254 resultados para 2-mercaptoimidazole modified silica gel


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本学位论文由4章组成。第一章是论文的主体,报道了中药射干的化学成分研究。第二章是中药射干代用品川射干的化学成分研究,并附带报道了西番莲化学成分的研究结果。第三章是射干、川射干及西番莲提取物化学成分串联质谱分析的报道。第四章为综述,概述了射干及鸢尾属植物的化学成分和药理研究进展。 在第一和二章中分别报道了射干(Belamcanda chinensis (L.) DC.)、川射干 (Iris tectorum Maxim.)及西番莲(Passiflora incarnate L.)化学成分的分离纯化与结构鉴定。采用正、反相硅胶柱层析、凝胶柱层析、薄层制备及HPLC等各种分离方法,从三种药用植物中共分离出68个不同的化合物,其中61个的结构得 得以鉴定,另外4个化合物的结构正在鉴定中,3个由于量少且有点杂质未作进一步的鉴定。 中药射干(Rhizoma Belamcandae)为射干植物的干燥根茎,从中共分离出53个化合物,通过红外、质谱及核磁共振等波谱方法鉴定了包括12个新化合物在内的48个,结构类型分别属于iridal型三萜及其新颖的二聚体、异黄酮、黄酮及黄酮醇、香豆素、甾体、芳香酸和脂肪酸及其甘油酯等。新化合物中有两个异黄酮类化合物,其结构分别鉴定为5,7,8,4′-四羟基-6-甲氧基异黄酮和5,6-二羟基-4′-甲氧基异黄酮-7-O-β-D-吡喃葡萄糖苷;八个新的iridal型三萜化合物分别鉴定为鸢尾烯(L)、16-甲氧基鸢尾烯、16-去羟基鸢尾烯、2-(E)-16-去羟基鸢尾烯、16-去羟基鸢尾烯B、3-乙酰基-16-去羟基鸢尾烯、iristectoroneL和iristectoroneM;两个结构骨架新颖的双三萜,分别命名为射干素A和射干素B,其分离纯化的困难以及结构的新颖和复杂突显出该论文的科学意义。除这些新化合物外,还有9个已知化合物为首次从中药射干中分离得到。此外,从中药射干的代用品川射干中分离得到7个已知化合物,主要是黄酮类成分及iridal型三萜化合物,其中1个三萜化合物为从射干中分离鉴定的新成分。另外还从西番莲中分离出8个化合物,鉴定了其中的6个,主要为黄酮碳苷。 第三章是关于射干、川射干及西番莲提取物化学成分的ESI-MS-MS分析,在初步探讨了从这些植物中分离鉴定出的一些异黄酮及黄酮碳苷的质谱裂解规律基础上,通过质谱和串联质谱分析,定性和半定量地检测了射干和川射干中主要的异黄酮成分以及西番莲中的黄酮碳苷成分,为这些药材品质的快速鉴定提供了一种简便方法。 第四章概述了射干及鸢尾属药用植物的化学和药理研究进展,特别是对其中异黄酮及三萜类成分的研究进展进行了深入系统的综述。 This dissertation is composed by four chapters. The first and second chapter reports the phytochemical investigation of three medicine plants, Belamcanda chinensis (L.)DC., Iris tectorum Maxim. and Passiflora incarnate L. Sixty eight different compounds were isolated and sixty one of them were identified. The third chapter described rapid ESI-MS-MS analysis of B. chinensis, I. tectorum, and P. incarnate. The forth part is a review about the progress of studies on the chemical constituents from Belamcanda chinensis and Iris species. Fifty-three compounds were isolated from Rhizoma Belamcandae, the rhizomes of B. chinensis by the methods of column chromatography (normal and reversed phase silica gel, Sephadex LH-20), preparative TLC and HPLC. On the basis of spectroscopic methods including IR, ESI-MS, 1-D and 2-D NMR, forty eight of them were identified as seventeen flavonoids, seventeen tritepenoids, one cumarin, five steroids and some benzene derivative etc. Among them, the structures of twelve new compounds were elucidated as 6-methoxy-5,7,8,4′-tetrahydryoxyisoflavoe, 4′-methoxy-5,6-dihydroxyisoflavone-7-O-β-D-glucopyranoside, iristectorene L, 16-methoxyisoiridogermanal, 16-dehydroxyisoiridogermanal, 2-(E)-16-dehydroxy isoiridogermanal, 16-dehydroxyiristectorene B, 3-acetyl-16-dehydroxyisoiridoger- manal, iristectorone L, iristectorone M, belamcandene A and belamcandene B. Last two new compounds are dimer of triterpenoids with a novel carbon skeleton. Beside the new compounds, nine known ones were isolated from this plant for the first time. Isolation of I. tectorum yielded seven compounds. On the basis of spectroscopic methods including ESI-MS, NMR and the comparison with authentic samples, three of them were determined as isoflavone, two of them were triterpenoids, and other two were β-sitosterol and apocynin. All of them are known compounds except one of iridal type triterpenoid, 16-dehydroxyiristectorene B, which also obtained from B. chinensis as a new compound. Isolation of P. incarnate yielded eight compounds. Six of them were determined on the basis of spectroscopic methods including ESI-MS, NMR and the comparison with authentic samples. Four of them are flavone-C-gluconside, and two are steroids. The third chapter describes the tandem mass spectrometry (ESI-MS-MS) analysis of the isoflavonoids from B. chinensis and I. tectorum, as well as C-glycosyl-flavonoide from P. incarnate, in order to explore the rapid methodology of validating the quality of the herbs. In addition, the fractionation rules of some iosflavonoids and C-glycosyl-flavonoids were discussed. The fourth chapter summarizes the research development on chemistry and pharmacology of medicine plants of B.chinensis and Iris species.

