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1.
风干的黄姜花(Hedychium flavum)根茎粉碎后,用工业甲醇浸泡提取。提取物水溶后 用乙酸乙酯萃取,乙酸乙酯萃取部分利用柱层析和HPLC等方法进行分离,经NMR等方法鉴定后, 得到4个二芳基庚烷类化合物,化合物分别为:1,7-bis(4-hydroxy-3-methoxyphenyl)heptane-3,5- diol (1)、5-hydroxy- 1-(4''-hydroxyphenyl)-7-(4''- hydroxy-3''-methoxyphenyl)-3-heptanone (2)、 gingerenone A (3)和coriandralpinin C (4),均为首次从黄姜花中分离得到。  相似文献   

2.
将干燥柳蒿用甲醇室温浸泡提取,提取液浓缩后依次用正己烷、乙酸乙酯和正丁醇萃取,制得相应溶剂萃取物,利用硅胶柱色谱及HPLC等分离纯化,从乙酸乙酯萃取物中分离得到4种单一化合物,依据理化性质及波谱数据分析,分别鉴定为:香豆素(1),7-甲氧基香豆素(2),5-羟基-6,7,3′,4′-四甲氧基黄酮(3),trans-5-hydroxy-2-isopropenyl-5-methylhex-3-en-1-ol(4)。其中,化合物1,3,4为首次从柳蒿中分离得到。  相似文献   

3.
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   

4.
为研究飞扬草的化学成分,利用溶剂提取法,正、反相硅胶柱和半制备高效液相色谱法对其乙酸乙酯提取物进行分离纯化,从飞扬草乙酸乙酯提取物分离得到11个化合物,并根据理化性质和波谱技术进行结构鉴定,分别鉴定为蒲公英萜醇 (1)、蒲公英赛酮 (2)、cycloart-23-ene-3β,25-diol (3)、25-hydroperoxycycloart-23-en-3β-ol (4)、吐叶醇 (5)、黑麦草内酯 (6)、β-谷甾醇 (7)、cucurbic acid (8)、9, 16-二羰基-10, 12, 14-三烯-十八碳酸 (9)、3-烯-十六碳酸 (10)、正二十四碳酸 (11).其中化合物5、化合物9~化合物11为首次从飞扬草中分离得到.  相似文献   

5.
对云南油杉来源的内生真菌Pleosporales sp. SSJ-1进行化学表观遗传修饰并研究其次生代谢产物.利用组蛋白去乙酰化酶抑制剂恩替诺特(Entinostat)对菌株Pleosporales sp. SSJ-1进行诱导,采用正相硅胶柱色谱、ODS反相柱色谱和半制备型高效液相色谱等手段对粗提物进行分离纯化,通过NMR、质谱、旋光等进行结构解析.从菌株Pleosporales sp. SSJ-1的诱导发酵物中分离得到6个化合物,其中化合物1为新化合物.分别鉴定为(2S,4R)-2,3-dihydro-2-methyl-benzopyran-4,5-diol(1)、(4S)-4,8-dihydroxy-α-tetralone(2)、(R)-2,3-dihydro-5-hydroxy-2-methylchromen-4-one(3)、(2R,4R)-3,4-dihydro-4-methoxy-2-methyl-2H-chromen-5-ol(4)、(R)-2,3-dihydro-5-methoxy-2-methylchromen-4-one(5)、(2R,4S)-5-methoxy-2...  相似文献   

6.
长柱金花茶化学成分研究   总被引:1,自引:0,他引:1  
【目的】研究长柱金花茶(Camellia nitidissimavar.longistyla)叶中的化学成分。【方法】利用硅胶吸附色谱法、薄层色谱法、高效液相制备色谱法、重结晶法等技术对样品进行分离和纯化,通过~1H-NMR、~(13)C-NMR、MS等波谱方法对化合物进行结构鉴定。【结果】鉴定出8个化合物的结构,分别为豆甾醇(stigmasterol)(1)、stigmast-7-en-3-ol(2)、落新妇苷(3)、5,7-二羟基色原酮-3-O-α-L-吡喃鼠李糖苷(eucryphin)(4)、槲皮素-3-O-α-L-吡喃鼠李糖苷(5)、槲皮素-3-O-D-吡喃葡萄糖苷(6)、棕榈酸(7)、3β-acetoxy-6a,13β-dihydroxyolean-7-one(8)。【结论】除豆甾醇(stigmasterol)外,其余7个化合物均为首次从该品种植物中分离出来。  相似文献   

