991 resultados para HYDROXY COMPOUNDS


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The (Ga,Mn,N) samples were grown by the implantation of low-energy Mn ions into GaN/Al2O3 substrate at different elevated substrate temperatures with mass-analyzed low-energy dual ion beam deposition system. Auger electron spectroscopy depth profile of samples grown at different substrate temperatures indicates that the Mn ions reach deeper in samples with higher substrate temperatures. Clear X-ray diffraction peak from (Ga,Mn)N is observed in samples grown at the higher substrate temperature. It indicates that under optimized substrate temperature and annealing conditions the solid solution (Ga,Mn)N phase in samples was formed with the same lattice structure as GaN and different lattice constant. (C) 2003 Elsevier Science B.V. All rights reserved.

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The (Ga,Mn,As) compounds were obtained by the implantation of Mn ions into semi-insulating GaAs substrate with mass-analyzed low energy dual ion beam deposition technique. Auger electron spectroscopy depth profile of a typical sample grown at the substrate temperature of 250degreesC showed that the Mn ions were successfully implanted into GaAs substrate with the implantation depth of 160 nm. X-ray diffraction was employed for the structural analyses of all samples. The experimental results were greatly affected by the substrate temperature. Ga5.2Mn was obtained in the sample grown at the substrate temperature of 250degreesC. Ga5.2Mn, Ga5Mn8 and Mn3Ga were obtained in the sample grown at the substrate temperature of 400degreesC. However, there is no new phase in the sample grown at the substrate temperature of 200degreesC. The sample grown at 400degreesC was annealed at 840degreesC. In this annealed sample Mn3Ga disappeared, Ga5Mn8 tended to disappear,Ga5.2Mn crystallized better and a new phase of Mn2As was generated. (C) 2002 Elsevier Science B,V. All rights reserved.

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A systematic study of syntheses and magnetic properties of the Nd-3 Fe29-xCrx (x=4.5, 4.7, 5.0, and 5.5) compounds has been performed. The single-phase compounds of Nd3Fe29-xCrx can be formed in the range 4.5 less than or equal to x less than or equal to 5.5. The Curie temperature Tc, the saturation magnetization M-S at 4.2 K, the anisotropy field H-A at 4.2 K and room temperature, and the intra-sublattice exchange coupling parameter j(FeFe) at 4.2 K for the Nd3Fe29-xCrx compounds decrease with increasing Cr composition from x=4.5 to 5.5, respectively. Nitrogenation and carbonation, unlike hydrogenation, result mainly in improvements of the Curie temperature, the saturation magnetization and the anisotropy field at 4.2 K and room temperature for the Nd3Fe29-xCrx compounds compared with their parent compounds.

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A pronounced photoluminescence enhancement on chemically oxidized porous silicon was induced by a series of organic cyano compounds including 1,2-dicyanoethylene (CE), 1,3-dicyanobenzene (1,3-CB), 1,4-dicyanobenzene (1,4-CB), 1-cyanonaphthalene (1-CN), and 9-cyanoanthracene (9-CA). Photoluminescence enhancement effects were reversible for all compounds studies in this work. A dependence of photoluminescence enhancement on the steric effect and the electronic characteristics of these compounds and the structure of the porous silicon substrates were analyzed in terms of the photoluminescence enhancing factors. Surface chemical composition examined by Fourier transform infrared (FTIR) spectra demonstrated that the surface Si-H bonds were not changed and no new luminescent compounds were formed on porous silicon surface during adsorption of cyano compounds. A mechanism based on induced surface states acting as radiative recombination centers by cyano compounds adsorption was suggested.

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Secondary metabolites produced by water-blooming cyanobacteria in eutrophic waters include some potent hepatotoxins, These compounds also have tumour-promoting properties, attributable to their inhibition and activation of protein phosphatases and kinases respectively. The inhibitory effect of these toxins on protein phosphatases have been employed in a commonly used radiometric assay, involving the use of a P-32-labeled substrate, for the detection and quantitation of these compounds. This paper investigates and describes a colorimetric method in which the activity of protein phosphatase 2A is determined by measuring the rate of colour production from the release of yellow p-nitrophenol using p-nitrophenyl phosphate as the substrate. Results of this study suggest that the colorimetric protein phosphatase inhibition assay is a simple, inexpensive tool for screening substances that may have tumour-promoting characteristics in aquatic systems. The detection limit of the colorimetric method is comparable to the radiometric assay. (C) 1998 Elsevier Science Ltd. All rights reserved.