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本论文由三部分共4 章组成。第一部分阐述了大戟科大戟属传统中药千金子(Euphorbia lathyris L.)化学成分、生物学活性以及千金子化学成分的HPLC、UPLC-MS、GC-MS 分析成果。第二部分介绍了民族药材暖地大叶藓(Rhodobryum giganteum (Schwaegr.) Par.)的化学成分研究和结构鉴定。第三部分概述了大戟属 植物中大环二萜酯的研究进展。 第一章包括1-3 节。在第1, 2 节中报道了千金子(Euphorbia lathyris L.)95% 乙醇提取物的化学成分分离鉴定。我们采用正、反相硅胶柱层析、重结晶等各种分离方法,凭借MS、IR、NMR、X-ray 等现代仪器手段,从中共分离鉴定22 个化合物。其中8 个是高活性化合物前体-续随子烷型大环二萜及3 个巨大戟烷型二萜,还有香豆素、生物碱、甾体等类型,其中完成对5 个大环二萜酯构型的确认,对2 个二萜酯构型进行了修正。第3 节中介绍对千金子化学成分的细胞毒性、α-葡萄糖苷酶抑制活性、P-gp 表达抑制活性的模型筛选结果。 第二章包括3 节,第1 节报道不同产地千金子高效液相色谱定量分析结果。第2 节介绍了各大环二萜酯的HPLC-MS/MS 的分析结果,并且对其质谱裂解规律、UPLC-MS 快速鉴定方法做了进一步讨论。第3 节介绍了千金子挥发油成分分析。采用传统水蒸气蒸馏方法提取千金子中的挥发油,并经气相色谱-质谱联用(GC-MS)技术共分离鉴定出 49 个化合物,占挥发油总量的90.48%。 第三章包括1, 2 两节,第1 节报道了暖地大叶藓化学成分。采用正、反相硅胶,凝胶柱层析等各种分离方法和MS、IR、NMR 等解析手段,共分离鉴定10个化合物,其中一个环肽化合物为新化合物。第2 节介绍了暖地大叶藓挥发油成分分析,共分离鉴定出 52 个化合物,占其挥发油总量的85.67%。 第四章概述了大戟科大戟属植物中大环二萜酯的研究进展。 This dissertation consists of three parts. In the first part, it is elaborated that the phytochemical investigation from the traditional Chinese medicine: seeds of Euphorbia lathyris L.. Biological activity and constituents analysis by HPLC、UPLC-MS、GC-MS were reported. In the second part, it is discussed that the chemical constituents were isolated and identificated from minority nationalitical herb-Rhodobryum giganteum (Schwaegr.) Par.. The third part is a review about the progress of studies on macrocyclic diterpenes from Euphorbia. The first part is composed of 1-3 sections. The section 1and 2 is focused on the isolation and identification of chemical constituents from seeds of E. lathyris. 22 compounds were isolated from the seeds of E. lathyris. by isolation methods of column chromatography (silica gel, including reversed phase) and recrystallisation on the basis of spectroscopic methods including IR, MS, NMR and X-ray. In 8 macrocyclic and 3 ingenane diterpenes, the relative configuration of 5 macrocyclic diterpenes were confirmed, in which 2 were amended. In the third section, cell cytotoxic activity, restraining activity of α-Glucosidase and multidrug resistance (MDR) reversing activity about P-gp were tested. 5 potential revsering reagents were found. The second part is composed of 1-3 sections. In first section it is described that the quality of the chemical constituents of E. lathyris from 5 sources , which were analyzed by high-performance liquid chromatography. In addition, the fractionation rules of some macrocyclic diterpenes were discussed and Ultra Performance Liquid Chromatography/ electrospray ionization mass spectrometry (UPLC-MS) was applied for quick determination of compounds in the second section. In the third section, chemical analysis of the essential oil from seeds of E. lathyris by GC-MS were reported. The essential oil from the seeds of E. lathyris L. in Sichuan was extracted by steam distillation and 49 compounds were isolated and identified from the essential oil by gas chromatography-mass spectrometer (GC-MS). These compounds are accounted for 90.46% of the total essential oil. The second part, including section 4 and 5, is about the phytochemical investigation of R. giganteum. In the former section, ten compounds were isolated and identified. Among them, a new peptide was characterized by spectroscopic analysis including IR, MS and NMR. In the other section, 52 compounds were isolated and identified from the essential oil by gas chromatography-mass spectrometer (GC-MS). These compounds are accounted for 85.67% of the total essential oil. The third part is a review about the progress of studies on macrocyclic diterpenes from Euphorbia.

