【作者】 陈艳君；

【导师】 高坤； 孙文华；

【作者基本信息】 兰州大学 ， 有机化学， 2009， 博士

【摘要】 菊科（Compositae）大丁草属（Gerbera）植物,全球近80种,我国有20种,绝大部分集中于西南地区。其中有2种长期入药,具有清热解毒、抗菌消炎、化痰止咳、利尿活血之功效。石上大丁草[Gerbera saxatilis Chang ex Y.C.Tseng]为大丁草属中的一种,产于四川,生于石上。菊科（Compositae）蟛蜞菊属（Wedelia）植物,全世界约60余种,主要分布于热带和亚热带地区。我国有5种,主要产于东南至西南部各省区。该属植物在许多国家作为民间药,具有保肝利胆、抗病毒、抗炎等功效。三裂叶蟛蜞菊（Wedelia trilobata）为菊科（Compositae）蟛蜞菊属（Wedelia）植物,多年生草本。本论文上篇系统研究了两种菊科植物的化学成分及部分化合物的生物活性。采用常规柱层析（CC）、制备薄层层析（PTLC）、重结晶等手段分离得到36个化合物,并利用各种现代波谱技术(IR,EI-MS,HR-ESI-MS,¹H-NMR,¹³C-NMR,DEPT,NOSEY,¹H-¹HCOSY,HMBC,HSQC)以及X-ray单晶衍射方法,确定了其中35个化合物的结构,其中7个为新化合物。从石上大丁草中分得30个化合物,其中6个为新化合物:从三裂叶蟛蜞菊中分得6个化合物,其中1个为新化合物。我们还对分离得到的香豆素类化合物进行了活性实验,采用SRB法,测试了其对人急性早幼粒白血病细胞（HL-60）,人肝癌细胞（SMMC-7721）和人宫颈癌细胞（HeLa）的抑制活性。对石上大丁草以及三裂叶蟛蜞菊化学成分的研究有望为中草药活性成分及其构效关系的研究、药理学、植物化学分类学和新药筛选提供相关的科学依据,为我国天然资源的利用与开发提供帮助。论文上篇最后对香豆素类化合物抗HIV活性研究进展进行了综述。本论文下篇主要致力于亚胺基苯并咪唑型过渡金属（铬、铁、钴和镍）配合物设计与合成,以及它们在催化乙烯齐聚和聚合中的应用。在含铝助催化剂的活化作用下,研究了这些配合物的乙烯催化性能。对配体环境,包括取代基的电子效应和立体效应等,以及各种催化反应条件（如温度、Al/M摩尔比、压力等）进行了系统的研究,考察了它们对催化活性和催化产物性质的影响。主要包括以下两个部分:第一部分:合成并表征了一系列基于亚胺基苯并咪唑吡啶的具有变形八面体几何构型的铬配合物。在改性甲基铝氧烷（MMAO）的作用下,这些配合物都表现出中等或高的齐聚和聚合活性,并且齐聚产物分布较宽从C₄到C₃₆,一些配合物还得到了特殊分布的齐聚产物（C₆含量很低）。多数情况下,聚乙烯为催化反应的主产物,齐聚物中也是以高碳数烯烃为主。所得聚乙烯经鉴定为末端乙烯的长链的烯烃。聚合反应条件、配体的立体效应和电子效应对催化活性都有很大影响。第二部分:合成了一系列基于亚胺基苯并咪唑吡啶配体N^N^N的铁（Ⅱ）、钴（Ⅱ）以及镍（Ⅱ）配合物,并对它们的结构进行了表征。通过对这些配合物的乙烯催化研究发现,在合适的条件下,这些配合物表现出中等的催化活性。更多还原

【Abstract】 About 80 species belong to the genus Gerbera（Compositae） in the world,of which 20 are distributed in China,mainly in the southwest;only 2 species have been used as Chinese folk medicines with the efficacy of reliving internal heat, antibiotic,reducing phlegm and a cough,invigorating the circulation,diuresis. Gerbera saxatilis is a species of genus Gerbera,which grows on the stone in the Sichuan Province.The Wedelia,consisting of 60 species,is one of the genus in the family Compositae and perennial herbs.The species of Wedelia are mainly distributed in tropical and semitropical zone with 5 species in the southeast and southwest of China.In many countries,the species of Wedelia have long been used for folk medicines with liver protecting,choleretic,antivirus and antiphiogistic efficacy. Wedelia trilobata is a species of genus Wedelia.In the first part of this dissertation,the chemical constituents and their bioactivities of two Compositae species were studied.The chemical constituents were isolated by means of general silica gel column chromatography（CC）, preparative thin layer chromatography（PTLC）,and recrystallization etc.The structures of these compounds were elucidated by spectroscopic methods,including IR,EI-MS,HR-ESI-MS,¹H-NMR,¹³C-NMR,DEPT,NOSEY,¹H-¹H COSY, HSQC,HMBC,and single-crystal X-ray crystallography.From Gerbera saxatilis,30 compounds were isolated,6 of them are new including 3 benzofuran and 3 coumarin derivatives.From Wedelia trilobata,6 compounds were isolated,1 of them is a new entkaurane-type diterpene. Furthermore the bioactivities of some coumarins were studied,using SRB method to evaluate their cytotoxic activity against human leukemia HL-60 cell,human hepatoma SMMC-7721 cell and human cervical carcinoma HeLa cell.The results would be a supplement for the research on bioactivity of chemical constituents in traditional Chinese medicine,helpful reference for pharmacology, chemotaxonomy and screening new medicines,and may benefit utilizing and developing the natural resources of our country.Finally,recent progress in the development of coumarin derivatives as potent anti-HIV agents was reviewed in this part.The second part of this dissertation focuses on designing and synthesis of benzimidazolyl transition metal complexes as catalysts for ethylene activation.Upon activation with aluminum compounds,these complexes are active for ethylene oligomerization and/or polymerization.The relationship between the ligand environment and the catalytic activity were elucidated.Additionally,the reaction parameters,such as the reaction temperature,cocatalyst,the amount of cocatalyst and ethylene pressure were systemically studied.Two parts are included in this part as follows:PartⅠ:A series of N^N^N chromium（Ⅲ） complexes complexes ligated by 2-imino-6-benzimidazole pyridyl ligands was synthesized and characterized.X-ray crystallographic analysis reveals that the geometry around the chromium atom is octahedral.These tridentate chromium complexes afforded moderate to high activity for ethylene oligomerization and polymerization with broad oligomer distributions from C₄ to C₃₆ and some complexes got special distributions of oligomers.In most cases,polyethylene was the main product and higher carbon number olefins usually accounted for the majority of the oligomers.The obtained polymers were confirmed to be vinyl-terminal long-chain alkenes.Reaction conditions including cocatalyst, temperature,ethylene pressure and reaction time were found to have significant influences on the catalytic behaviors.PartⅡ:The late transition metal complexes bearing pyridyl benzimidazole ligands were also prepared.Upon treatment with suitable cocatalyst,these complexes showed moderate catalytic activities.更多还原