首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 93 毫秒
1.
祁州漏芦中一个新的三萜皂甙   总被引:1,自引:0,他引:1  
从祁州漏芦 (Rhaponticumuniflorum (L .)DC .)的根中分离得到 6个三萜皂甙 ( 1~ 6 ) ,其中化合物 3为一新的三萜皂甙 ,命名为unifloroside,其结构经 1D ,2D_NMR及化学方法鉴定为 3_O_α_L_arabinopyranosyl_urs_9( 11) ,12_dien_2 8_oicacidβ_D_glucopyranosylester。  相似文献   

2.
目的:观察20-羟基蜕皮甾酮对全脑缺血再灌注后SD大鼠海马神经元和认知功能的保护作用,并探讨其相关机制。方法:采用四血管闭塞法建立SD大鼠全脑缺血再灌注模型,脑电图和脑组织Nissl染色评估模型的可靠性。将实验动物分为假手术组,缺血再灌注组和缺血再灌注+20-羟基蜕皮甾酮组。TUNEL染色观察海马神经元凋亡,Morris水迷宫实验评价大鼠的认知功能,酶联免疫法测定缺血再灌注后3-24小时大鼠血清中白细胞介素-1β(IL-1β)和肿瘤坏死因子α(TNF-α)的浓度。结果:全脑缺血再灌注后大鼠海马神经元凋亡率从4.50±1.90%上升至72.90±8.40%(p0.01),给予20和40 mg/kg 20-羟基蜕皮甾酮干预,大鼠海马神经元凋亡率分别下降至51.40±8.60%(p0.05)和42.70±6.80%(p0.01)。与假手术组相比,全脑缺血再灌注后大鼠在Morris水迷宫定位航行试验中逃避潜伏期明显延长(p0.01),在空间探索试验中目标象限停留时间和穿越目标象限次数明显减少(p0.01),而20-羟基蜕皮甾酮显著抑制上述变化,改善大鼠的认知功能。缺血再灌注后3-24小时,大鼠血清中IL-1β和TNFα浓度较假手术组显著升高,20-羟基蜕皮甾酮能抑制上述各时间点大鼠血清中IL-1β和TNFα浓度的升高。结论:20-羟基蜕皮甾酮对全脑缺血再灌注后大鼠海马神经元和认知功能有显著保护作用,抑制缺血再灌注后的炎症反应是其保护机制之一。  相似文献   

3.
β—蜕皮甾酮延缓衰老的初步实验研究   总被引:4,自引:0,他引:4  
观察了β-蜕皮甾酮的抗衰老作用,结果表明,β-蜕皮雷酮能明显延长果蝇寿命,提高大鼠血清SODI知性及GSH-Px活性,降低MDA,提示,β-蜕皮甾酮有一定的抗衰老作用。  相似文献   

4.
采用HPLC技术对云南产鸭跖草科分属于3个族10个属的13种植物中的20-羟基蜕皮甾酮进行分析,结果表明20-羟基蜕皮甾酮广泛存在于已分析的该科植物中,但含量除露水草外均甚微,不具有化学分类学的意义。20-羟基蜕皮甾酮在不同产地和不同生长季节的露水草中的含量变化,则与蝶类昆虫的活动显示有一定的相关性,从而提示20-羟基蜕皮甾酮有可能是露水草与蝶类昆虫协同进化过程的具有化学生态学意义的代谢产物。  相似文献   

5.
露水草中20-羟基蜕皮甾酮的动态变化   总被引:1,自引:0,他引:1  
采用HPLC技术对云南产鸭跖草科分属于3个族10个属的13种植物中的20-羟基蜕皮甾酮进行分析,结果表明20-羟基蜕皮甾酮广泛存在于已分析的该科植物中,但含量除露水草外均甚微,不具有化学分类学的意义。20-羟基蜕皮甾酮在不同产地和不同生长季节的露水草中的含量变化,则与蝶类昆虫的活动显示有一定的相关性,从而提示20-羟基蜕皮甾酮有可能是露水草与蝶类昆虫协同进化过程中的具有化学生态学意义的代谢产物  相似文献   