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本论文由三章组成。第一、二章分别报道钩藤、蹄叶橐吾的化学成分研究工作。从两种药用植物中共分离和鉴定了37 个化合物,其中有1 组6 个新的骨架相似的鞘糖脂类同系物及5 个新的倍半萜类化合物。第三章概述了艾里莫芬烷内酯类化合物的研究进展。 第一章报道钩藤(Uncaria rhynchophylla)带钩茎枝乙醇提取物的化学成分。采用正、反相硅胶柱层析等分离方法,运用NMR、MS 等波谱技术共分离鉴定得到22 个化合物,分属于五环三萜类化合物、鞘糖脂类化合物等,其中有1 组6个新的鞘糖脂类化合物同系物,另外有7 个化合物首次从该植物中分离得到。 第二章报道蹄叶橐吾(Ligularia fischeri)根部乙醇提取物化学成分的分离纯化和结构鉴定。通过正、反相硅胶柱层析等分离纯化和MS、NMR 等波谱解析,共分离鉴定得到18 个化合物,其中5 个是新化合物。它们的结构分别确定为3β-acetyl-6β, 8α, 10β-trihydroxyeremophila-7(11)-en-8, 12-olide (23), 3β-acetyl-8β,10β-dihydroxy-6β-(2-methylbutyryloxy)-eremophilenolide (24), 3β-acetyl-6β, 10β-dihydroxyeremophila-7(11), 8(9)-dien-8, 12-olide (25), 3β-acetyl-6β, 10β-dihydroxyeremophila- 7(11), 8(9)-dien-8, 12-olide (26), (3aR, 4R, 5S, 7aS)-2-acetyl-7ahydroxy-3a, 4, 5, 6, 7, 7a-hexahydro-1H-inden-5-yl acetate (27)。这5 个化合物经体外生物活性测试,结果表明化合物23 具有抑制酪氨酸磷酸酯酶的活性, 其IC50 值为1.30 μg/ml。 第三章概述了近二十年来艾里莫芬烷内酯类化合物的研究进展,包括其结构及药理活性两个方面,列举了从23 种植物中分到的114 个艾里莫芬烷内酯类化合物,同时也对其主要生物活性进行了总结。 This dissertation consists of three chapters. The first and second chapters elaborate the phytochemical investigation of Uncaria rhynchophylla and Ligularia fischeri. Thirty-seven compounds, including six new ones, were isolated and identified by spectroscopic methods and X-ray diffraction experiments. The third chapter is a review on the study progress of Eremophilanolides. The first chapter focus on the isolation and identification of chemical constituents from Uncaria rhynchophylla. Twenty-two compounds were isolated from the roots of U. rhynchophylla by repeat column chromatography over normal and reversed phase silica gel. Those compounds mainly belonged pentacyclic triterpenoids and sphingolipids. Among them, a series homologues of six sphingolipids were new compounds and seven compounds were firstly reported in this plant. The second chapter is about the phytochemical investigation of L. fischeri. Eighteen compounds were isolated and identified. Among them, four new erem-ophilanolides and a new dinoreremophilane derivative were characterized as 3β-acetyl-6β, 8α, 10β-trihydroxyeremophila-7(11)-en-8, 12-olide (23), 3β-acetyl-8β, 10β-dihydroxy-6β-(2-methylbutyryloxy)-eremophilenolide (24), 3β-acetyl-6β, 10β-dihydroxyeremophila-7(11), 8(9)-dien-8,12-olide (25), 3β-acetyl-6β, 10α-dihydroxyeremophila- 7(11), 8(9)-dien-8,12-olide (26), (3aR,4R,5S,7aS)-2-acetyl-7a-hydroxy-3a, 4, 5, 6,7, 7a-hexahydro-1H-inden-5-yl acetate (27) by spectroscopic analysis and confirmed by X-ray crystallography analysis. It was revealed that compound 23 has the ability to inhabit the PTP1B in vivo. And its IC50 is 1.30 μg/ml. The third part is a review on the study progress of Eremophilanolides.

