33 resultados para Methyl tetra-O-acetyl-d-glucopyranuronate

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本学位论文共有5章。第一章报道白芍的化学成分及芍药苷的微生物转化研究成果;第二章报道天山雪莲的化学成分研究;第三章报道两面针的化学成分研究;第四章报道通关藤的化学成分研究成果;第五章概述了花椒属植物中最近十年报道的新化合物及药理研究情况。 在第1章的第一部分报道了白芍(Paeonia lactiflora Pall.)的化学成分。我们采用正、反相硅胶柱层析等各种分离方法,从白芍的干燥根中共分离出14个化合物,其中1个为新化合物,其结构通过波谱分析证实为没食子酰白芍苷,另外还有2个为首次从该植物中分离得到。第二部分报道了芍药苷的微生物转化生产芍药苷代谢素-I的研究,从15株厌氧菌中筛选出10株有转化活性的菌株,其中短乳杆菌Lactobacillus brevis AS1.12的转化活性最好,对其转化条件进行了初步的筛选,确定了相对合理的转化工艺。 在第2章报道了天山雪莲(Saussurea involucrate Kar.et Kir.)全草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,共分离鉴定了28个化合物,结构类型分属于黄酮、倍半萜和木脂素等,其中2个新倍半萜化合物的结构分别表征为6α-羟基云木香酸6-β-D-吡喃葡萄糖苷和11βH-11,13-二氢去氢云木香内酯8α-O-(6′-乙酰)-β-D-吡喃葡萄糖苷。 第3章报道了两面针(Zanthoxylum nitidum (Roxb.)DC.)干燥根的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等波谱解析以及X-射线单晶衍射,共分离鉴定了16个生物碱,结构类型分属于苯并啡啶类、喹啉类和阿朴啡类等,其中2个新苯并啡啶类生物碱的结构分别表征为二聚双氢两面针碱和丙酮基双氢崖定椒碱。 第4章报道了通关藤(Marsdenia tenacissima (Roxb.) Wight et Arn.)水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等波谱解析以及X-射线单晶衍射,共分离鉴定了14个化合物,结构类型均属于C21多羟基甾醇,其中4个新化合物tenacigenoside A, tenacigenoside B, tenacigenoside C和tenacigenoside D的结构分别表征为3-O-6-deoxy-3-O-methyl-β-D-allopyranosyl-(1→4)-β-D-oleandropyranosyl-17β-tenacigenin B (62), 3-O-2,6- dideoxy-4-O-methyl-D-lyxo-hexopyranosly-11α-O- methylbutyryl-12β-O-acetyl-tenacigenin B (63), 3-O-6-deoxy-3-O-methyl-β-D- allopyranosyl-(1→4)-β-D-oleandropyranosyl-11α-O-tigloyl-tenacigenin C (64)和3-O-6-deoxy-3-O-methyl-β-D-allopyranosyl-(1→4)-β-D-oleandropyranosyl-11α-O-2- methylbutyryl-tenacigenin C (65)。 第5章概述了花椒属植物的化学成分及药理活性研究进展。 This dissertation consists of 5 chapters. The first chapter elaborate the phytochemical investigation of Paeonia lactiflora Pall., and microbial transformation of paeoniforin. The second, third and four chapters elaborate the phytochemical investigation of Saussurea involucrate Kar.et Kir., Zanthoxylum nitidum (Roxb.) DC. and Marsdenia tenacissima (Roxb.) Wight et Arn., respectively. Chapter 5 is a review on chemical constituents and bioactivities of Zanthoxylum species. The part one of chapter 1 focus on the isolation and identification of chemical constituents from P. lactiflora. Fourteen compounds were isolated from the roots of P. lactiflora by repeat column chromatography over normal and reversed phase silica gel. Among them, one is a new compound and the structure was suggested as galloyl-albiflorin by spectral evidence. In addition, two compounds were firstly reported in this plant. The part 2 is about microbial transformation of paeoniforin. Chapters 2, 3 and 4 were isolations and identifications of chemical constituents from S. involucrate, Z. nitidum and M. tenacissima, respectively. From the aerial parts of S. involucrate, 28 compounds including 7 flavonoids and 13 sesquiterpenoids were isolated and identified. Among them, 2 new compounds were characterized as 6α-hydroxycostic acid 6-β-D-glucoside and 11βH-11,13-dihydrodehydro- costuslactone 8α-O-(6'-acetyl)-β-D-glucoside, respectively, by means of spectroscopic analysis. Otherwise, 11 ones were firstly reported from this plant. The third chapter is about the phytochemical investigation of Z. nitidum. Sixteen compounds were isolated and identified. Among them, 2 new benzophenanthridine alkaloids were characterized as 8-acetonyldihydrofagaridine and 1,3-bis(8-dihydronitidinyl)-acetone by spectroscopic analysis. The fourth chapter is about the phytochemical investigation of M. tenacissima. Fourteen compounds were isolated and identified. Among them, 4 new compounds, tenacigenosides A~D, were characterized as 3-O-6-deoxy-3-O-methyl-β-D-allopyranosyl-(1→4)-β-D-oleandropyranosyl-17β- tenacigenin B, 3-O-2,6-dideoxy-4-O-methyl-D-lyxo-hexopyranosly-11α-O-methyl butyryl-12β-O-acetyl-tenacigenin B, 3-O-6-deoxy-3-O-methyl-β-D-allopyranosyl- (1→4)-β-D-oleandropyranosyl-11α-O-tigloyl-tenacigenin C, and 3-O-6-deoxy-3-O- methyl-β-D-allopyranosyl-(1→4)-β-D-oleandropyranosyl-11α-O-2-methylbutyryl- tenacigenin C. Chapter 5 is a review on recent progress in bioactive constituents from plants of Zanthoxylum species.

