【作者】 赵淑敏；

【导师】 吴天星；

【作者基本信息】 浙江大学 ， 化学生物学， 2007， 博士

【摘要】 微量元素是生物体内所必需的营养元素之一，直接参与机体几乎所有的生理和生化过程，对生命活动起着极其重要的作用。它们参与生命机体组成，以酶的活化因子参与体内物质代谢，维持机体正常的生理功能和作为调节因子影响细胞复制和分化。微量元素在生物体内一般以配位化合物形式存在，它们主要以金属微量元素（如Fe、Cu、Zn等）为中心离子、以生物大分子（如糖类、蛋白质和核酸）为配体形成生物金属螯合物。目前国内外应用的有机微量元素添加剂均为二元配合物，如蛋氨酸锌，甘氨酸铁等。本文在二元配合物添加剂的研究基础上提出了三元配合物在微量元素添加剂领域的应用研究。由于金属配合物的结构和性质直接决定了微量元素在生物体内的作用机制，本文基于有机微量元素的配位结构和生物活性之间关系的研究基础，做了如下工作：（1）选择了4种传统必需微量元素（铜、锰、锌、钴）、1种新型必需微量元素镍、和1种可能必需微量元素镉为研究对象，选择2，5-吡啶二羧酸（H₂PYDC）作为酸性配体，分别以2，2’-联吡啶（bipy）、1，10-邻菲罗啉（phen）和苯并咪唑（bim）作为芳香氮碱配体，设计合成了25个有机微量元素配合物。（2）用元素分析、红外光谱、摩尔电导、电子光谱和X射线单晶衍射等方法对所合成的配合物进行结构表征。得到9个配合物的单晶解析结构。（3）用细胞生物学手段对所合成的配合物对HepG2和BRL细胞株进行活性筛选。通过实验，研究了配合物对细胞的增殖抑制作用、细胞形态结构以及对细胞株的毒性的影响。重点讨论了配合物的合成方法和条件对其结构的影响，针对目前所应用的有机微量元素配合物生物效价低以及元素之间的拮抗作用，提出三元配合物具有更多变的异构体结构和广泛的分子内配体之间和分子间的相互作用，对细胞株表现出比二元配合物更多样的作用机制。得到如下结果：（1）所合成的25个配合物具有多变、新颖的构型和广泛的分子内及分子间相互作用。中心金属离子呈现多四方角锥、八面体等多种配位构型和五、六等配位数，PYDC配体也呈现出螯合、桥连等多种配位形式，分子间存在芳环堆积、O-H…O氢键、N-H…O氢键以及三中心O-H…（O，O）氢键等相互作用，在空间，分子呈现出二维、三维等空间网络结构。（2）经细胞生物学筛选结果，所合成的25个配合物中有19个配合物具有生物活性，所合成的6个二元配合物均具有生物活性，6个三元配合物的活性强于其对应的二元配合物，分别为：三元锰配合物8的活性强于二元锰配合物5，三元钴配合物12的活性强于二元钴配合物9，三元锌配合物16活性强于二元锌配合物13，三元镍配合物18和20的活性强于二元镍配合物17，三元镉配合物25的活性强于二元镉配合物22。（3）有4个微量元素体系，即：锰配合物系列、钴配合物系列、锌配合物系列和镉配合物系列。其三元配合物体系（M-PYDC-bim）生物活性强于其相对的二元配合物（M-PYDC）。该论文对三元配合物作为有机微量元素应用的前景提供实验依据和理论推测。更多还原

【Abstract】 Trace elements are essential nutrients in biological bodies since they play critical roles in almost all the physiological and biochemical processes including active factors of enzymes and influence on reproduction of cell. Binding of metal trace elements to biological molecular ligands construct to chelate in bodies. The activities of organic trace elements are all binary complexes both at home and abroad, such as zinc-methionine and iron-glycine etc. Based on the above theory, the ternary complexes are used in nutritional additives field. The biological activities of complexes are determined by their structures. The main works in this thesis are as follows:1. Four traditional essential trace elements (copper, manganese, zinc, cobalt), one novel essential trace element(nickel) and one potentially essential trace element are chosen as central ions, 2, 5-pyridine dicarboxylic acid, 2, 2’-bipyridine, 1, 10-phenanthroline and benzimidazole are chosen as ligands.2. The structures of these complexes were characterized by elemential analysis, infrared spectra, molar conductance, electronic spectrum and x-ray diffraction methods. Nine crystal structures are determined by x-ray diffraction.3. The biological activities of these complexes were studied by cell culture method. HepG2 and BRL cell strain are used to determine the influence of these complexes on cell proliferation, morphology and toxicity.The methods and conditions were discussed which may influence the structure of complexes. Ternary complexes may have more effects on the cell for they have two ligands and therefore the higher bioavailability and lower antagonism of trace elements are expected. The results are as follows:1. These complexes have variable coordination geometry, intramolecular and intermolecular interaction. For example, some central ions are five-coordinated while some are six-coordinated; some complexes are square-pyramidal while others are octahedral; the PYDC ligand shows chelate and bridge forms; three kinds of hydrogen bonds in complexes(O-H…O, N-H…O and bifurcated O-H…(O, O)) andπ-πinteraction are also found in some complexes; there are two kinds of hydrogen bond network (2D and 3D).2. 19 complexes have biological activities and 6 ternary complexes are better than corresponding binary complexes. In detail, manganese complex 8 is better than manganese complex 5, cobalt complex 12 is better than cobalt complex 9, zinc complex 16 is better than zinc complex 13, nickel complex 18 and 20 are better than nickel complex 17, cadmium complex 25 is better than cadmium 22.3. The biological activities of the ternary M-PYDC-bim complex are better than binary M-PYDC complex in four trace elements series. They are manganese series, cobalt series, zinc series and cadmium series.In general, the thesis will provide experimental basis and academic presume for utilization of ternary complex in additive field.更多还原