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五味子联苯环辛烯类木脂素成分的结构与药理活性关系和药物创新 总被引:1,自引:0,他引:1
传统中药五味子具有多种药理活性。20世纪70年代以来,我国临床发现五味子能改善慢性肝炎病人的肝功能异常,在此基础上,我所化学家和药理学家对五味子分离得到的20余种联苯环辛烯类木酯素成分和其药理作用进行了大量研究。五味子的药理活性主要有:保肝,抗氧化,诱导肝药酶,增强解毒功能,促进蛋白质、糖原合成,克服肿瘤耐药性,增强对抗药癌的敏感性以及对中枢神经系统的镇静作用。在这些研究基础上,合成了保肝作用最强的五味子丙素结构类似物,相继研制出两种抗肝炎新药联苯双酯(DDB)和双环醇(bicyclol)。本文对五味子木脂素类成分的结构与药理活性关系以及两种新药的创制做一综述。 相似文献
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一种新型超临界流体萃取-高效液相色谱在线联用系统的构建 总被引:3,自引:0,他引:3
天然产物研究一直是植物学、化学和药学的重要研究领域.通过从天然产物中寻找生物活性成分和先导物是创制新药的有效途径之一.有效成分的提取是天然产物研究中最基本和最关键的环节.超临界流体萃取(Supercritical fluid extraction,简称SFE)是近年来发展较快的一种新型样品提取技术.超临界CO2作为最常用的萃取剂已被用于天然药物中非极性和弱极性有效成分的提取,尤其是挥发性和热敏性的物质.此外,通过加入适当的添加剂还可有效地萃取极性化合物,和传统的化学方法相比, 相似文献
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亚氨基糖由于具有重要的糖苷酶抑制活性、抗病毒和抗肿瘤活性等已经在新药创制中显示出巨大的发展潜力。系统研究此类化合物的构效关系有望发现高活性和高选择性的先导化合物。氟代是考察构效关系的常用方法之一。本文总结了氟代亚氨基糖的合成方法与化合物的糖苷酶抑制活性。合成方法中氟的来源包括含氟砌块、氟代糖或氟代试剂,三种合成策略各有优缺点与适用范围。基于氟代亚氨基糖的糖苷酶抑制活性研究,本文初步归纳了一些有代表性的重要亚氨基糖的构效关系,明确了糖环完整性对化合物糖苷酶抑制活性的重要意义。在此基础上对亚氨基糖的侧链或并环环系修饰则可能分别影响抑制谱和糖苷酶抑制活性。氟代亚氨基糖的研究成果是对亚氨基糖化学的重要贡献,以氟代为工具,必将进一步完善与修正亚氨基糖的构效关系,为设计合成具有潜在药物活性的亚氨基糖类化合物提供依据,并极大促进相关的新药创制工作。 相似文献
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农药是农业发展的保障,农业的发展离不开它。中国是农业大国,农药创制必须得依靠自己。中国农药的发展与中国农业现代化发展同频共振。新农药创制是一个系统工程,需要各个学科都能达到高科技水平。当今,中国的农药研究已经站在一个更高的起点和水平上,用自己原创的理论、方法、手段和靶标进行农药创制;一定程度上,中国的农药研究在某些领域已经开始引领全球农药发展。结合新中国成立后我国农药的发展状况,本文总结了70个自主创制农药产品。依据新创制农药的类型、创制时间、创制单位、主要作用对象、作用方式、作用机理等,概述了中国新创制农药的发展历程。 相似文献
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V. I. Bol'shakova L. I. Demenkova É. N. Shmidt V. A. Pentegova 《Chemistry of Natural Compounds》1989,24(6):691-694
The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 812–816, November–December, 1988. 相似文献
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利用手持技术改进测定乙醇分子结构实验 总被引:1,自引:0,他引:1
利用压强传感器代替排水集气法,改进测定乙醇分子结构实验的仪器装置,并探索最佳反应条件。另外,设计两个空白实验,结合压强变化曲线对实验误差进行相关讨论。 相似文献
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由于石化行业的生产需要,其材质的使用具有多样性和广泛性,经常会出现顾客委托的测试样品的一个或几个元素跨越光谱仪现有测试程序测量范围的情况。本法通过对光谱仪测试原理的认识,根据光谱仪的测试能力及标样的采集,实现了一个或几个元素测量范围的扩展,并对其测量的影响因素进行了研究。 相似文献
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Effect of the Method of Modification of Zeolite X on Selectivity of Catalytic Methylation of Toluene
Voloshyna Yu. G. Pertko O. P. Patrylak L. K. 《Theoretical and Experimental Chemistry》2019,54(6):395-400
Theoretical and Experimental Chemistry - The effect of the method of modification of catalysts based on zeolite X by cesium and magnesium cations (ion exchange and impregnation) on the selectivity... 相似文献
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Influence of viscosity of medium on processes of oxygen quenching of excited states of mesoporphyrin
E. I. Kapinus V. A. Ganzha B. M. Dzhagarov E. I. Sagun V. B. Pavlenko 《Theoretical and Experimental Chemistry》1989,25(2):146-151
The oxygen quenching rate constants for singlet and triplet excited states of the dimethyl ester of mesoporphyrin IX increase with decreasing viscosity of the medium and reach a maximum at a viscosity of approximately 0.4 mPa·sec, after which the rate constants begin to decrease. The drop in rate constant with increasing fluidity of the medium may be related to a nonequilibrium character of the elementary act in the interaction of the reactants in the solvent cage. In viscous media such as isopropyl alcohol, isobutyl alcohol, and isoamyl alcohol, the reaction radius is greater than the sum of the radii of the reacting particles. The long-range character of these processes is due to the relatively weak dependence of the quenching probability on distance.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 2, pp. 161–167, March–April, 1989. 相似文献
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The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted
indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator
model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was
established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing
analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997. 相似文献
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Kopranenkov V. N. Makarova E. A. Dashkevich S. N. Luk'yanets E. A. 《Chemistry of Heterocyclic Compounds》1982,18(11):1218-1218
Chemistry of Heterocyclic Compounds - 相似文献