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A novel mimic TeHA was synthesized by modifying hyaluronic acid (HA) with tellurium, whose function is similar to that of glutathione peroxidase (GPX). The structure of TeHA was characterized by means of infrared spectroscopy and nuclear magnetic resonance spectroscopy, showing that the target Te is located at -CH2OH of the N-acetyl-D-glucosamine of HA. The activity of TeHA is 163.6 U/mu mol according to Wilson's method. In contrast to other mimics, TeHA displays a high activity. Moreover, TeHA can use many hydroperoxides as substrates, such as H2O2, cumenyl hydroperoxide, and tert-butyl hydroperoxide, and cumenyl hydroperoxide is the optimal substrate. A ping-pong mechanism was deduced for the reduction reactions catalyzed by TeHA according to the steady-state kinetic studies.

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A novel mimic was synthesized by modifying hyaluronic acid (HA) with tellurium, whose function is similar to that of glutathione peroxidase (GPX). The structure of TeHA was characterized by means of IR and NMR, the target-Te was located at -CH2OH of the N-acetyl-D-glucosamine of HA. The H2O2 reducing activity of TeHA, by glutathione (GSH), was 163.6 U/mu mol according to Wilson's method. In contrast to other mimics, TeHA displayed the highest activity. Moreover, TeHA accepted many hydroperoxides as its substrates, such as H2O2, cumenyl hydroperoxide (CuOOH) and tert-butyl hydroperoxide (t-BuOOH), and CuOOH was the optimal substrate of TeHA. A ping-pong mechanism was observed in the steady-state kinetic studies of the reactions catalyzed by TeHA.

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Behavioral stress facilitates long-term depression but impairs long-term potentiation in the hippocampus. Recent evidence in vitro demonstrates that the NIR2B-containing N-methyl-D-aspartate subtype glutamate receptor antagonist Ro25-6981 prevents the beh

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Long term potentiation in hippocampus, evoked by high-frequency stimulation, is mediated by two major glutamate receptor subtypes, alpha-amino-3-hydroxyl-5-methyl-4-isoxazole propionate receptors and N-methyl-D-aspartate receptors. Receptor subunit compos

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Efficient synthetic procedures for the preparation of beta-trithiophenes (dithieno[2,3-b:3',2'-d]thiophene) and two macrocyclic compounds, tetra[2,3-thienylene] and hexa[2,3-thienylene] bearing trimethylsilyl (TMS) groups from 2,2'-dibromo-5,5'-bistrimethylsilanyl[3,3']bithiophenyl are reported. The UV-Vis spectra property and crystal structures of these macrocyclic oligothiophenes are described.