6.
牛膝种子化学成分研究   总被引:2,自引:2,他引:2  
从牛膝(Achyranthes bidentata Blume.)种子中分离得到8个化合物。通过波谱分析,分别鉴定为N-反式-阿魏酰酪胺(1)、亚油酸甘油酯(2)、β-蜕皮甾酮(3)、水龙骨甾酮B(4)、麦角甾-7,22-二烯-3β,5α,6β-三醇(5)、竹节参皂苷-1(6)、齐墩果酸-3-O-β-D-葡萄糖苷(7)和胡萝卜甙(8)。化合物1、2、5和7为首次从牛膝中分离。  相似文献   

7.
从祁州漏芦(Rhaponticum uniflorum (L.) DC.)的根中分离得到6个三萜皂甙(1~6),其中化合物3为一新的三萜皂甙,命名为unifloroside,其结构经1D, 2D-NMR及化学方法鉴定为3-O-α-L-arabinopyranosyl-urs-9(11),12-dien-28-oic acid β-D-glucopyranosyl ester.  相似文献   

8.
利用Diaion HP 20及硅胶柱层析进行化合物的分离,从乙酸乙酯萃取部位分离得到了4个化合物,借助多种光谱技术进行结构鉴定分别鉴定为(25R)-螺甾-5-烯-1β,3β-二醇1-O{O-α-L-鼠李吡喃糖苷-(1→2)-O-[β-D-木糖吡喃糖苷-(1→3)]1β-D-岩藻吡喃糖苷}(ophiopogonin D,1),(25R)-ruscogenin 1-O-[2-O-(乙酰基)-α-L-鼠李吡喃糖苷-(1→2)][β-D-木糖吡喃糖苷-(1→3)]-β-D-岩藻吡喃糖苷(2),(25R)-rascogenin 1-O-[3-0-(乙酰基)-α-L-鼠李吡喃糖苷-(1→2)][β-D-木糖吡喃糖苷-(1→3)]-β-D-岩藻吡喃糖苷(3),蜕皮甾酮(4).所有化合物均为首次从该植物中分得.  相似文献   

9.
平卧川牛漆甾酮是紫背金盘中的主要植物蜕皮甾类 ,在筋骨草属植物中普遍存在。试验结果表明 ,用 5 0mg L平卧川牛漆甾酮处理小菜蛾卵 ,其孵化受到抑制 ,总孵化率为 94.7% ,显著低于对照的 1 0 0 %孵化。平卧川牛漆甾酮对幼虫具有弱的毒杀活性和良好的拒食活性 ,且与浓度相关。小菜蛾的生长发育也受平卧川牛漆甾酮的影响。用高于 5 0mg L浓度处理幼虫 ,其生长受抑及蛾的产卵量下降 ,而较低浓度处理则有利于幼虫生长 ,卵量提高。这种双重作用可能是由于平卧川牛漆甾酮的激素活性和拒食活性的作用结果 ,后者导致昆虫营养不良。处理幼虫后 ,试虫的化蛹和羽化受阻。小菜蛾对平卧川牛漆甾酮比 2 0 羟基蜕皮酮更敏感。  相似文献   

10.
瑶药红牛膝为苋科植物柳叶牛膝(Achyranthes longifolia)的根及根茎,为瑶族地区习用药材,目前仅有个别省区收载了其质量控制方法。该文对广西壮族自治区区内采集的14批红牛膝药材进行了性状鉴别、显微鉴别和薄层色谱鉴别,并采用飞诺美Gemini-NX C18色谱柱(250 mm × 4.6 mm,5 μm),以乙腈-水溶液(15:85)进行等度洗脱,柱温25 ℃,流速1.0 mL·min-1,检测波长243 nm,建立红牛膝中β-蜕皮甾酮的HPLC含量测定方法。结果表明:(1)红牛膝药材性状、显微鉴别特征明显,显微鉴别可见栓内层、维管束、异常维管束、导管、射线细胞、草酸钙砂晶或方晶等。(2)薄层色谱分离好,β-蜕皮甾酮和人参皂苷RO对应的斑点清晰。(3)含量测定中,β-蜕皮甾酮在5.606~224.224 μg范围内线性关系良好(r=0.999 9),平均加样回收率为97.68%,RSD为1.37%(n=6)。(4)14批样品中β-蜕皮甾酮含量为0.005%~0.158%,平均含量为0.095%。该研究建立了完整的显微鉴别、薄层鉴别及含量测定方法,为合理评价红牛膝质量和临床合理用药提供科学依据。  相似文献   

