中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
帚状香茶菜二萜化学成分及杂二萜scopariusicide G的合成

文献类型:学位论文

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作者蒋学春
答辩日期2021-11
导师孙汉董
英文摘要The dissertation is comprised of four chapters. Reported in chapter one was the phytochemical investigation of the aerial parts of Isodon scoparius (C. Y. Wu et H.W. Li) H. Hara (Labiatea), resulting in the discovery of several bicyclic diterpenoids. And the absolute configurations of these compounds were determined by derivatization, quantum chemical calculation and single crystal X-ray diffraction analysis. New compounds were screened for their antibacterial activities and fluconazole resistant reversal activities against Candida albicans. In the second chapter, it focused on the synthesis of the rare compounds, scoparodanes A and B from I. scoparius; The third chapter described the synthetic study of scopariusicide G, a novel ent-clerodane-derived meroditerpenoid with a unique cyclobutane ring. In the last chapter, it reviewed the synthetic progress on the construction of cyclobutane motifs and its applications in the synthesis of complex natural products. I. scoparius is a morphologically specific one of Isodon species. On the basis of our previous research, we conducted further investigation on the chemical constituents of the part of chloroform: acetone (1:1) of I. scoparius, and discovered the antibacterial activities and fluconazole resistant reversal activities of ent-clerodanoids. Although a large number of new bicyclic diterpenoids were isolated from this species, the oxigened-C11 or C12 on the flexible side chains ring have brought great challenges to their absolute configuration determination. We finally verified the structures of these new compounds by a combination of synthetic methods staring from the know compounds and single crystal X-ray diffraction analysis or quantum chemical calculation of the precursors or intermediates. The biomimetic synthesis of 3,4-seco-ent-clerodanoids not only verified the absolute structures of these compounds but also mimicked the biogenetic hypothesis, which offered meaningful reference for further research. Moreover, the advantages of low toxicity, facile synthesis, and excellent resistant reversal activity facilitate the discovery of potential lead compounds. The structures of ent-clerodanoids feature flexible side chains and continuous chiral centers in ring-B, which pose a great challenge to enantioselective synthesis. This dissertation reported the first intramolecular iron Diels-Alder reaction applied to construct the bicyclic skeleton of ent-clerodanoids in scopariusicide G, and synthetic model study to access the right chiral spiro [3.5] structures by the key [2+2] cycloaddition reaction. Although it has a long way to access the target molecular, scopariusicide G, the construction of the core skeleton has been achieved. These results provided credible support for the total synthesis of scopariusicide G. Chapter 1. Chemical and Biological Studies of Bicyclic Diterpenoids from I. scoparius Figure 1 Structure elucidation of ent-clerodanoids Six bicyclic diterpenoids, including three new comp
源URL[http://ir.kib.ac.cn/handle/151853/74641]  
专题昆明植物研究所_昆明植物所硕博研究生毕业学位论文
推荐引用方式
GB/T 7714
蒋学春. 帚状香茶菜二萜化学成分及杂二萜scopariusicide G的合成, Chemical Research on Diterpenoids and Synthesis Study of Meroditerpenoid, Scopariusicide G, from I. scoparius[D]. 2021.

入库方式: OAI收割

来源:昆明植物研究所

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