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本论文由三章组成。第一章阐述了藏药水菖蒲的化学成分研究,共分离鉴定了39个化学成分,其中6个为新化合物。第二章报道了几种忍冬属植物的HPLC、HPLC-MS、GC分析以及抑菌活性、重金属含量测定结果。第三章概述了菖蒲属植物的研究进展。 第一章报道了水菖蒲(Acorus calamus L.)化学成分的分离纯化与结构鉴定。采用正、反相硅胶柱层析等分离方法,从水菖蒲的根中共分离出41个化合物,通过红外、质谱、核磁共振及X-ray单晶衍射等波谱方法和模拟计算方法鉴定了其中39个化合物的结构,主要为倍半萜、苯丙素、甾体类化合物。其中含有5个新的倍半萜类化合物和1系列新的甾体皂苷衍生物。经波谱分析将它们的结构鉴定为 1b, 7a(H)-cadinane-4a, 6a, 10a-triol (1), (2R,6R,7S,9S)-1(10), 4-cadinadiene-2, 9-diol (2), 1a, 5b-guaiane-10a-O-ethyl-4b, 6b-diol (7), 6b, 7b(H)-cadinane-1a, 4a, 10a-triol (13),(1R,4R,6S,10R)-1-hydroxy-7(11)-cadinen-5, 8-dione (14), 4′-O-正n碳酰基-3-O- β-D-葡萄糖基谷甾醇(n=14, 16, 18, 22) (15)。 第二章包括四个部分。第一部分报道了忍冬属三种植物40个样品的HPLC测定和对主要活性成分绿原酸的定量分析结果,以及运用HPLC-MS技术对色谱图中8个峰进行指认。在此基础上,考察了种植和采收多个因素对绿原酸含量的影响。第二部分报道了忍冬属三种植物27个样品的GC分析,根据样品的挥发性成分的保留时间对不同样品进行了定性比较,并考察了花期及海拔高度对植物挥发性成分的影响。第三、四部分分别阐述了灰毡毛忍冬和红腺忍冬的体外抑菌活性研究和重金属含量测定结果。 第三章全面系统地概述了菖蒲属植物的化学成分和药理活性研究进展。 This dissertation is composed by three chapters. The first chapter elaborates the phytochemical investigation of Acorus calamus L. Thirty-nine compounds including six new compounds were isolated and identified. The second chapter reports the research on genus Lonicera by HPLC, HPLC-MS and GC. Antifungal activity and heavy metals measurement of genus Lonicera were reported. The third chapter is a review about the research progress on the plant family of Acorus. The first chapter focuses on the isolation and identification of chemical constituents from Acorus calamus L.. Forty-one compounds were isolated from the root of Acorus calamus L. by repeat column chromatography over normal and reversed phase silica gel, the structure of thirty-nine compounds was identified by spectroscopic methods and computational methods, including IR, MS, NMR and X-ray. Those compounds mainly belonged to sesquiterpene, phenylpropanoid and steroid. Among them, five are new sesquiterpenes and one series are new steroid glycoside derivatives. Their structure were suggested as 1b, 7a(H)-cadinane-4a, 6a, 10a-triol (1), (2R,6R,7S,9S)-1(10), 4-cadinadiene-2, 9-diol (2), 1a, 5b-guaiane-10a-O-ethyl-4b, 6b- diol (7), 6b, 7b(H)-cadinane-1a, 4a, 10a-triol (13), (1R,4R,6S,10R)-1-hydroxy-7(11)- cadinen-5, 8-dione (14), 4′-O-carbonyl-3-O-β-D-glucosyl-sitosterol (carbonyl = tetradecanoyl, hexadecanoyl, octadecyl, docosanoyl) (15). The second chapter consists of four parts. The first part reports the HPLC analysis of forty samples of the genus Lonicera, and the quantitative investigation of chlorogenic acid in these samples by HPLC analysis. Relationship between the content of chlorogenic acid in different samples and their planting conditions and harvesting time were discussed. Furthermore, eight compounds were identified or tentatively characterized based on their mass spectra and UV spectra profiles. The second part is about qualitative analysis of the volatile constituent in twenty-seven samples of genus Lonicera by GC. The effect of planting altitude and harvesting time on the volatile constituent was also investigated. The third and fourth parts describe the antifungal activity and content of some kinds of heavy metals of L. macranthoides Hand.-Mazz. and L. hypoglauca Miq.. The third chaspter is a review about the research progress of the plant family of Acorus.

