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1.
目的对药用植物云南龙胆的化学成分进行研究。方法采用硅胶、Sephadex LH-20、ODS和MCI等多种柱层析方法进行分离纯化,采用现代波谱学技术对分离得到的化合物进行结构鉴定。结果从云南龙胆全株的正丁醇部位分离得到6个木脂素苷类成分,分别鉴定为:4,4′-Dimethoxy-3′-hydroxy-7,9′:7′,9-diepoxylignan-3-O-β-D-glucopyranoside(1)、Syringaresinol-4′-O-β-D-glucopyranoside(2)、Dehydrodiconiferyl alcohol-4-O-β-Dglucopyranoside(3)、(7S,8R)-Balanophonin-4-O-β-D-glucopyranoside(4)、(7S,8R)-Dehydrodiconiferyl alcohol-9′-O-β-D-glucopyranoside(5)、Lariciresinol-4-O-β-D-glucopyranoside(6)。结论该6个木脂素苷类成分均首次从该药用植物中分离得到。  相似文献   

2.
用过氧化物分解法合成得到了[Co(aipamp)(amp)Cl][ZnCl4](aipamp=2-[(2-氨异丙基)氨基甲基]呲啶,amp=2-(氨甲基)吡啶)配合物,晶体学参数:三斜晶系,空间群Pi,a=0.995 7(2),b=1.020 7(3),C=1.147 8(3)nm,α=102,584(5)°,β=91.559(5)°,γ=98.462(5)°,V=1.124 0(5)nm3,Dc=1.699 g·cm-3,Z=2,F000=580,R=0.044 9,ωR=0.098 4;晶胞中含2个配合物阳离子,2个[ZnCl4]2-阴离子;异构体中co3 为六配位,且配合物阳离子中具有C—H…π结构.  相似文献   

3.
利用硅胶柱色谱、Sephadex LH-20等色谱法从鞭打绣球的95%乙醇提取物的乙酸乙酯部分中分离得到10个化合物.根据化合物的理化性质和~1H NMR、~(13)C NMR鉴定化合物为齐墩果酸(1),β-谷甾醇(2),紫丁香苷(3),苯基β-D-吡喃葡萄糖苷(4),苄基β-D-吡喃葡萄糖苷(5),熊果苷(6),草夹竹桃苷(7),反式肉桂酸(8),顺式肉桂酸(9),丁香醛(10).其中化合物3~7和10为首次从该植物中获得.通过体外α-葡萄糖苷酶抑制模型对以上化合物进行活性筛选,结果显示化合物1和10对α-葡萄糖苷酶活性具有一定的抑制作用, IC_(50)值分别为(68.93±6.20)μmol/L、(71.77±6.46)μmol/L.  相似文献   

4.
采用快速液相-三重串联四极杆质谱(RRLC-ESI-MS/MS)技术,在电喷雾质谱正模式和负模式下,对红珠胶囊内容物进行分析鉴定。通过质谱中分子离子峰和碎片离子峰的精确相对分子质量匹配,保留时间,紫外光谱对比,与对照品比对并结合参考文献鉴定,确证和指认了红珠胶囊中的新北美圣草苷、樱桃苷、柚皮苷、忍冬苷、野漆树苷、橙皮内酯水合物、7-(2″-α-鼠李糖基-6″-(3″″-羟基-3″″-甲基戊二酰)-β-D-葡萄糖基)柚皮素、异橙皮内酯、柚皮素9个化学成分。研究揭示了红珠胶囊的化学物质基础,为控制该药质量提供了依据。  相似文献   

5.
用循环伏安法研究了两个新的三元配合物[Ni(phendio)(TPA)](CIO_4)_2(1)和[Cu(phendio)(TPA)] (CIO_4)_2(2)(phendio=1,10-菲咯啉-5,6-二酮,TPA=三(2-吡啶甲基)胺)在pH 2~9的磷酸盐缓冲溶液中的电化学性质.实验结果表明,在-0.3~0.4 V(vs.SCE)电位扫描范围内这两个配合物都表现出与pH值相关的氧化还原活性,pH<4时,是2e~-/3H~ 过程,pH>4时为2e~-/2H~ 过程.  相似文献   

