【作者】 龙海林；

【导师】 秦海林；

【作者基本信息】 北京协和医学院 ， 药物化学， 2014， 博士

【摘要】 中药黄芩为唇形科多年生草本植物黄芩Scutellaria baicalensis Georgi的根,是一种临床常用的中药,其药用历史悠久。通过查阅和调研大量文献发现,目前国内外学者已经对黄芩进行了大量研究,包括化学成分和药理药效研究。黄芩的主要成分是黄酮类化合物,据文献报道还含有少量的苯乙醇糖苷、萜类和挥发油类。为了从天然有机化学的角度深入研究天然药物的组成特征以及这种组成特征在药用植物基源鉴定方面的应用,并尽可能地在黄芩中发现黄酮类化合物之外的其它有效成分,更深入地研究常见中药的活性物质与功能,本论文对中药黄芩的根进行了系统的化学成分研究。本论文运用多种色谱分离方法和波谱技术,对黄芩进行了系统的化学成分研究,从黄芩的80%乙醇提取物中分离得到102个化合物,鉴定了95个化合物,发现新化合物18个(1*-13*,16*-20*)。所鉴定化合物包括黄酮类化合物61个,香豆素类1个,二萜类2个,联苯类3个,二苯乙烯类2个,苯乙醇苷类8个,苯甲醇苷类2个,木脂素类6个,其它类化合物10个。化合物编号、名称与结构如Table1和Figure1所示。首次在黄芩中发现香豆素、二苯乙烯和木脂素类化合物,包括两个7,9’：7’,9型双环氧木脂素(化合物14和20*),丰富了黄芩的化学成分研究。根据黄芩的民间用药特点和相关文献查阅,发现黄芩具有广泛的药理活性,为了进一步发掘黄芩药材及其化学成分的活性,本论文对黄芩粗提物和分离得到的部分单体化合物进行了活性筛选,采用多种药理模型进行了活性初步研究,结果如下：(1)对黄芩提取物醇提物、石油醚部位、乙酸乙酯部位、乙酸乙酯碱部位、正丁醇部位、正丁醇碱部位和部分单体化合物进行了破骨细胞抑制活性的初步研究,结果发现粗提物正丁醇碱部位和三个单体化合物(化合物11,14和化合物84)在体外实验中显示一定的破骨细胞抑制活性；(2)对黄芩部分单体化合物进行乙酰胆碱酯酶和丁酰胆碱酯酶抑制活性筛选,结果未发现活性较好的单体化合物；(3)对部分化合物进行抗肿瘤活性筛选,未发现活性较明显的化合物；(4)对黄芩部分单体化合物正在进行高通量活性筛选,正待获取有关筛选结果。对缺少植物形态学和组织学鉴别特征的中药及其制成品的基源鉴定和质量控制研究一直是中药研究中具有挑战性的研究内容。通过采用植物化学的研究方法表达中药化学组成的整体特征,最终达到中药及其制成品的基源鉴定的目的已经成为该研究领域的共识。本论文在对黄芩化学成分研究的基础上,采用规范化程序进一步探讨了来自八个不同产地的黄芩样品的专属性特征对照物质(Extact-NP部分和Extract-P部分)的HNMR和HPLC指纹分析方法。通过将单体化合物与各个产地样品的HNMR和HPLC图谱进行对照,完成了八个产地黄芩Extract-NP和Extract-P的HNMR和HPLC指纹图谱特征信号的解析。结果表明,八个产地的不同种黄芩显示有共同的指纹图谱信号，既有一致性也有不同之处，可以用于黄芩药材的基源鉴定。此法具有操作规范、简单、专属性强的特点，可作为不同中药材基源鉴定的参考操作方法。更多还原

【Abstract】 Scubellaria baicalensis from the family Scutellaria is one of the crude drugs in Traditional Chinese Medicine (TCM). The crude roots of S. baicalensis exhibit various therapeutic functions in the definition of TCM, such as the activities of the treatment of inflammation and the anticancer properties, among others. From the literature, about100compounds have been isolated from S. baicalensis in the field of phytochemistry which indicated that flavonoids are the major native chemical constituents. In the meantime, phenylpropanoid glycosides, diterpenoids, and styrenes, etc. have also been isolated from S. baicalensis. In order to find more active substance and functions of the natural medicine, this thesis studied the chemical constituents of the roots of S. baicalensis systematically.By using a variety of chromatographic techniques and spectroscopic methods,102compounds were isolated from the80%aq. ethanol of the roots of S. baicalensis, with95ones of which being identified in this dissertation. Names and structures of the purified compounds are listed in Table1and Figure1, respectively. Among them,18ones, i.e., compounds1*-13*and16*-20*, are new compounds, with compounds1*-7*being flavonoids; compounds8*-9*being novel biphenyls; compounds16*-19*being unusual8’,9’-dinoroxyneolignanes, compound14and20*being a7,9’:7’,9-diepoxylignane. Moreover, coumarins, stilbene, and lignans were isolated from S. baicalensis for the first time.The crude extracts of the roots of tested S. baicalensis and some isolated compounds were evaluated for their pharmacological effects according to the related literatures and their daily use.(1) The n-BuOH extract of S.baicalensis and compounds11and84showed significant osteoclast-inhibiting activities in vitro;(2) Twenty-nine compounds have been evaluated for acetylcholinesterase and butyrylcholinesterase inhibiting acitivites, but all of them have no significant activities;(3) Fifty-four compounds have been evaluated for anticancer activities, but all of them have no activities;(4) Sixty-one compounds are evaluated for their pharmacological effect by high-throughput screening and the result have not come out.The original determination of plant-derived subjects in the system of traditional herbal medicines is often complicated by the lack of morphological features in visual or microscopic inspection. Improved methods are urgently needed. In this paper, the profiles of proton nuclear magnetic resonance (1H NMR) and high performance liquid chromatography (HPLC) of fractionated non-polar and polar extracts from samples of Scutellaria baicalensis Georgi were recorded and analyzed by comparing them to each other and to those of the compounds of its own isolated in this work. The’H NMR spectra revealed not only the common features of chemical composition among collected samples of S. baicalensis, with the characteristic signals of their major constituents, flavonoids, being exhibited explicitly and reproducibly, but also the significantly signature features in the composition of signals when compared to other species. These features were further confirmed by HPLC and online HPLC/DAD/MS (mass spectrometry) analyses. Also, sixty-one flavonoids were isolated as pure monomers from the counterpart of the non-polar and polar extract of the roots of S. baicalensis. On the basis of chemical investigation, the signals and peaks in the profiles of1H NMR and HPLC were unambiguously assigned to their corresponding monomers. The general feature of1H NMR spectrum coupled with that of HPLC profile established for authentic sample explicitly provided the data of structures and composition for those particular compounds, which can be used as signature features for original authentication of S. baicalensis.Table1. Compounds isolated from Scutellaria baicalensis Georgi (*New compound)更多还原