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本论文由三章组成。第一章介绍了中药蜘蛛香的化学成分的研究成果,第二章为羧甲基魔芋葡苷聚糖-壳聚糖为细胞膜的天冬酰胺酶人工细胞的研究,第三章综述了人工细胞在生物医学领域的应用。 第一章报道了中药蜘蛛香(Valeriana wallichii)根部乙醇提取物的化学成分,采用正、反相硅胶层析等分离方法和MS、NMR等多种波谱手段,从中共分离鉴定出17个化合物,分别为缬草素(valtrate,1),valechlorine(2),homobadrinal(3),baldrinal(4),乙酰缬草素(acevaltrate 5),valeriotetrate C(6),valeriotetrate B(7),对羟基苯乙酮(4'-hydroxy-acetophenone 8),7-hydroxy valtrate(9),8-methylvalepotriate(10),1,5-dihydroxy-3,8-epoxyvalechlorine A(11),二氢缬草素(didrovaltrate 12),胡萝卜苷(13),橙皮苷 (hesperidin 14),prinsepiol-4-O-β-D-glucopyranoside(15),longiflorone(16),乙基糖苷(17)。其中化合物6、7、10、和11为新化合物,化合物9、15、16为首次从该植物中得到。新化合物11为含有氯原子的刚性骨架环烯醚萜,并且确定了其绝对构型。 第二章报道了以羧甲基魔芋葡苷聚糖(CKGM)和壳聚糖(CS)为膜的固定化L-天冬酰胺酶人工细胞研究成果。利用羧甲基魔芋葡苷聚糖和壳聚糖两种生物相容性很好的天然多糖之间的静电吸引力,在非常温和的条件下制备成具有半透过性膜的人工细胞,将治疗儿童急性成淋巴细胞性白血病(ALL)的药物L-天冬酰胺酶包裹在内。通过考察温度和pH对人工细胞的影响,结果表明以CKGM- CS为膜的L-天冬酰胺酶人工细胞对温度和pH的稳定性和耐受性均高于自由酶,说明CKGM-CS对酶具有保护作用,而且小分子底物和产物可以自由进出膜内外,而包裹在膜内的生物大分子则不能泄露出来。 第三章综述了微囊化人工细胞的研究进展。 This dissertation consists of three parts. In the first part, the chemical constituents from the root of Valeriana wallichii were reported. In the second part, preparation and characteristics of L-Asparaginase Artificial cell were reported. The third part is a review on progress of microcapsule artificial cell. The first chapter is about the isolation and identification of the chemical constituents from the root of V. wallichii. Seventeen compounds were isolated from the ethanol extract of roots of V. wallichii through repeated column chromatography on normal and reversed phase silica gel. By the spectroscopic and chemical evidence, their structures were elucidated as valtrate (1), valechlorine (2), homobadrinal (3), baldrinal (4), acevaltrate (5), valeriotetrate C (6), valeriotetrate B (7), 4'-hydroxy-acetophenone (8), 7-hydroxy valtrate (9), 8-methylvalepotriate (10), 1,5-dihydroxy-3,8-epoxyvalechlorine A (11), didrovaltrate (12), daucosterol (13), hesperidin (14), prinsepiol-4-O-β-D-glucopyranoside (15), longiflorone (16), and ethyl glucoside (17). Among them, 6, 7, 10, and 11 are new compounds. 15, 16 and 9 were isolated from this plant for the first time. The absolute configuration of compound 11, an unusual iridoid bearing a C-10 chlor-group and an oxo-bridge connecting C-3 and C-8 resulting in a rigid skeleton, was confirmed. The second chapter is about the semi-permeable microcapsule of carboxymethyl konjac glucomannan-chitosan for L-asparaginase immobilization. Carboxymethyl konjac glucomannan-chitosan (CKGM-CS) microcapsules, which have good biocompatibility, prepared under very mild conditions via polyelectrostatic complexation, were used for immobilize L-asparaginase-a kind of drug for acute lymphoblastic leukemia (ALL). The activity and stability under different temperature and pH of the enzyme loaded-microcapsules were studied. The results indicated the immobilized enzyme has better stability and activity contrasting to the native enzyme. The study illustrates that the L-asparaginase could be protected in CKGM-CS microcapsules, the substrate and product could pass through the system freely.

