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1.
Two new sulfated steroidal pentaglycosides (asterosaponins), novaeguinosides Ⅰ (2) and Ⅱ(3), along with the known regularoside B (1) were isolated from the starfish Culcita novaeguineae. Their structures were elucidated by extensive NMR techniques as well as chemical evidence. The new asterosaponins showed marginal in vitro cytotoxicity against two human tumor cell lines.  相似文献   

2.
Bioassay-guided fractionation of the active n-BuOH extract of the starfish Culcita novaeguineae resulted in the isolation of three new sulfated steroidal glycosides (asterosaponins) 1, 2 and 3, as active compounds causing morphological abnormality of Pyricularia oryzae mycelia. Compounds 1-3 possess the same pentasaccharide moiety, beta-D-fucopyranosyl-(1→2)-alpha-L-arabinopyranosyl- ( 1 → 4 )-[- beta-D- quinovopyranosyl- ( 1 →2 ) ]-beta-D-xylopyranosyl- ( 1 → 3 )-beta-D-quinovopyranosyl, linked to C-6 of 3beta-sulfated steroidal aglycones and differ from each other in the side chains.  相似文献   

3.
近年来,药物研究已 进入立体异体水平,研究药异构体与生活之间的关系已引起人们的日益重视。本文概述了几个主要立体异构因素,重点讨论了旋光性药物对对映体与生物活性之间的关系,并对一些具有代表性的药物加以介绍。  相似文献   

4.
中草药是祖国医药学宝库中一颗璀璨的明珠,是天然药物的重要领域,是人类的共同财富。几千年来,祖国的传统医药为炎黄子孙的生息、繁衍做出了不可磨灭的贡献。随着近代科学技术的发展,为中药学研究注入了新的活力,同时也面临新的机遇和挑战。中药研究不应再囿有窠臼,要应用现代  相似文献   

5.
香附化学成分的分离及对未孕大鼠离体子宫肌收缩的影响   总被引:11,自引:0,他引:11  
香附为莎草科植物莎草Cyperus rotundus Linn.的干燥根茎.为常用中药,具有引气解郁,调经解痛的功效.  相似文献   

6.
To evaluate the antioxidant activities of different chemical constituents from Astragalus mongholicus Bunge and their protection against xanthine (XA)/xanthine oxidase (XO)-induced toxicity in PC12 cells. Methods The compounds of Astragalus mongholicus Bunge were isolated by chromatography and the structures were elucidated on the basis of spectral data interpretation. Their antioxidant activities were detected by 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities in a cell-free system. Meanwhile, the effects against XA/XO-induced toxicity were assessed using MTT assay in PC12 cells. Results Ten principal constituents were isolated and identified as formononetin (Ⅰ), ononin (Ⅱ), calycosin (Ⅲ), calycosin-7-O-β-D-glucoside (Ⅳ), 9,10-dimethoxypterocarpan-3-O-β-D-glucoside (Ⅴ), adenosine (Ⅵ), pinitol (Ⅶ), daucosterol (Ⅷ), β-sitoster (Ⅸ) and saccharose (Ⅹ) from Astragalus mongholicus Bunge. The compounds Ⅰ, Ⅲ, and Ⅳ scavenged DPPH free radicals in vitro. Formononetin and calycosin were found to inhibit XA/XO-induced cell injury significantly, with an estimated EC50 of 50 ng/mL. Conclusion Compound Ⅲ, Ⅵ, and Ⅶ are first reported in this plant. Calycosin exhibits the most potent antioxidant activity both in the cell-free system and in the cell system.  相似文献   

7.
苔藓植物的化学活性成分研究概况   总被引:11,自引:0,他引:11  
1 前言  苔藓植物是植物界中的一个重要门类 ,属于低等植物 ,约占全世界植物总数的 5 %。从分类学角度可将苔藓植物分为三类 :角苔纲 (Hornworts)、苔纲 (L iverworts)、藓纲(Mosses)。大约在 30 0万年前 ,地球上就有了苔藓 ,比有花植物早了约 2 0 0万年。苔藓分布很广 ,能适应多种气候环境 ,世界各处几乎都有分布 ,尤其多生于阴暗潮湿地区 ,如热带雨林和山林 ,特别是土坡、沟边或沼泽地等。苔藓植物虽然分布面积较广 ,但密度较小 ,种间杂生 ,不易区别和分离 ,难以大量采集 ,对其进行化学成分的研究长期受到忽视 ,直到近 30年来 ,随着…  相似文献   