11.
Two new eudesmane sesquiterpenoids were isolated from the fruits of Daucus carota L. The structures were established based on the interpretation of high-resolution MS and 1D- and 2D-NMR data, the absolute configuration of compound 1 was determined by single-crystal X-ray diffraction. The new compounds were elucidated as (1βH, 3βH, 5βH, 7αH)-4α, 10α-dimethyl-7β-isopropyl-1α, 3α, 4β, 11-tetrahydroxy decahydronaphthalene (1) and (1βH, 3βH, 5βH, 7αH)-4α, 10α-dimethyl-7β-isopropyl-1α, 3α, 4β-trihydroxy decahydronaphthalene-11-O-β-d-glucopyranoside (2). The compound 1 showed significant antioxidant activity.  相似文献   

12.
《Phytochemistry》1987,26(7):2103-2104
Two new sesquiterpene lactones have been isolated from Artemisia maritima and the structures have been assigned on the basis of their spectral properties as 1-oxo-6β,7α,11βH,14β-methylgermacra-4(5)-ene-12,6-olide and 1-oxo-6β,7α,11βH-germacra-4(5),10(14)-dien-12,6-olide.  相似文献   

13.
20-Oxo-5β-[9,12,12-(2)H(3)]pregnan-3α-yl-l-glutamyl 1-ester 11 was synthesized as an internal standard for quantification of a neuroprotective NMDA receptor ligand, 20-oxo-5β-pregnan-3α-yl-l-glutamyl 1-ester 18 and its metabolites, in plasma and tissue. 11α-Hydroxy-progesterone (1) was reduced under basic conditions to yield the corresponding 5β-steroid. Protection of the 3- and 20-oxo groups and oxidation of the 11α-hydroxy group was then followed by a deuterium exchange, conducted under basic conditions using deuterated methanol. Next, the carbonyl moiety at C-11 was reduced and the 11α-hydroxyl group removed through utilization of the Barton-McCombie reaction. Subsequent deprotection of the 3- and 20-acetals and stereoselective reduction of the 3-oxo group gave the desired trideuterated pregnanolone (8). This was coupled with protected glutamic acid, which was then deprotected to yield [9,12,12-(2)H(3)]-pregnanolone glutamate (11) with >99% isotopic purity.  相似文献   

14.
《Phytochemistry》1986,25(8):2003-2004
Two new steroidal alkaloids, solanopubamides A and B, were isolated from the aerial parts of Solanum pubescens. Their structures were elucidated as 3β-formylamino-5α,22αH,25βH-solanidan-23β-ol (solanopubamine A) and 3β-acetylamino-5α,22αH,25βH-solaiiidan-23β-ol (solanopunamide B) by spectral and chemical methods.  相似文献   

15.
Two new saponins, agavasaponin E and agavasaponin H have been isolated from the methanolic extract of Agave americana leaves and their structures elucidated. Agavasaponin E is 3-O-[β-d-xylopyranosyl-(1→2glc1)-α-l-rhamnopyranosyl-(1→4)-α-l-rhamnopyranosyl-(1→3glc 1)-β-d-glucopyranosyl-(1→4)-β-d-glucopyranosyl-(1→4)-α-d-galactopyranosyl]-(25R)-5α-spirostan-12-on-3β-ol, whereas agavasaponin H is 3-O-[β-d-xylopyranosyl-(1→2 glc 1)-α-l-rhamnopyranosyl-(1→4)-α-l-rhamnopyranosyl-(1→3 glc 1)-β-d-glucopyranosyl-(1→4)-β-d-glucopyranosyl-(1→4)-β-d-galactopyranosyl]-26-O-[β-d-glucopyranosyl]-(25R)-5α-furostan-12-on-3β,22α,26-triol.  相似文献   

16.
Integrifolin, the major constituent of Andryala integrifolia, has been isolated and characterized as 3β,8β-dihydroxy-4(15),10(14),11(13)-trien-(1αH), (5αH) guaian-6,12-olide (8-epi-desacylcynaropicrin).  相似文献   