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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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首次从野桂花(Osmanthus yunnanensis Fr. P. S. Green)地上部分95%乙醇提取物中通过色谱分离得到20个化合物, 其中化合物20为新化合物。基于波谱数据它们被鉴定为(E)-阿魏酸二十烷基酯(1)、β-谷甾醇(2)、羽扇豆醇(3)、齐墩果酸(4)、7-oxo-β-sitosterol(5)、乙酰齐墩果酸(6)、(6′-O-palmitoyl)-sitosterol 3-O-β-D-glucoside(7)、rotundioic acid(8)、地榆糖甙Ⅱ(9)、27-O-(E)-对羟基肉桂酰-28-齐墩果酸(10)、27-O-(Z)-对羟基肉桂酰-28-齐墩果酸(11)、hycandinic acid ester(12)、绿原酸丁酯(13)、4,5-二咖啡酰奎尼酸丁酯(14)、4,5-dihydroxyprenyl caffeate(15)、28-O-β-D-glucopyranosyl rotundioic acid (16)、4-(6-O-caffeoyl-β-D-glucopyranosyloxy)-5-hydroxyprenyl caffeate (aohada-glycoside C, 17)、 4-β-D-glucopyranosyloxy-5-hydroxy-prenyl caffeate (aohada-glycoside A, 18)、β-胡萝卜甙(19)以及3-[O-β-D-(6-O-咖啡酰吡喃葡萄糖)]-甲基-2-烯-γ-内酯 (20)。化合物13、14、15和17有较强的α-葡萄糖甙酶抑制活性。当浓度为1 mg/ml时,它们对α-葡萄糖甙酶的抑制分别为61.5%、95.5%、72.1%、62.6%,活性高于阿卡波糖。 综述了木犀属植物化学成分及1993年以来苯丙素甙类化合物活性研究进展。 Twenty compounds were isolated from the 95% ethanol extract of the aerial parts of Osmanthus yunnanensis Fr. P. S. Green by chromatography for the first time. On the basis of spectral data, they were identified as (E)-ferulic acid eicosyl ester (1), β-sitosterol (2), lupenol (3), oleanolic acid (4), 7-oxo-β-sitosterol (5), acetyloleanolic acid (6), (6′-O-palmitoyl)-sitosterol 3-O-β-D-glucoside (7), rotundioic acid (8), ziyu glycosideⅡ (9), 3β-hydroxy-27-p-(E)-coumaroyloxy-olean-12-en-28-oic acid (10), 3β-hydroxy-27-p-(Z)-coumaroyloxyolean-12-en-28-oic acid (11), hycandinic acid ester (12), chlorogenic acid butyl ester (13), 4,5-di-O-caffeoylquinic acid butyl ester (14), 4,5-dihydroxyprenyl caffeate (15), 28-O-β-D-glucopyranosyl rotundioic acid (16), 4-(6-O-caffeoyl-β-D-glucopyranosyloxy)-5-hydroxyprenyl caffeate (aohada- glycoside C, 17), 4-β-D-glucopyranosyloxy-5-hydroxyprenyl caffeate (aohada- glycoside A, 18), β-daucosterol(19) and 3-[O-β-D-(6-O-caffeoylglucopyranosyl)]- methyl-2-en-γ-lactone (20). Compound 20 is a new one. Compounds 13, 14, 15 and 17 inhibit α-glucosidase with corresponding inhibitory rate of 61.5%, 95.5%, 72.1% and 62.6% at a concentration of 1 mg/ml, higher than acarbose. The chemical studies on Osmanthus genus and bioactivities of phenylpropanoid glycosides were summarized.