8.
日前,江苏省人事厅下发了关于资助博士后科研项目的通知。药物化学专业博士后研究人员王进欣博士、陈敏东博士分别入选2004年度“江苏省博士后科研资助计划”。其中王进欣博士的项目“天然产物藤黄酸的化学结构修饰及其衍生物的合成与生物活性研究”获3万元资助;程敏东博士的项目“p91024新药的不对称合成及拆分研究”获1万元资助。  相似文献   

9.
This study is designed to evaluate antioxidant and antigenotoxic activities of corn tassel extracts(CTTs). The major bioactive components of CTTs include flavonoid, saponin and polysaccharide. The antioxidant properties of the three bioactive components of CTTs were investigated by Ferric Reducing Antioxidant Property(FRAP) and 1, 1-diphenyl-2-picrylhydrazyl(DPPH) assays. The activities of the extracts were determined by assessing the inhibition of mutagenicity of the direct-acting mutagen fenaminosulf, sodium azide, and indirect-acting mutagen 2-aminofluorene using the Ames test(strains TA98 and TA100). The results showed that the extraction rates of flavonoid, saponin, and polysaccharide from the dried corn tassels were 1.67%, 2.41% and 4.76% respectively. DPPH and FRAP assay strongly demonstrated that CTTs had antioxidant properties. CTTs at doses of 625, 1250 and 2500 μg per plate reduced 2-aminofluorene mutagenicity by 12.52%, 28.76% and 36.49% in Salmonella typhimurium TA98 strain assay respectively and by 10.98%, 25.27% and 37.83%, at the same doses in Salmonella typhimurium TA100 assay system, respectively. 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide(MTT) assay showed that the different concentrations of CTTs inhibited the proliferation of MGC80-3 cells in a dose-dependent manner(P0.01). It is concluded that these integrated approaches to antioxidant and antigenotoxicity assessment may be useful to study corn tassel as a natural herbal material.  相似文献   

10.
Radix Isatidisis one of the most commonlyused antipyretic and detoxicant agents in tradition-al Chinese medicine.Its original source was identi-fied to be the dried roots ofIsatidis indigoticaFort.(Cruciferae).The antipyretic and detoxicantagents in traditional Chinese medicine are a type ofsynthetic therapeutic medicine.It can comprehen-sively activate the ability of anti-infection and re-pair of the human body.There are many pharma-cological effects such as antibacteria,antivirus,antipyre…  相似文献   

11.
目的 研究西南银莲花Anemone davidii根状茎和地上部分的活性三萜皂苷。方法 用甲醇室温提取,大孔树脂D101、硅胶及反相硅胶柱层析分离纯化,NMR分析并结合化学降解鉴定结构,体外抑菌和人癌细胞生长抑制实验测试抗菌和抗癌活性。结果 从该植物根状茎中分离鉴定出三萜皂苷Ⅰ~Ⅶ,从地上部分分离鉴定出三萜皂苷Ⅴ~Ⅷ,其中Ⅱ~Ⅳ对人癌细胞体外生长有抑制作用,Ⅴ,Ⅵ和Ⅷ有一定的抗菌活性。结论上述化学成分均为首次从该植物中分离得到,并首次进行抗癌活性测试,其中Ⅱ,Ⅳ和Ⅵ在该属植物中为首次报道。  相似文献   

