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1.
采用硅胶柱层析、ODS 反相柱层析、Sephadex LH-20 凝胶柱层析、半制备高效液相 HPLC等色谱分离方法对薜荔(Ficus pumila)叶80%乙醇提取物进行分离纯化,得到7个化合物。 根据化合物的理化性质和核磁共振波谱数据比对文献,分别鉴定为:3-hydroxy-damascone (1),月 桂酸乙酯(2),马桑酸(3),13-hydroxy-(9Z,11E,15E)-octadecatrienoic acid (4),乙基-β-D-吡喃 葡萄糖苷(5),苄醇-β-D-葡萄糖苷(6)和2-[4-(3-hydroxypropyl)-2-methoxyphenoxy]-propane- 1,3-diol (7)。其中化合物7为首次从该属植物中分离得到,化合物1为首次从该植物中分离得到。 抗肿瘤活性测试结果表明,化合物 1 对 A549 细胞显示出一定的抑制活性,IC50值为 32.21 µg/mL。 抗菌活性测试结果表明,所有化合物对测试的4株人体致病菌和2株弧菌均无明显抗菌活性。  相似文献   

2.
从大戟科植物棒柄花(Cleidion brevipetiolatum Pax et Hoffm.)中分离得一化合物,经理化常数、UV、IR、^1HNMR ^13CNMR、MS等波谱测试和解析,鉴定为反式4-(1-丙烯基)-苯酚-β-D-吡喃葡萄糖苷。该化合物是首次从该植物中分离鉴定。  相似文献   

3.
苯乙酰异谷酰胺作为抗癌酮(Antineoplaston A10)在体内的一种降解产物,具有一定程度的抗肿瘤活性。为此设计并合成了一些新的苯乙酰异谷氨酰胺类化合物以测试其抗肿瘤活性。合成中采用在酸性条件下,先选择性地对L-谷氨酸γ位羧基进行酯化,再进一步合成目标化合物,反应条件温和,收率好。所合成化合物结构经IR、^1HNMR及元素分析鉴定,对所合成的目标化合物的抗肿瘤活性采用MTT法对体外培养的乳腺癌细胞成活率进行了测试,初步结果显示有一定抑制肿瘤细胞存活的作用。  相似文献   

4.
对一株红树植物红榄李(Lumnitzera littorea(Jacq.) Voigt)内生真菌Penicillium oxalicum HLLG-13次级代谢产物进行系统研究;综合运用多种色谱分离方法结合波谱、光谱技术从中分离 鉴定了21个单体化合物,分别为2-(4-羟苯基)乙基-(2S)-羟基丙酸(1),2-(4-羟苯基)乙酸乙酯 (2),(4-羟 苯 基)乙 酸 甲 酯(3),4-羟 基 苯 乙 醇(4),2,4,5-三 甲 基 间 苯 二 酚(5),1-(2,6- dihydroxyphenyl) butan-1-one(6),rosmarinosin C(7),penicyclone A(8),penicyclone C(9),2-(N-乙 酰氨基)苯酚(10),N-乙酰酪胺(11),2-[[(2S)-羟基-1-氧丙基]氨基]苯甲酰胺(12),peniamidone A(13),meleagrin(14),7-羟基-2-(2ʹS-羟丙基)-5-甲基色酮(15),3-甲基-6,8-二羟基异香豆素 (16),(-)-6-hydroxymellein(17),(3R)-甲基-5-氯-6,8-二羟基-二氢异香豆素(18),(3R)-甲基-6, 8-二羟基-7-甲氧基-二氢异香豆素(19),(-)-citreoisocoumarinol(20)和 de-O-methyldiaporthin (21)。抗菌活性测试结果表明,所有化合物对测试的5株人体致病菌和3株弧菌均无明显抗菌活 性;神经保护活性测试结果表明,化合物16具有中等的神经保护活性,在200 µmol/L浓度下,可以 将H2O2氧化损伤的HT22细胞存活率由43.36%提升至60.15%。  相似文献   

