel pendant-armed unsymmetric dinuclear manganese macrocyclic complexes with a big cavity has been synthesized firstly. The X-ray diffraction result of the complex reveals that the two nitrogen atoms of the two pendant arms exhibit trans- coordination mode with two metal ions , and the two imine N and one phenol O are not coordinated with metal ions, which leads to the formation of the big cavity. Electrochemistry study shows that the complex behaves two pair of pseudo-reversible redox peaks in the range of potential 0--1.8 V. The experimental data of susceptibility of the complex indicates weak antiferromagnetic exchange interactions between the two manganese (â…¡) in the complex. The record of oxygen volume produced by decomposition of H₂O₂ displays the relatively high efficiency of the complex 1, and the active intermediates Mn^â…¡Mn^â…£(=O)H₂L¹(OAc)₂ is quite probably occurred from the visible spectrum of process. The results of gel electrophoretic separations of plasmid pBR322 DNA induced by the complex shows it can not cleave basically pBR322, but in the presence of H₂O₂, complex 1 has obviously cleaving effect and can convert Formâ… plasmid DNA into Formâ…¡or Formâ…¢gradually, and make it disappeared finally. These complexes have antibiotic activities for Escherichia coli.3. Two symmetric dinuclear nickel macrocyclic complexes with pendant arm containing thiophenol group 2 and 3 and one with benzyl pendant arm 4 have been synthesized by template reactions. The X-ray diffraction results of complexes show that shape of ligands are all like a saddle and two metal ions are bridged byμ₂-acetato in three complexes, and the S atoms on thiophenol group of pendant arm in complexes 2 and 3 are not involved in coordination. The CVs of the complexes show only one pseudo-reversible Ni^{â…¡/â…¡} and Ni^{â… /â…}  waves. Magnetic susceptibility measurements of complex 2 and 3 reveal an anti-ferromagnetic interaction between two metal ions. The DNA cleavage ability of two complexes 2 and 4 with different pendant arm is poor. The tests of antibacterial activity of the two complexes toward Escherichia coli have been performed, and the experimental show they have ability of bacteriostasis.4. The symmetric macrocyclic ligand has been synthesized by condensation reaction between 2, 6-diformyl-4-chlorophenol and N, N-bis(3-aminopropyl)- 2-pyridylmethylamine. Reacting this ligand with copper(â…¡) in different proportion, one tetranuclear and one dinucelar copper(â…¡) complexes have been obtained, respectively. The analyses of the crystal structures show that the Cu₄O₄ core of of complex 5 is in "chair" shape, and the cation of complex 6 is in "saddle" one. The coordination environment of two copper(â…¡) metal ions in complex 6 is similar to thoseof two nickel(â…¡) metal ions of above-mentioned three complexes.