12.
Kinsenoside is a main active component isolated from plants of the genus Anoectochilus, and exhibits many biological activities and pharmacological effects, including hepatoprotective, anti-hyperglycemic, anti-hyperliposis, anti-inflammatory, vascular protective and anti-osteoporosis effects and so on, which is contributing to its promising potency in disease treatments. This review aims to recapitulate the pharmacological functions of kinsenoside, as well as its source, extraction, identification, quantitative analysis, pharmacokinetics, synthesis and patent information. The data reported in this work can confirm the therapeutic potential of kinsenoside and provide useful information for further new drug development.  相似文献   

13.
东海微生物中6种环二肽类天然活性物质的分离和鉴定   总被引:5,自引:1,他引:4  
目的:从海洋微生物中寻找天然活性物质.方法:利用稻瘟霉作为菌株筛选模型,对筛选出来的活性菌株F8712发酵液的醋酸乙酯提取物进行化合物分离;通过1HNMR、13CNMR和ESI-MS对化合物进行结构鉴定.结果和讨论:鉴定了6个环二肽类化合物,它们分别为环[Ala-Leu](Ⅰ),环[Ala-Ile](Ⅱ),环[Val-Pro](Ⅲ),环[Leu-Pro](Ⅳ),环[Ile-Pro](Ⅴ)和环[Leu-Val](Ⅵ).这些环二肽都没有抗稻瘟霉活性,化合物Ⅴ对鳗弧菌(Vibrio anguillarm)具有较强的抑制能力,其MIC为0.07 μg/ml.  相似文献   

14.
15.
目的 研究秋花独蒜兰化学成分,发现其活性成分。方法 秋花独蒜兰经95%乙醇提取、硅胶柱层析、半制备HPLC和Sephadex LH-20柱层析进行分离纯化,波谱分析(核磁共振氢谱、碳谱、和质谱)确定结构;应用MTT法,对部分化合物进行体外抗肿瘤活性筛选。结果 从秋花独蒜兰分离鉴定10个化合物,分别为:1, 7-dihydroxy-2, 5-dimethoxyphenanthrene(1), 2, 7-dihydroxy-1, 5-dime-thoxyphenanthrene(2),confusarin (3),4,7-dihydroxy-2-dimethoxy-9,10-dihydrophe-nanthrene (4),pleionesin B (5),pleionesin C (6),flavanthrin (7),2,2′-dihydroxy-5,5′,7,7′-tetramethoxy-9,9′,10,10′-tetrahydro-3,3′-biphenanthrene (8),6,6′,7,7′-tetrahy--droxy-2,2′,4,4′-tetramethoxy-8,8...  相似文献   

16.
目的 研究杜鹃兰化学成分,发现其抗肿瘤活性成分。方法 杜鹃兰经95%乙醇提取、硅胶柱层析、半制备HPLC和Sephadex LH-20柱层析进行分离纯化,波谱分析(核磁共振氢谱、碳谱、和质谱)确定结构;应用MTT法,对部分化合物进行体外抗肿瘤活性筛选。结果 从杜鹃兰分离鉴定12个化合物,分别为bisbenzopyran (1),(22E)-ergosta-6, 22-dien-3β, 5α, 8α-triol (2), 3β-hydroxycholesta-5-ene (3), β-sistosterol (4),pinoresinol (5),5,4′-dihydroxy-7-(4-hydroxybenzoyl)-3′-methoxyflavone (6),4-methoxy-2,3,7-trihydroxyphenanthrene(7), 2-hydroxy-4, 7-dimethoxyphenanthrene(8), 4, 4′-dimethoxy-[1, 1′-biphenanthrene]-2,2′,7,7′-tetrol (9),4,7,4′,9′-tetramethoxy...  相似文献   

17.
麦仙翁中促进小麦增产的活性氨基酸成分研究   总被引:1,自引:0,他引:1  
对麦仙翁(AgrostemmagithagoL.)种子和全草中促进小麦增产的活性氨基酸部位中的游离氨基酸成分进行了分析。结果表明种子中活性氨基酸部位含有19种氨基酸,其中以苯丙氨酸含量为最高;全草中的活性氨基酸部位中含有17种氨基酸,以脯氨酸为最高。还探讨了氨基酸组成的比例与促进小麦增产的关系。  相似文献   

18.
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