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The thermooxidative degradtion of ethylene oxide and tetra-hydrofuran (EO-THF) co-polyether has been studied by electron spin resonance (ESR), Fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR) spectroscopy. The initial degradation site was found to be at the a-carbon of the ether bond. Two free radicals which derived from dehydrogenation and oxygen addition were successfully detected by spin-trapping technique which used alpha -phenyl-N-tert-butyl nitrone(PBN) as spin trap. Both FT-IR and NMR have been used to follow structural changes of the copolyether during degradation. Nearly 20 product fragments including formate, carbonate, methyl, alcohol, methylene-dioxy, hydroperoxide and semiformal have been characterized by D-1 and D-2 NMR. The thermooxidtion of co-polyether preferred to occur on the THF units especially at the alternating linkage of EO and THF. Antioxidant (BHT) not only retarded the thermooxidation but also modified the degradation products with less ester and methylene-dioxy groups hut more hydroxyl and methyl groups.

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D-Serine, the endogenous coagonist of N-methyl-D-aspartate receptors (NMDARs), is considered to be an important gliotransmitter, and is essential for the induction of long-term potentiation. However, less is known about the role of D-serine in another for

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Extracellular polymeric substances (EPS) from four filamentous cyanobacteria Microcoleus vaginatus, Scytonema javanicum, Phormidium tenue and Nostoc sp. and a coccoid single-cell green alga Desmococcus olivaceus that had been separated from desert algal crusts of Tegger desert of China, were investigated for their chemical composition, structure,and physical properties. The EPS contained 7.5-50.3% protein (in polymers ranging from 14 to more than 200 kD, SDS-PAGE) and 16.2-46.5% carbohydrate (110-460 kD, GFC). 6-12 kinds of monosaccharides, including 2-O-methyl rhamnose, 2-O-methyl glucose, and N-acetyl glucosamine were found. The main carbohydrate chains from M. vaginatus and S. javanicum consisted mainly of equal proportion of Man, Gal and Glc, that from P. tenue consisted mainly of arabinose, glucose and rhamnose. Arabinose was present in pyranose form, mainly alpha-L 1 --> 3 linked, with branches on C4 of almost half of the units. Glucose was responsible for the terminal units, in addition of having some units as beta1 --> 3 and some as beta1 --> 4 linked. Rhamnose was mainly 1 --> 3 linked with branches on C2 on half of the units. The carbohydrate polymer from D. olivaceus was composed mainly of beta1 --> 4 linked xylose, galactose and glucose. The galactose part was present both in beta-pyranose and -furanose forms. Arabinose in alpha-L-furanose form was mainly present as 1 --> 2 and 1 --> 2, 5 linked units, rhamnose only as alpha 1 --> 3 and xylose as beta 1 --> 4. The backbone of the polysaccharide from Nostoc sp. was composed of beta-1 --> 4 linked xylose, galactose and glucose. Most of the glucose was branched on position C6, terminal glucose and 2-O-methyl glucose units are also present. The relationship between structure, physical properties and potential biological function is discussed. (C) 2003 Elsevier Ltd. All rights reserved.