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本学位论文报道了西藏产三种藏族传统植物药材的化学成分研究。论文由四章组成,前三章是实验部分,分别报道了尼泊尔黄堇(Corydalis hendersonii Hemsl.)、藏波罗花(Incarvillea younghusbandii Sprague)和全缘叶绿绒蒿(Meconopsis interifolia Franch.)的化学成分研究结果。从这三种青藏高原药用植物中共分离鉴定出33 个化合物,其中1 个是新化合物。第四章概述了罂粟科紫堇属植物的化学和药理研究进展。 第一章为尼泊尔黄堇的化学成分研究。通过正、反相硅胶柱色谱等分离方法从药用植物尼泊尔黄堇的地上部分共分离纯化得到12 个化合物。运用MS、1H-NMR、13C-NMR、DEPT、HMBC、NOESY 等现代波谱学方法将它们的结构鉴定为:刺罂粟碱(1) , 普托品(2) , 新那亭(3) , 斯可任(4) , tetrahydrothalifendine (5) ,9-methyl-decumbenine C (6),tetrahydroberberrubine (7),隐品碱(8),α-别隐品碱(9),6,7-methylenedioxy-1(2H)-oxoisoquinolinone (10),6-丙酮基-5,6 -二氢血根碱(11)和β-谷甾醇(12)。其中化合物6 为新化合物,为首次发现的分子骨架上C-9 位连有甲基的苯肽异喹啉类型生物碱。另外,除化合物1 和2 外,其它9 个生物碱(3~11)均为首次从该种植物中分离得到。同时,我们还对对尼泊尔黄堇中的总生物碱进行了串联质谱分析。 第二章为藏波罗花的化学成分研究。从该药用植物的地上部分共分离得到16个化合物,通过理化常数和波谱数据鉴定为:异佛手柑内酯(1),6-甲氧基当归素(2),欧前胡素(3),花椒毒内酯(4),珊瑚菜素(5),水合氧化前胡素(6),rivulobirin A (7),齐墩果酸甲酯(8),咖啡酸甲酯(9),银桦酸(10),(D)-boschniakinic acid (11),对羟基苯甲酸(12) , tert-O-β-D-glucopyranosyl-(R)-heraclenol (13) , 5-methoxy-8-O-β-D-glucopyranosyloxypsoralen (14),前胡苷V(15)和苯乙醇-O-β-D-吡喃葡萄糖-(1→2)-O-β-D-吡喃葡萄糖苷(16)。所有以上化合物均为首次从该种植物中分离得到。另外我们还首次对藏波罗花挥发油的化学成分进行了气相色谱-质谱(GC-MS)联用分析,共鉴定出39 个挥发性成分。 第三章为全缘叶绿绒蒿化学成分的分离鉴定。从传统藏药材全缘叶绿绒蒿地上部分共分离纯化出8 个化合物。通过理化常数和波谱数据将他们的结构分别鉴定为:去甲血根碱(1),β-谷甾醇(2),3-羟基-齐墩果烷-12(13)-烯-30-酸(3),6-丙酮基-5,6-二氢血根碱(4),木犀草素(5),胡萝卜苷(6),quercetin 3-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranoside (7)和普托品(8)。其中化合物1,4 和7 为首次从该种药用植物中分离得到。 第四章为综述,总结和归纳了近年来罂粟科紫堇属植物的化学和药理研究进展。 This dissertation consists of four parts. The first, second and third parts report the studies on the chemical constituents from the medicinal plants of Corydalis hendersonii, Incarvillea younghusbandii and Meconopsis interifolia. The forth part reviews the progress of the studies on Corydalis species. The first chapter is about the isolations and identifications of alkalids from the aerial parts of C. hendersonii which is a traditional Tibetan medicine to treat febrifuge, high blood pressure and hepatitis. A new isoquinoline alkaloid, 9-methyl-decumbenine C (6), together with ten known alkaloids, stylopine (1), protopine (2), canadine (3), scoulerine (4), tetrahydrothalifendine (5), tetrahydroberberrubine (7), cryptopine (8), α-allocryptopine (9), 6,7-methylenedioxy-1(2H)-isoquinolinone (10) and 6-acetonyl-5,6-dihydrosanguinarine (11), and β-sitosterol (12) were isolated. Their structures were elucidated by spectroscopic methods. Furthermore, the total alkaloids were analyzed by ESI-MSn. The second chapter is about the isolations and identifications of chemical constituents from the aerial parts of I. younghusbandii. Sixteen compounds were isolated and purified by normal and reversed phase silica gel column chromatography. By spectral analysis, there structures were identified as isobergapten (1), sphondin (2), imperatorin (3), xanthotoxin (4), phellopterin (5), heraclenol (6), rivulobirin A (7), methyl oleanolate (8), methyl caffeate (9), grevillic acid (10), (D)-boschniakinic acid (11), 4-hydroxybenzoic acid (12), tert-O-β-D-glucopyranosyl-(R)-heraclenol (13), 5-methoxy-8-O-β-D-glucopyranosyloxypsoralen (14), decuroside Ⅴ(15), and phenylethyl-O-β-Dglucopyranosyl-(1→2)-β-D-glucopyranoside (16). All of these compounds were isolated from this plant for the first time.By the way, the chemical components of the essential oil from I. younghusbandii were analyzed by GC-MS for the first time. The third chapter is about the the isolations and identifications of the chemical constituents of M. interifolia. Eight compounds were isolated and identified as norsanguinarine (1), β-sitosterol (2), 3-hydroxyolean-12(13)-en-30-oic acid (3), 6-acetonyl-5,6-dihydrosanguinarine (4), luteolin (5), daucosterol (6), quercetin 3-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranoside (7) and protopine (8). The compounds 1, 4 and 7 were isolated from this herb for the first time. The last chapter is a review of the research progress of the studies on Corydalis species, which includes the chemical constituents in this genus and their pharmacology.