17.
栗柄金粉蕨的黄酮类成分   总被引:3,自引:0,他引:3  
从栗柄金粉蕨( Onychium lucidum ) 地上部分的甲醇抽提物中分到10 个成分, 经详细的一维、二维核磁数据分析, 它们被鉴定为: 木犀草甙(1) , 3 , 7 - 二甲基槲皮素(2) , 高山甙B (3) , 金粉蕨素(4) , 栗柄醇(5) , 金粉蕨醇B(6) , β- 谷甾醇(7) , 胡萝卜甙(8) ,齐墩果酸(9) 和蔗糖(10) 。栗柄醇系新成分。1 , 2, 9 系首次由金粉蕨属分到。  相似文献   

18.
A new phenolic glycoside, named syringic acid-4-O-α-L-rhamnopyranoside (1), together with three known compounds were isolated from the MeOH extract of the whole plants of Chloranthus multistachys. Their structures were elucidated on the basis of extensive spectroscopic. To the best of our knowledge, the three known compounds, 1β,4β-dihydroxy-5α, 8β(H)-eudesm-7 (11) Z-en-8, 12-olide (2), 1β, 4α-dihydroxy-5α, 8β(H)-eudesm-7 (11) Z-en 8, 12-olide (3), and (–) (7S,8R) dihydrodehydrodiconifery alcohol (4) were all isolated from this plant for the first time.  相似文献   

19.
17α-Hydroxy-17β-methyl-5β-androstan-3-one, 17μ-methyl-5α-androstane-3α, 17α-diol, 17β-methyl-5α-androstane-3β, 17α-diol, 17α-methyl-5β-androstane-3β, 17β-diol, 17β-methyl-5β-androstane-3α, 17α-diol and 17β-methy1–5β-androstane-3β, 17α-diol were synthesized for the first time. 1H NMR spectra of all four 17ξ-hydroxy/17ξ-methyl C-3 ketones and all eight C-3 alcohols were recorded in chloroform-d and pyridine-d5. Pyridine-induced chemical shifts are discussed. Thin-layer Chromatographic data are given.  相似文献   

20.
Certain Helicobacter pylori strains adhere to the human gastric epithelium using the blood group antigen-binding adhesin (BabA). All BabA-expressing H. pylori strains bind to the blood group O determinants on type 1 core chains, i.e. to the Lewis b antigen (Fucα2Galβ3(Fucα4)GlcNAc; Le(b)) and the H type 1 determinant (Fucα2Galβ3GlcNAc). Recently, BabA strains have been categorized into those recognizing only Le(b) and H type 1 determinants (designated specialist strains) and those that also bind to A and B type 1 determinants (designated generalist strains). Here, the structural requirements for carbohydrate recognition by generalist and specialist BabA were further explored by binding of these types of strains to a panel of different glycosphingolipids. Three glycosphingolipids recognized by both specialist and generalist BabA were isolated from the small intestine of a blood group O pig and characterized by mass spectrometry and proton NMR as H type 1 pentaglycosylceramide (Fucα2Galβ3GlcNAcβ3Galβ4Glcβ1Cer), Globo H hexaglycosylceramide (Fucα2Galβ3GalNAcβ3Galα4Galβ4Glcβ1Cer), and a mixture of three complex glycosphingolipids (Fucα2Galβ4GlcNAcβ6(Fucα2Galβ3GlcNAcβ3)Galβ3GlcNAcβ3Galβ4Glcβ1Cer, Fucα2Galβ3GlcNAcβ6(Fucα2Galβ3GlcNAcβ3)Galβ3GlcNAcβ3Galβ4Glcβ1Cer, and Fucα2Galβ4(Fucα3)GlcNAcβ6(Fucα2Galβ3GlcNAcβ3)Galβ3GlcNAcβ3Galβ4Glcβ1Cer). In addition to the binding of both strains to the Globo H hexaglycosylceramide, i.e. a blood group O determinant on a type 4 core chain, the generalist strain bound to the Globo A heptaglycosylceramide (GalNAcα3(Fucα2)Galβ3GalNAcβ3Galα4Galβ4Glcβ1Cer), i.e. a blood group A determinant on a type 4 core chain. The binding of BabA to the two sets of isoreceptors is due to conformational similarities of the terminal disaccharides of H type 1 and Globo H and of the terminal trisaccharides of A type 1 and Globo A.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号