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本论文对四川蜡瓣花 (Corylopsis willmottiae Rehd. et Wils.)、密花樫木[Dysoxylum densiflorum (Blume) Miq.]、四川溲疏 (Deutzia setchuenensis Franch)及云南豆腐柴 (Premna yunnanensis W. W. Smith)的化学成分进行了研究。通过色谱分离得到44个化合物。主要基于波谱数据鉴定了它们的结构,其中1个为新化合物。 1.从四川蜡瓣花全株的95%乙醇提取物中共分离鉴定了13个化合物,它们是:1-O-(3-O-甲基没食子酸)-岩白菜素(1)、11-O-没食子酰基岩白菜素(2)、 11-O-紫丁香基岩白菜素(3) 、岩白菜素(4)、4-O-没食子酰基岩白菜素(5) 、4,11-O-二没食子酰基岩白菜素 (6)[14]、β-谷甾醇 (7)、acetyl aleuritolic acid (8)、(-)-表没食子儿茶素没食子酸酯(9)、对羟基苯甲酮 (10)、 11-香豆酸酰岩白菜素 (11)[19]、丁香酸 (12)和没食子酸 (13)。其中1为新化合物。 2.从密花樫木根的95%乙醇提取物中共分离纯化了13个化合物,它们是:β-白檀酮(14)、richenone (15)、β-谷甾醇 (7)、cabraleadiol (16)、β-香树脂醇 (17)、龙脑香醇酮 (18)、cabraleadiol monoacetate (19)、cabraleone (20)、3β-hydroxy-5 -pregnen-20-one (21)、3β-hydroxy-5α-pregnan-20-one (22)、cabraleahydroxylactone (23)、川楝子甾醇B (24)、表儿茶素 (25)。 3.从四川溲疏全株95%乙醇提取物中共分离11个化合物,鉴定了其中的9个化合物。它们是:β-谷甾醇 (7)、白桦酯醇(26)、齐墩果酸(27)、hydrangetin (28)、肉桂酸 (29),齐墩果酸-3-O-β-D-吡喃葡萄糖醛酸苷(30)、β-胡萝卜苷 (31)、齐墩果酸-3-O-(β-D-吡喃葡萄糖醛酸-6-正丁酯)(32)、齐墩果酸-3-O-β-D-吡喃葡萄糖醛酸-28-O-β-D-吡喃葡萄糖苷 (33)。 4.从云南豆腐柴95%乙醇提取物中分离得到12个化合物,分别为白桦脂醇 (25)、7-羟基黄烷酮 (34)、松属素 (35)、2’,4’-羟基查儿酮 (36)、高良姜素-3-甲醚 (37) 、高良姜素-3,7-二甲醚 (38)、异甘草素-4-甲醚 (39)、豆蔻明 (40)、乔松酮 (41)、异甘草素 (42)、arjunolic acid (43)、槲皮素3-O-β-D-木糖苷(44)。 5.综述了1976年以来樫木属植物化学成分和活性研究的概况。 Phytochemical investigation on Corylopsis willmottiae, Dysoxylum densiflorum, Deutzia setchuenensis, and Premna yunnanensis, led to the isolation of 44 compounds, 1 of which was new one. 1. One new compound was isolated from 95% ehanolic extrat of the whole plants of C. willmottiae, identified as 11-O-(3-O-methylgalloyl)-bergenin (1). The twelve known compounds isolated were 11-O-galloylbergenin (2), 11-O-syringylbergenin (3), bergenin (4), 4-O-galloylbergenin (5), 4,11-di-O-galloylbergenin (6), β-sitosterol (7), acetyl aleuritolic acid (8), (-)-epigallocatechin 3-O-gallate (9), 1-(4-hydroxyphenyl) ethanone (10), 11-O-coumaroylbergenin (11), syringic acid (12), gallic acid (13). 2. Thirteen compounds were isolated from 95% ethanol extract from the roots of D. densiflorum and identified as β-amyrenone (14), richenone (15), β-sitosterol (7), cabraleadiol (16), β-amyrin (17), hydroxydammarenone-Ⅱ (18), cabraleadiol monoacetate (19), cabraleone (20), 3β-hydroxy-5-pregnen-20-one (21), 3β-hydroxy-5α-pregnan-20-one (22), cabraleahydroxylactone (23), toosendansterol B (24) and (-)-epicatechin (25). 3. Eleven compounds were isolated from ethanol extract of D. Setchuenensis. Nine were identified as β-sitosterol (7), betulin (26), oleanolic acid (27), hydrangetin (28), cinnamic acid (29), oleanolic acid 3-O-β-D-glucuronopyranoside (30), β-daucosterol (31), oleanolic acid 3-O-β-D-glucuronopyranoside-6-O-butyl ester)(32), oleanolic acid 3-O-β-D-glucuronopyranosyl-28-3-O-β-D-glucopyranoside (33). 4. Twelve compounds were isolated from ethanol extract of P. yunnanensis and identified as betulin (26), 7-hydroxyflavanone (34), pinocembrin (35), 2’,4’-dihydroxychalcone (36), galangin 3-methyl ether (37), galangin 3,7-dimethyl ether (38), isoliquiritigenin 4-methyl ether (39), cardamonin (40), pinostrobin (41), isoliquiritigenin (42), arjunolic acid (43), quercetin 3-O-β-D-lyxosopyranoside (44). 5. Chemical constituents and biological activities of the genus Dysoxylum (Meliaceae) were reviewed during 1976-2009.