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本论文由三章组成。 第一章是关于厚朴中具有α-葡萄糖苷酶抑制活性成分的研究。凹叶厚朴的乙醇提取物显示了较强的α-葡萄糖苷酶抑制活性。为了确定其活性成分,在活性测试的指导下,通过溶剂萃取、树脂吸附和反复硅胶柱层析等分离方法从凹叶厚朴乙醇提取物中分离得到6 个生物碱,并用质谱和核磁共振等波谱方法分别鉴定为:木兰箭毒碱,木兰花碱,鹅掌楸碱,蕃荔枝碱,罗默碱和Lysicamine。应用小肠α-葡萄糖苷酶模型测定了它们对α-葡萄糖苷酶的抑制作用。其中,番荔枝碱和木兰箭毒碱对α-葡萄糖苷酶相对抑制活性最好,分别为60%和62%;其它四个生物碱成分对α-葡萄糖苷酶的抑制活性几乎相当,鹅掌楸碱为46%,罗默碱为51%,Lysicamine 为49%,木兰花碱为51%。 第二章报道了厚朴酚的衍生物及其对α-葡萄糖苷酶的抑制活性。根据糖苷酶抑制剂的结构特点,设计合成了一系列厚朴酚的衍生物。厚朴酚经过Mannich 反应和环氧化及开环反应制备了一系列衍生物,经活性测试发现衍生物活性与取代基关系较大,其中5,5′-diallyl-3-((bis(2-hydroxyethyl)amino)methyl)biphenyl-2,2′-diol 的抑制活性最高,为72%。 第三章综述了厚朴的化学成分及药理活性两个方面的研究进展。 The dissertation consists of three chapters. The first chapter is about the study on the constituents with α-glycosidase inhibitory activity from Magnolia officinalis. The EtOH extracts of M. officinalis Rehd. et Wils showed good inhibitory activity against α-Glucosidase. In order to determine the active compounds, bio-assay was used to guide the isolation. Six known alkaloids were isolated by solvent extraction and repeated silica gel column chromatography, and their structures were identified as liriodenine, anonaine, roemerine, lysicamine, magnoflorine and magnocurarine by spectroscopic methods. The inhibitory activity against α-Glucosidase of these alkaloids was measured with alvine screening model of α-glucosidase. Among them, lysicamine and liriodenine have the best inhibitory activity at 60% and 62%, respectively. The other four alkaloids have close inhibitory activity, from 46% to 51%. The second chapter is about the derivation of magnolol and the inhibitory a ctivity of the derivatives. Seven derivatives of magnolol were prepared by Manni-ch reaction, epoxidation followed by ring-opening reaction. Biological activity as say indicated the inhibitory activity was related to substituting groups. Among them, 5,5′-diallyl-3-((bis(2-hydroxyethyl)amino)methyl)biphenyl-2,2′-diol had the highest activity at 72%. The third chapter is a review on the progress of M. officinalis including chemical constituents and pharmacological activity.

