【作者】 杨莉宁；

【导师】 张逢星；

【作者基本信息】 西北大学 ， 材料化学， 2012， 博士

【摘要】 硝基咪唑类药物是常见的抗厌氧菌类药物,尤其甲硝唑药物在临床上的应用非常广泛。但随着时间的推移,细菌的耐药性迅速增加,药物的毒副作用也凸显出来,因而对硝基咪唑类药物的构效关系的研究在日益深入,新的硝基咪唑类药物也在不断的开发之中。近年来的研究结果表明,由于配体和金属离子之间的协同作用,当具有生物活性的有机药物与金属离子形成配合物后,其药理活性有增强的趋势。鉴于此,本文在合成一系列硝基咪唑衍生物的基础上,得到了它们的过渡金属配合物,采用紫外光谱、荧光光谱、黏度法等手段初步研究了这些硝基咪唑类药物及其过渡金属配合物与小牛胸腺DNA的相互作用,测试了所合成的硝基咪唑类药物及其Cu、Ag配合物的抗厌氧菌生物活性,分析了化合物和与DNA相互作用之间、抗菌性与化合物之间的构效关系,以达到定向合成的目的,对开发更有效的抗菌药物有一定的借鉴作用。论文主要内容为：1.合成了六种硝基咪唑类衍生物：刚性的联咪唑单硝基衍生物、二硝基衍生物L2,N,N’-二甲基-5-硝基联咪唑L3,柔性的甲硝基双咪唑乙烷L4、甲硝基双咪唑丙烷L5和甲硝基双咪唑丁烷L6,通过元素分析、紫外、红外、熔点测定等方法对其进行了性质表征。2.主要以甲硝唑L1和合成的L2-L6硝基咪唑衍生物为配体,以人体必需的微量金属元素Cu(Ⅱ), Ag(Ⅰ), Co(Ⅱ), Ni(Ⅱ), Zn(Ⅱ), Mn(Ⅱ)等为中心原子,合成了23种过渡金属配合物,并以5-磺基水杨酸为辅配体,以联咪唑、单甲基联咪唑、L4为主配体,合成了3种三元混配金属配合物。采用元素分析、紫外、红外、电导率、差热-热重分析等方法确定这些配合物的化学组成,得到了4种Cu配合物和1种Ag配合物的单晶,通过单晶X-射线衍射方法对其进行了结构表征和分析。这5种配合物单晶的结构涵盖了单核、双核、一维链聚合物三种类型。3.通过紫外光谱、荧光光谱、黏度测定等方法系统地研究了甲硝唑和所合成的硝基咪唑类有机配体及其过渡金属配合物与小牛胸腺DNA相互作用模式。化合物与DNA相互作用构效关系研究表明：配体主体结构的平面性和平面面积等特点对化合物与DNA相互作用起决定性影响。4.采用经典的二倍稀释法药物敏感试验,研究了甲硝唑和所合成的5种配体及其12种Cu,Ag配合物、Cu(Ⅱ)盐、Ag盐对两种厌氧菌：变形链球菌UA159和伴放线放线杆菌ATCC29523的抑菌活性。从中发现了一种比甲硝唑抗厌氧菌效果更好、广谱抗菌的硝基咪唑衍生物—N,N’-二甲基-5-硝基-2,2’-联咪唑L3,认为其值得进一步深入研究开发。构效关系表明,取代基硝基的位置,给电子基团甲基是否存在,双杂环的刚性与抗厌氧菌的生物活性都可能存在着一定的联系。上述工作不仅使无机药物化学的研究内容更加丰富,而且为高效、低毒的无机抗厌氧菌药物的设计与合成提供了非常有价值的参考资料。更多还原

【Abstract】 Nitroimidazole drugs are valuable drugs for treating infections due to anaerobic bacteria, especially metronidazole drugs have been applied in clinic extensively. As time goes on, strains of bacteria increase quickly and the side effects of drugs have been raised recently. So the structure-activity relationships of nitroimidazole drugs have been well studied, in the same time, the synthesis of novel biologically active nitroimidazole derivatives seems to be in the continuous development. The recent research results indicate the inhibitory activity of the metal complex will increase because of the cooperation between the metals and ligands. In view of this, here in, on the basis of the synthesis of a series of nitroimidazole derivatives, we selected them as ligands to synthesize their transition metal complexes, characterized their crystal structures and properties. By the ultraviolet spectrum, fluorescence spectra, viscosity methods, the interaction of nitroimidazole derivatives with DNA and the factors which effect interaction of nitroimidazole derivatives with DNA also have been studied. Meanwhile the interaction between nitroimidazole derivatives’Cu and Ag metal complexes and DNA were studied by spectroscopy and viscosity methods. In addition, their antiamoebic activity has been determined in order to achieve the purpose of directional synthesis and this work will be of certain reference to develop more effective antimicrobial drugs.The paper is composed of following parts:1. Six novel nitroimidazole derivatives, rigid4-Nitro-2,2’-biimidazole,4-Nitro-2,2’-biimidazo(L2), N,N’-Dimethyl-5-nitro-2,2’-biimidazole(L3), and flexible ligands1,2-di-[1-(2-methyl-4-nitroimidazolyl)]ethane (L4),1,3-di-[1-(2-methyl-4-nitroimi-dazolyl)]propane (L5),1,4-di-[1-(2-methyl-4-nitroimidazolyl)]butane(L6) have been synthesized and characte-rized by UV, IR, melting point determination and elemental analyses.2. Twenty-three complexes have been synthesized by reaction of above novel nitroimidazole derivatives, metronidazole with Cu(Ⅱ),Ag(Ⅰ),Co(Ⅱ),Ni(Ⅱ),Zn(Ⅱ),Mn(Ⅱ) salts respectively. Moreover, reactions of H2biim, MeHbiim or L4in the presence of Cu2+or Ag+as central ion and5-sulfosalicylic acid as auxiliary ligand gave three complexes. Most of complexes have been characterized by elemental analysis, UV, IR spectroscopy, TG-DTA and molar conductivity. X-ray single crystal diffraction analysis reveal that five complexes belong to mononuclear, binuclear complex and1-D chain coordition polymer respectively.3. The interaction mode between ligands, complexes and calf thymus DNA has been investigated by means of UV, fluorescence spectra and viscosity measurements. The structure-activity relationship of these compounds binding to DNA has been examined and the results indicate that the planarity and the plane surface area of the main structure of compounds are decisive influence to DNA interaction.4. With the two-fold agar dilution method, the antiamoebic activities of five nitro-imidazole derivatives, metronidazole, their copper, silver complexes and copper, silver salts have been determined, respectively. It has been found that N,N’-Dimethyl-5-nitro-2,2’-biimidazole(L3) has better effect of antiamoebic activity than metronidazole and the L3is worth further research and development. Structure-activity relationship of these compounds reveal that there is a possible link among the nitro position, methyl groups, double heterocyclic rigid of compounds and the effect of their antiamoebic activity.The researches of the paper not only enriched the content of inorganic medicinal chemistry, but also supplied valuable information for design and synthesis of inorganic antiamoebic drugs with high activity and low toxicity.更多还原