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81.
从丝叶唐松草根中分得一新的三萜皂甙,命名为thalifoenoside A,根据光谱和化学方法确定其结构为3β,22(S),27-三羟基-24-烯-环菠萝蜜烷,3-O-β-D-鸡纳糖基-(1→2)-α-L-鼠李糖基-(1→6)-β-D-(4-乙酰基)-葡萄糖甙,其甙元亦为一新的化合物。此外还分到3个已知物thalifendlerine,N-methylcorydaldine,β-谷甾醇。  相似文献   
82.
目的 研究僵蚕的化学成分,并对从僵蚕中分离得到的一个新的香豆素苷类成分进行结构鉴定。方法 应用硅胶、Sephdex LH-20柱色谱和重结晶等方法进行分离,利用光谱方法对分离得到的单体成分进行结构鉴定。结果 分离并鉴定出8个化合物分别为:6-甲氧基-7-O—β—D-(4′-甲氧基)吡喃葡萄糖基香豆素[6-methoxy-7-O—β-D-(4′-methoxy)glucopyranosyl coumarin,Ⅰ]、麦角甾-6,22-二烯3β,5α,8α-三醇(ergost-6,22-dien-3β,5α,8α—triol,Ⅱ)、棕榈酸(palmidcacid,Ⅲ)、赤藓醇(meso—erythritol,Ⅳ)、甘露糖醇(D-mannitol,Ⅴ)、尿嘧啶(uracil,Ⅵ)、β-谷甾醇(β-sitosterol,Ⅶ)、胡萝卜苷(daucosterol,Ⅷ)。结论 化合物Ⅰ为新香豆素苷化合物。  相似文献   
83.
张虎翼  潘竞先 《中国药学》1996,5(2):105-108
从醉鱼草属植物密蒙花的花蕾中分离得到6个苯丙素酚甙类成分,分别鉴定为verbascoside(1),cistanoside F(2),β-hydroxyacteoside(3),poliumoside(4),echinacoside(5),martynoside(6),它们在体外实验中显示了一定的抗肿瘤活性,同时还分离得到两个黄酮甙:蒙花甙(7)和芹菜素-7-芦丁糖甙(8)。其中化合物(2),(3),(4),(8)为首次从醉鱼草属中分离得到。  相似文献   
84.
A new flavonol galloylrhamnoside, kaempferol 3-O-(2″,3″-di-O-galloyl)-α-l-rhamnopyranoside, and a new lignan glycoside, hinokinin 7-O-β-d-glucopyranoside were isolated from the leaves of Koelreuteria henryi, along with 18 known compounds, including six flavonol glycosides (38), three lignans (911), four chlorophyll derivatives (1215), two steroids (16, 17), and three aromatic compounds (1820). The structures were determined on the basis of spectral analysis and chemical evidence. The scavenging effect of 18 and 20 on the stable free radical 1,1-diphenyl-2-picrylhydrazyl was examined. Compounds 1, 5, 6, and 20 showed more potent activity than that of trolox.  相似文献   
85.
A new saponin, 3-O-[a-L-rhamnopyranosyl(1→2)-β-D-glucopyranosyl(1→2)-β-D-glucuronopyranosyl]soyasapogenol B carboxylate (6) has been isolated from the medicinal plant yellow sweetclover together with azukisaponin II(7), robinin(8), and clovin(9). 7, 8, and9 are reported for the first time from this plant. The new saponin(6) exhibited inhibitory action on leucocyte migration in inflammation.  相似文献   
86.
Antibacterial activity-guided fractionation of the CHCI3-MeOH (1:1) extract of Paeonia suffruticosa root bark furnished three monoterpene glycosides, 6-O-vanillyoxypaeoniflorin (1), mudanpioside-H (2), and galloyl-oxypaeoniflorin (3). Of the isolated compounds, compound 1 is a new compound. All isolated compounds showed broad, but moderate, antibacterial activity with minimum inhibitory concentration (MIC) values in the range of 100 to 500 microg/mL against eighteen pathogenic microorganisms of concern for public health or zoonosis.  相似文献   
87.
Two new phenolic glycosides, ilexpubsides A and B, along with four known lignan glycosides were isolated from the roots of Ilex pubescens. By spectral evidence, the structures of the new compounds were elucidated as 4-O-β-D-[6'-O-(4'-O-β-D-glucopyranosylvanilloyl)glucopyranosyl] vanillic acid (1) and syringinic 6'-O-β-D-xylopyranoside (2). The known compounds were identified to be liriodendrin (3), (-)-olivil (4), tortoside A (5) and (+)-cyclo-olivil (6). All compounds were first isolated from Ilex pubescens.  相似文献   
88.
A new phenolic triglycoside, dolichandroside, was isolated from the branches of Dolichandrone serrulata together with decaffeoyl-verbascoside, verbascoside, isoverbascoside, markhamioside A, 2-O-apiosylverbascoside, luteoside B and ixoside. The structure elucidations were based on analyses of spectroscopic data.  相似文献   
89.
Besarani D  Wu C  Fry CH 《BJU international》2006,97(5):1083-1086
OBJECTIVE: To determine the role of Na+-Ca2+ exchange in the regulation of isolated detrusor smooth muscle contractility. MATERIALS AND METHODS: Isolated guinea-pig detrusor strips were used to record isometric tension generated by; (a) electrical-field stimulation to elicit nerve-mediated responses; and (b) adding carbachol or superfusing with a high-K+ solution. The [Na+] gradient between extracellular and intracellular compartments was altered by: (i) reducing superfusate [Na+] in stages from 140.2 to 10.2 mm; (ii) addition of the cardiac glycoside strophanthidin (200 microm). RESULTS Reducing extracellular [Na+] reversibly reduced the magnitude of nerve-mediated contractions but increased the resting tension and magnitude of carbachol-induced contracture. The mean (sd) [Na+] required for a half-maximum effect on attenuating contractions, at 85.9 (6.2) mm, and developing contracture, at 59.1 (14.3) mm, were significantly different. The time constants of changes to nerve-mediated contractions and carbachol contracture were also significantly different, at 147 (5) vs 1207 (386) s, respectively. These differences suggest that separate mechanisms influence nerve-mediated contraction and contracture in low-Na+ solutions. Exposure to the cardiac glycoside strophanthidin produced a similar effect to low-Na+ solutions for carbachol contracture. Low-Na+ solutions had no significant effect on contractures induced by high extracellular [K+]. CONCLUSION Reducing the transmembrane [Na+] difference increases intracellular [Ca2+]. This increase is largely accommodated in intracellular stores, that can be released by exogenous carbachol. The results are consistent with the presence of a functional Na+-Ca2+ exchanger in the surface membrane. The lack of effect of low-Na+ solutions on contractures evoked by membrane depolarization is consistent with this conclusion. The reduction of the nerve-mediated contraction by low-Na+ solution might result from blockade of the nerve action potential.  相似文献   
90.
The effect of a semisynthetic cardiac glycoside, Actinogen (Ay22241), on Na+ + K+ - ATPase was studied. Ay22241 was found to be as an effective inhibitor of the enzyme as ouabain, Ay22241 inhibition was a time dependent process and was completely reversible. While ouabain inhibition was also time dependent, it was only partially reversible. This reversibility with Ay22241 should make it a useful tool in studying the mode of action of cardiac glycosides.  相似文献   
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