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本学位论文主要研究一株放线菌发酵产物的抗肿瘤活性。先对该株放线菌进行活化培养,然后进行大批量发酵,发酵液经过冷冻离心,对离心得到的沉淀和上清液用不同极性的有机溶剂进行萃取,得到六个浸膏样品。对六个样品进行初步抗肿瘤活性检测。 然后对活性浸膏进行分离纯化和活性跟踪。本论文主要进行了如下的工作: 1、对菌种进行活化培养,利用该菌株在280C,200r.min-1条件下进行发酵实验,发酵时间为72h,发酵总量为15L。发酵液经过离心得到上清液和沉淀两部分。 2、分别用石油醚、乙酸乙酯、正丁醇萃取沉淀和上清液,得到编号为1—6的六个浸膏样品,对六个浸膏样品进行初步的细胞毒性和抗HepG2肿瘤活性实验,得出结论为5号样品活性最高。在没有分离纯化的情况下GI50达到0.76µg/mL。 3、对5号样品进行TLC实验,找出能够较好分离5号样品中各组分的溶剂组合,最后得出在氯仿:甲醇=8:1时分离效果较好。然后利用氯仿:甲醇=8:1的溶剂组合作为洗脱剂对5号样品进行过硅胶柱分离纯化并进行活性跟踪分离。 4、对分离纯化后得到的样品进行活性跟踪和结构分析。分离后得到样品A,在其浓度为10µg/ml时,抗肿瘤实验细胞的生长率为73.5%。在浓度为1.0mg/ml时,抗单纯疱疹病毒率(HSVⅡ)为74.5%。结构分析得知其分子式最可能为C41H43N8O4. This dissertation studied about the anti-tumor activity of an actinomycete fermentation product. First, we cultured the actinomycete. Second, we fermented it in large quantities, and then centrifuged the fermentation fluid; the next step is that we extract sedimentation and supernatant in different polar organic solvents, in turn to obtained six samples, which were detected about anti-tumor activity. Last, we purified active sample and tracked activity of it. We carried out the following research work: 1. Activation, culture and screening of the actinomyces was carried on. We used the screening strain to carry on the fermentation when the conditions are 280C,200r.min-1,the fermentation time is 72h. Fermentation fluid volume is 15L.And we obtained sedimentation and supernatant after fermentation fluid was centrifuged. 2. We used Petroleum ether, ethyl acetate, n-butanol separately to extract sedimentation and supernatant, and obtained six samples that were numbered 1-6. From the preliminary cell toxicity and the anti-tumor(HepG2) bioactivity experiment, we found that No.5 sample has the highest activity in the samples; the GI50 was 0.76µg/ml which has not been purified. 3. We Carried on TLC experiment on the No.5 sample, found the solvent composition that can separate each component of the No.5 sample. At last, we found that when the proportions are tri-chloromethane: methyl alcohol = 8:1, the Separation result was the best, and then we used the Solvent composition which proportion are tri-chloromethane: methyl alcohol = 8:1 as eluant to Purify No.5 sample by silica gel column. 4. We tracked the activity of pure sample obtained from Purification and analyzed structure of these substances. We got a compound A after separation, and the cell growth rate was 73.5% when its concentration was 10µg/ml. The anti-virus(HSVⅡ) rate was 74.5% when its concentration was 1.0mg/ml. We analyzed the Structure of A, and informed its molecular formula that was the most likely for C41H43N8O4.

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Heck coupling reactions of methyl acrylate with various aryl bromides have been investigated using a Pd/TPP catalyst in toluene under pressurized CO2 conditions up to 13 MPa. Although CO2 is not a reactant, the pressurization of the reaction liquid phase with CO2 has positive and negative impacts on the rate of Heck coupling depending on the structures of the substrates examined. In the case of either 2-bromoacetophenone or 2-bromocinnamate, the conversion has a maximum at a CO2 pressure of about 3 MPa; for the former, it is much larger by a factor of 3 compared with that under ambient pressure. For 2-bromobenzene, in contrast, the conversion is minimized at a similar CO2 pressure, being half compared with that at ambient pressure

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Heck coupling reactions of methyl acrylate with various aryl bromides have been investigated using a Pd/TPP catalyst in toluene under pressurized CO2 conditions up to 13 MPa. Although CO2 is not a reactant, the pressurization of the reaction liquid phase with CO2 has positive and negative impacts on the rate of Heck coupling depending on the structures of the substrates examined. In the case of either 2-bromoacetophenone or 2-bromocinnamate, the conversion has a maximum at a CO2 pressure of about 3 MPa;

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Two new silica-based organic-inorganic hybrid materials (B104SGs and O104SGs) doped with a binary mixture of imidazolium and phosphonium ionic liquids have been synthesized and used as sorbents in batch system for rare earths (RE) separation. Imidazolium ionic liquids 1-butyl-3-methylimidazolium hexafluorophosphate (C(4)mim(+)PF(6)(-)) or 1-octyl-3-methylimidazolium hexafluorophosphate (C(8)mim(+)PF(6)(-)) acted as porogens to prepare porous materials and additives to stabilize extractant within silica gel.