7.
采用色谱分离手段对紫红獐牙菜(Swertia punicea Hemsl.)的乙醇提取物进行分离纯化,研究其化学成分,并运用1H NMR、13C NMR等波谱方法和文献数据对比鉴定化合物结构,从紫红獐牙菜全草中得到8个已知化合物,分别鉴定为:1,5-二羟基-2,3,4-三甲氧基酮(1)、1,7-二羟基-2,3,5-三甲基酮(2)、5,7,4'-三羟基黄酮(3)、β-谷甾醇(4)、豆甾醇(5)、2,5-di-O-β-D-glucopyranosyloxy-1,3-dimethoxybenzene(6)、7-(3-hydroxy-5-methoxyphenyl)propane-7,8,9-triol(7)、1-tetratriacontanol(8).  相似文献   

8.
姜花( Hedychium coronarium Koen)根茎用甲醇提取,利用硅胶柱层析、Sephadex LH-20 柱层析、薄层层析及HPLC等手段对其化学成分进行分离纯化,得到5个化合物,经波谱解析和对 其理化性质进行对比,鉴定为3个二芳基庚烷和2个黄酮,分别是gingerenone A(1 1),rel-(3 R ,5 S )-3, 5-dihydroxy-1-(4-hydroxy-3-methoxyphenyl)-7-(4-hydroxyphenyl)-heptane(2 2),hexahydrocurcumin (3 3),3,5,7,4´-tetramethoxyflavone(4 4)和5-hydroxy-3,7,4´-trimethoxyflavone(5 5)。化合物1 1~4 4为 首次从姜花中分离得到。  相似文献   

9.
槐(Sophora japonica)豆荚用甲醇提取,采用硅胶柱层析、Sephadex LH-20凝胶柱层析、MCI柱层析和反相柱层析进行化学成分分离纯化,从中分离得到8个化合物。根据波谱分析和理化性质对化合物结构进行鉴定,鉴定结构为山柰酚(1)、山柰酚3-O-β-槐糖苷(2)、山柰酚3-O-α-L-鼠李糖基(1→6)-β-D-葡萄糖苷(3)、山柰酚3-O-α-L-鼠李糖基(1→4)-β-D-葡萄糖苷(4)、山柰酚3-O-α-L-鼠李糖苷-7-O-β-D-葡萄糖苷(5)、染料木素(6)、染料木苷(7)和槐属双苷(8)。其中,化合物4和5为首次从槐属植物中离得到,化合物2和7为首次从该植物中分离得到。  相似文献   

10.
采用硅胶柱色谱法对蒙古黄芪花提取物进行分离,结合MS,1 H-NMR等波谱手段鉴定化合物的结构,以紫外分光光度法测定分离化合物的抗氧化能力。共分离鉴定出8种化合物,分别为:(1)金丝桃苷,(2)异槲皮苷,(3)7-甲氧基-山萘酚-3-O-半乳糖苷,(4)7-甲氧基-山萘酚-3-O-葡萄糖苷,(5)7-甲氧基-山萘酚-3-O-(6"-O-丙二酰基)-β-D-葡萄糖苷,(6)紫云英苷,(7)异鼠李素-3-O-β-D-吡喃葡萄糖苷,(8)毛蕊异黄酮。其中化合物(3)(4)(5)(7)为首次从黄芪属中分离得到。测定了黄芪花不同粗提物及纯成分的抗氧化活性,其中金丝桃苷与异槲皮苷抗氧化活性最强。  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.
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   

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 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   

15.
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   

16.
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   

17.
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   

18.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

19.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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