5.
鬼箭锦鸡儿细胞毒活性成分研究   总被引:2,自引:0,他引:2  
 运用中压柱色谱和高效制备液相色谱方法对藏药鬼箭锦鸡儿的化学成分进行分离纯化,利用现代波谱技术鉴定所分离化合物的结构,并对所得到的化合物进行体外抗肝癌活性测试.从鬼箭锦鸡儿乙醇提取物中分离得到8个单体化合物,分别鉴定为6,7,3′-三羟基-4′-甲氧基异黄酮(1)、3,7-二羟基-4′-甲氧基黄酮(2)、3-甲氧基-4,9-二羟基紫檀素(3)、7,3′-二羟基-5′-甲氧基异黄酮(4)、6,7-二羟基-4′-甲氧基异黄酮(5)、3,9-二甲氧基-8-羟基紫檀素(6)、3,9-二甲氧基-4-羟基紫檀素(7)和3-甲氧基-4-羟基高丽槐素(8),所有的化合物为首次从该植物中分离得到.采用MTT法对化合物1~8进行体外抗肝癌活性测试,结果显示所有的化合物对2个肝癌细胞株HepG2和Hep3B均有抑制作用,它们的IC50值范围为22.5~104.7μg/mL.  相似文献   

6.
间苯二甲酸与3-芳基-4-氨基-5-巯基-1,2,4-三氮唑(1a~1h)在相转移催化剂四丁基碘化铵和POCl3作用下,高产率制得8种1,3-双[3-芳基-1,2,4.三唑并[3,4.b]-1,3,4-噻二唑-6-基]苯类衍生物(2a-2h),并利用IR、^1H NMR、MS和元素分析对目标化合物的结构进行了表征.初步的抗菌试验表明,部分目标化合物表现出较好的抑菌活性.  相似文献   

7.
合成抗癌药物中间体脂肪胺取代的蒽醌类化合物,并对其进行体外抗癌活性测试.以1,4,5,8-四羟基蒽醌隐色体和脂肪胺为原料,在氮气保护下进行缩合反应,然后通过氧化合成目标化合物.对目标化合物利用红外光谱和核磁共振氢谱进行表征.体外抗癌活性测试表明化合物1,4-二[2-(二甲氨基)-乙氨基]-5,8-二羟基蒽醌有较强的抗癌活性.  相似文献   

8.
合成一系列新的5-(1-苯基-5-甲基-1,2,3-唑-4-基)-4-芳基-1,2,4-三唑-3-硫基乙酸,所有化合物均经元素分析和波谱数据予以鉴定,对代表性化合物作了抗菌活性测试,结果表明它们都表现出不同程度的抗菌活性。  相似文献   

9.
5-去氢枞基-1,3,4-噁二唑-2-硫醇的微波合成及抗菌活性   总被引:4,自引:2,他引:2  
以去氢枞酸为原料,经酰化后与水合肼反应合成去氢枞酸酰肼.在微波辐照下,去氢枞酸酰肼与二硫化碳在碱性条件下环合制得5-去氢枞基-1,3,4-噁二唑-2-硫醇.通过元素分析、IR、MS、1H NMR和13C NMR对所合成化合物进行了结构表征.体外抗菌活性测试结果表明,该化合物对革兰氏阳性菌-金黄色葡萄球菌、革兰氏阴性菌-大肠杆菌和枯草杆菌均有较强的抗菌活性,其最低抑菌浓度(MIC)分别为4,8和4/μg/mL.  相似文献   

10.
对莲叶桐(Hernandia ovigeraL.)树枝的化学成分进行了研究。应用硅胶、凝胶Sephadex LH-20等柱色谱技术进行分离纯化,运用现代波谱技术(EI—MS,1HNMR,13CNMR)进行结构的鉴定,并对结构新颖的化合物进行活性研究。结果从莲叶桐中分离得到6个化合物。化合物鉴定分别是Tetrahydrofurofuranlignan 5-[(1S,3aR,4S,6aR)-4-(3,4,5-trimethoxyphenyl)-hexahydrofuror3,4-elfuran-1-v1]-2H-1,3-benzo—dioxole(1)、Yatein(2)、去氧鬼臼毒素(3)、6p羟基-胆甾-4-烯-3-酮(4)、(3β,5α,6β,22E)-Ergosterol-△^8,14,22-Diene-3,5,6-triol(5)、伊谷甾醇(6),化合物(1)~(3)具有很强的抗肿瘤活性。所得化合物均为首次从莲叶桐树枝中分离得到。  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 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   

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.
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   

17.
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   

18.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

19.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

20.
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   

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