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Ce6-xDyxMoO15-delta (0.0 <= x <= 1.8) were synthesized by modified sol-gel method. Structural and electrical properties were investigated by means of X-ray diffraction (XRD), Raman, X-ray photoelectron spectroscopy (XPS) and electrochemical impedance spectroscopy (EIS). The XRD patterns showed that the materials were single phase with a cubic fluorite structure. Impedance spectroscopy measurement in the temperature range between 350 degrees C and 800 degrees C indicated a sharp increase in conductivity for the system containing small amount of Dy2O3. The Ce5.6Dy0.4MoO15-delta detected to be the best conducting phase with the highest conductivity (sigma(t) = 8.93 x 10(-3) S cm(-1)) is higher than that of Ce5.6Sm0.4MoO15-delta (sigma(t) = 2.93 x 10(-3) S cm(-1)) at 800 degrees C, and the corresponding activation energy of Ce5.6Dy0.4MoO15-delta (0.994 eV) is lower than that of Ce5.6Sm0.4MoO15-delta (1.002 eV).

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Solid solutions of Ce1-xNdxO2-x/2 (0.05 <= x <= 0.2) and (Ce1-xNdx)(0.95)MO0.05O2-delta (0.05 <= x <= 0.2) have been synthesized by a modified sol-gel method. Both materials have very low content of SiO2 (similar to 27 ppm). Their structures and ionic conductivities were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM) and electrochemical impedance spectroscopy (M). The XRD patterns indicate that these materials are single phases with a cubic fluorite structure. The powders calcined at 300 degrees C with a crystal size of 5.7 nm have good sinterability, and the relative density could reach above 96% after being sintered at 1450 degrees C. With the addition Of MoO3, the sintering temperature could be decreased to 1250 degrees C. Impedance spectroscopy measurement in the temperature range of 250-800 degrees C indicates that a sharp increase of conductivity is observed when a small amount of Nd2O3 is added into ceria, of which Ce0.85Nd0.15O1.925 (15NDC) shows the highest conductivity. With the addition of a small amount Of MoO3, the grain boundary conductivity of 15NDC at 600 degrees C increases from 2.56 S m(-1) to 5.62 S m(-1).

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Rare earth complex Eu(DBM)(3)phen (DBM: dibenzoylmethane, phen: 1.10-phenanthroline) hits been incorporated into unmodified MCM-41 and modified MCM-41s by aminopropyltriethoxysilane (APTES) or N-[(3-triethoxysilyl)propyl]ethylenediamine(TEPED). Thus, the assemblies of unmodified or modified MCM-41s with rare earth (RE) complex have been obtained. XRD spectra. NMR spectra. diffuse reflectance spectra. and the luminescence spectra were used to characterize the pure RE complex and the corresponding assemblies. The assemblies have better luminescence properties under UV irradiation. and their fluorescence lifetimes on the excited state are longer than that of the corresponding pure complex. The possible mechanisms are also discussed in the context.

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A novel amperometric biosensor utilizing two enzymes, glucose oxidase (GOD) and horseradish peroxidase (HRP), was developed for the cathodic detection of glucose. The glucose biosensor was constructed by electrochemical formation of a polypyrrole (PPy) membrane in the presence of GOD on the surface of a HRP-modified sol-gel derived-mediated ceramic carbon electrode. Ferrocenecarboxylic acid (FCA) was used as mediator to transfer electron between enzyme and electrode. In the hetero-bilayer configuration of electrode, all enzymes were well immobilized in electrode matrices and showed favorable enzymatic activities. The amperometric detection of glucose was carried out at +0.16 V (versus saturated calomel reference electrode (SCE)) in 0.1 M phosphate buffer solution (pH 6.9) with a linear response range between 8.0 x 10(-5) and 1.3 x 10(-3) M glucose. The biosensor showed a good suppression of interference in the amperometric detection.

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The electrocatalytic oxidation of methanol at the Titanium oxide (TiOx, x<2) film modified with Pt microparticles has been studied. The results show that the modified electrodes exhibit a significant electrocatalytic activity and good stability for the oxidation of methanol. Under the optimal conditions, the peak current density at 0.58 V for the oxidation of methanol in the positive-going sweep is about 526 mA/cm(2) at the scan rate of 5 mV/s in 0.5 mol/L CH3OH and 0.5 mol/L H2SO4 solution and the over potential of the methanol oxidation at the modified electrode increases about 30 similar to 40 mV after 70 minutes at the current density of 100 mA/cm(2) and 50 mA/cm(2). The enhanced electrocatalytic activity and good stability are ascribed to the high dispersion of Pt microparticles in and on the TiOx film and the synergistic effect between Pt microparticles and TiOx.