6.
麻花秦艽化学成分的研究   总被引:4,自引:1,他引:3  
通过硅胶柱层析及薄层层析方法对甘肃产麻花秦艽(Gentiana straminea Maxim)根醇提物进行分离,得到7个化合物,应用核磁共振等光谱方法及与对照品对照鉴定结构分别为龙胆苦苷(gentiopicroside,Ⅰ),熊果酸(ursolic acid,Ⅱ),胡萝卜苷(β-sitoseteryl-3-O-β-D-glucopyranoside, Ⅲ),β-D-葡萄糖乙苷(ethyl-β-D-glucopyranoside, Ⅳ),N-正二十五烷-2-羧基苯甲酰胺(N-pentacosy-2-carboxy-benzoylamide,Ⅴ),乌苏醇(uvaol,Ⅵ)和2'-(邻,间-二羟苯甲酰)獐牙菜苷(2'-(o,m-phenylglycin)sweroside,Ⅶ)。其中化合物Ⅳ为从该属中首次分离得到的化合物,化合物Ⅴ,Ⅵ和Ⅶ为该植物中分离得到的化合物。  相似文献   

7.
从中国南海海域采集的乌绿草虫软珊瑚Cespitularia cocerulea May中分离到3个化合物。经波谱分析,确定它们的化学结构为:(2S,3R,2 R,4E,8E)-N-(2-羟基-正二十碳酰基)-9-甲基-4,8-二烯-1,3-二羟基-2-氨基-十九烷(1),Δ4,5(E),Δ8,9(E)-鞘胺醇-正十六碳酰胺(2)和麦角甾-3β,5α,6β-三醇(3),其中1为新化合物。  相似文献   

8.
新疆产黄花蒿挥发油成分研究   总被引:9,自引:0,他引:9  
采用水蒸汽蒸馏法提取,运用毛细管气相色谱.质谱联用法对新疆产黄花蒿(Artemisia annua L.)挥发性化学成分进行了分析,用气相色谱面积归一化法测定了各成分的相对百分含量,经毛细管色谱分离出48个峰,并鉴定出峰所对应的化合物,其主要化学成分为2,5-二氢-3-甲基呋喃(68.48%);β—月桂烯(10.13%);1R,3Z,9S-4,11,11-三甲基-8-亚甲基二环[7,2,0]-3-十一碳烯(7.74%);7,11-二甲基-3-亚甲基-1,6,10-十二碳三烯(2.42%);桉油醇(1.68%);圣亚麻三烯(1.52%)等,为进一步开发利用提供了科学依据。  相似文献   

9.
采用MCI柱色谱、硅胶柱色谱、Sephadex LH-20凝胶柱色谱和半制备HPLC等色谱分离手段对半育耳蕨的化学成分进行研究.利用理化性质及波谱数据(MS、NMR)对其结构进行鉴定,从半育耳蕨体积分数95%的乙醇提取物中分离并鉴定了10个化合物,分别是2R, 3R-3, 5, 6, 7, 8,4′-hexahydroxyflavane(1)、(-)-表儿茶素(2)、(+)-epicatechin(3)、arachniodesin A(4)、4β-carboxymethyl-(-)-epicatechin methyl ester(5)、eriodictyol(6)、daucosterol(7)、3, 4-二羟基苯甲酸乙酯(8)、圣草酚7-O-β-D-(6′-甲酯基)-吡喃葡萄糖醛酸苷(9)、圣草酚7-O-β-D-(6′-乙酯基)-吡喃葡萄糖醛酸苷(10).化合物1~10均为首次从耳蕨属中分离得到.活性测试结果表明,化合物4、5和6对α-葡萄糖苷酶具有较好的抑制活性,其IC_(50)分别为(26.2±1.9)、(32.6±2.5)和(51.5±3.5)μmol·L~(-1).  相似文献   

10.
通过各种分离纯化方法和结构鉴定手段,从仙茅的乙醇提取物中分离鉴定了6个萜类化合物.分别为(3S,5R,6S,7E,9R)-megatigma-7-ene-3,5,6,9-tetrol(1), actinidioionoside(2),(6S,9R)-roseoside(3),(-)-angelicoidenol 2-o-β-D-lucopyranoside (4),(-)-angelicoidenol-2-o-β-apiofuranosyl-(1→6)-β-D-glucopyranoside (5)和tetillapyrone[(7R,9S,10R)-3-methyl-5-(4-hydroxyl-5-hydroxylmethyltetrahydrofuryl)]-6-hydroxypyran-2-one(6).这是首次报道仙茅中的萜类化合物,丰富了仙茅的化学成分.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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