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本论文由三部分共四章组成。第一部分介绍丁香化学成分的研究成果,第二部分为升麻的化学成分研究,第三部分综述了环菠萝蜜烷三萜结构和活性关系的研究现状。 第一部分包括第一和第二章。第一章介绍了丁香(Eugenia caryophyllataThunb.)花蕾的化学成分和结构鉴定。采用正、反相硅胶柱层析等各种分离方法,从其乙醇提取物的乙酸乙酯萃取物和正丁醇萃取物中共分离出34 个化合物,它们的结构类型分属黄酮、三萜、鞣质等。其中1 个为新的酚苷类化合物,其结构经波谱分析鉴定为2-O-(6'-O-没食子酰基)-b-D-葡萄糖基苯甲酸甲酯(24),另外还有12 个化合物为首次从该植物中分离得到。第二章介绍了丁香挥发油的气相色谱- 质谱联用( GC-MS )和正丁醇萃取物的高效液相色谱- 质谱联用(HPLC-MS/MS)分析,尝试简单快速地检测丁香挥发油及极性部分的主要化学成分的方法。 第二部分为第三章。本章介绍了传统中药升麻(Cimicifuga foetida L.)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方法和MS、NMR 等波谱解析技术,共分离鉴定了20 个化合物,主要为环菠萝蜜烷三萜,其中5 个新三萜化合物分别鉴定为cimicidol-3-one(38)、3'-O-乙酰基升麻苷H-1(41)、2'-O-乙酰基升麻苷H-1(42)、(3b,12b,16b)-12-乙酰氧-16,23-环氧-9,19-环羊毛甾烷-22-烯-24-酮3-O-b-D-吡喃木糖苷(44)和升麻碱(54)。新化合物54 为结构新颖的环菠萝蜜烷三萜皂苷生物碱,这是首个发现的具有环菠萝蜜烷三萜骨架的生物碱,也是从升麻属植物中发现的第一个三萜生物碱,它的结构通过多种波谱解析,特别是2D-NMR 的充分应用,并结合化学降解和反应得到证实。此外,还介绍了分离得到的一种具有明显抑制破骨细胞活性的化合物(QS29)的体外活性研究。 第三部分即第四章,综述了升麻属植物中环菠萝蜜烷三萜与其生物活性的构效关系研究现状。 This dissertation consists of three parts. In the first and the second parts, thechemical constituents from the flower buds of Eugenia caryophyllata and therhizomes of Cimicifuga foetida were reported. The third part is a review on astructure-activity relationship of the cycloartane triterpenoid from Cimicifuga species. The first part is composed of two chapters. The chapter 1 is about the isolationand identification of the chemical constituents from the flower buds of E.caryophyllata. A new phenolic glucoside gallate, methyl 2-O-(6’-O-galloyl)-b-D-glucopyranosylbenzoate (24), together with thirty-three known compounds has beenisolated from the ethanol extract of the flower buds of E. caryophyllata throughrepeated column chromatography on normal and reversed phase silica gel. Thestructure of the new compound was elucidated on the basis of spectral and chemicalevidence. Those kno wn compounds were belonged to flavone, triterpenoid, tannin andsome simple compounds. Among them, 12 compounds were isolated from the titleplant for the first time. The second chapter describes the capillary GC-MS analysis ofthe volatile components and the HPLC-MS/MS analysis of the polar constituents fromthe flower buds of E. caryophyllata, in order to detect the main constituents in thecrude extract rapidly and precisely. The third chapter is about the chemical constituents of the rhizomes C. foetida, atraditional Chinese medicine which was used as anti-inflammatory, analgesic andantipyretic agents. Our investigation of the bioactivities constituents of the rhizomesof C. foetida led to the isolation of five new cycloartane triterpenoids, which werecharacterized as cimicidol-3-one (38), 3'-O-acetyl cimicifugoside H-1 (41),2'-O-acetyl cimicifugoside H-1 (42), (3b,12b,16b)-12-acetoxy-16,23-epoxy-9,19-cyclolanost-22-ene-24-one 3-O-b-D-xylopyranoside (44) and cimicifugadine (54),along with fifteen known compounds through repeated column chromatography onnormal and reversed phase silica gel. Among them, 54 is a novel cycloartanealkaloid and first discovered as a new type alkaoid from nature. The structures ofthese compounds were elucidated on the basis of spectral and chemical evidence, andcimicidol-3-one was confirmed by X-ray crystallography analysis. Moreover, onecompound exhibited strong anti-osteoporosis activity in vitro experiment. The fourth part is a review on a structure-activity relationship analysis of thecycloartane triterpenoid from Cimicifuga species.