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91.
Yan‐Ping Zou Chang‐Heng Tan Bao‐De Wang Shan‐Hao Jiang Da‐Yuan Zhu 《Helvetica chimica acta》2007,90(10):1940-1945
Four new flavonoid glycosides, 3‐O‐[α‐L ‐arabinopyranosyl‐(1→2)‐β‐D ‐galactopyranosyl]‐7‐O‐β‐D ‐glucopyranosylkaempferol ( 1 ), 3‐O‐(α‐L ‐arabinopyranosyl‐(1→2)‐{4‐O‐[(E)‐caffeoyl]‐β‐D ‐galactopyranosyl})‐7‐O‐β‐D ‐glucopyranosylquercetin ( 2 ), 3‐O‐{2‐O‐[(E)‐caffeoyl]‐α‐L ‐arabinopyranosyl‐(1→2)‐β‐D ‐galactopyranosyl}‐7‐O‐β‐D ‐glucopyranosylkaemperfol ( 3 ), and 3‐O‐{2‐O‐[(E)‐caffeoyl]‐α‐L ‐arabinopyranosyl‐(1→2)‐β‐D ‐galactopyranosyl}kaempferol ( 4 ), together with two known compounds were isolated from the aerial parts of Ranunculus chinensis Bge . The structures of the new glycosides were determined on the basis of spectroscopic analysis, including 1D‐ and 2D‐NMR, and ESI‐MS techniques, and chemical methods. 相似文献
92.
By means of spectroscopic analysis, X-ray crystallography and chemical correlation the heartwood of Taiwan hemlock was found to contain compounds of sterols, carboxylic acids, 13-epimanool, o methoxyphenolics, coniferaldehyde, benzofuranoid neolignan, α-conidendrin, tsugacetal, isolariciresinol, secoisolariciresinol, matairesinol, hydroxymatairesinol and oxomatairesinol. Among them (+)-tsugacetal is a novel lignan acetal having an α-conidendrin related structure with the acetal methoxy group at the β-position. 相似文献
93.
Jia-Ning Gao Xin Li Jun Liang Hai-Xue Kuang Yong-Gang Xia 《Journal of separation science》2023,46(8):2200797
Due to green and environment-friendly characteristics, ultra-high-performance supercritical fluid chromatography has been widely used in analytical fields in recent years, but until now few reports are available for monosaccharide compositional analysis of macromolecule polysaccharides. In this study, an ultra-high-performance supercritical fluid chromatography technology with an unusual binary modifier is used to determine the monosaccharide compositions of natural polysaccharides. Each carbohydrate herein is simultaneously labeled as 1-pheny-3-methyl-5-pyrazolone and acetyl-derivative via pre-column derivatizations aiming to increase UV absorption sensitivity and decrease water solubility. Ten common monosaccharides are fully separated and detected on ultra-high-performance supercritical fluid chromatography combined with a photo-diode array detector by systematic optimization of multiple relevant parameters, for example, column stationary phases, organic modifiers, additives, flow rates, and so on. Compared with carbon dioxide as a mobile phase, the addition of a binary modifier increases the resolution of analytes. Additionally, this method has the advantages of small consumption of organic solvent, safety, and being environmental-friendly. It has been successfully applied for full monosaccharide compositional analysis of heteropolysaccharides from Schisandra chinensis fruits. To sum up, a new alternative approach is provided for monosaccharide compositional analysis of natural polysaccharides. 相似文献
94.
Hao G Zhao W Lei Y Yang Y Zhi-Hong Y Nai-Li W Guang-Xiong Z Wen-Cai Y Xin-Sheng Y 《Magnetic resonance in chemistry : MRC》2008,46(7):630-637
Eleven triterpenoid saponins (1-11) were isolated from Stauntonia chinensis DC. (Lardizabalaceae), including five new compounds, yemuoside YM(21-25) (1-3, 6, 7) structures of which were elucidated by chemical methods and a combination of MS, 1D- and 2D- NMR experiments including DEPT, (1)H--(1)H COSY, HSQC, HMBC, TOCSY, and NOESY as 3-O-alpha-L-arabinopyranosyl-(1 --> 3)-[alpha-L-rhamnopyranosyl-(1 --> 2)-]alpha-L-arabinopyranosyl-akebonicacid-28-O-alpha-L-rhamnopyranosyl-(1 --> 4)-beta-D-glucopyranosyl-(1 --> 6)-beta-D-glucopyranosyl ester (1), 3-O-beta-D-xylopyranosyl-(1 --> 3)-alpha-L-rhamnopyranosyl-(1 --> 2)-alpha-L-arabinopyranosyl-akebonic acid-28-O-alpha-L-rhamnopyranosyl-(1 --> 4)-beta-D-glucopyranosyl-(1 --> 6)-beta-D-glucopyranosyl ester (2), 3-O-beta-D-glucopyranosyl-(1 --> 3)-alpha-L-arabinopyranosyl-akebonic acid-28-O-alpha-L-rhamnopyranosyl-(1 --> 4)-beta-D-glucopyranosyl-(1 --> 6)-beta-D-glucopyranosyl ester (3), 3-O-alpha-L-arabinopyranosyl-(1 --> 3)-[alpha-L-rhamnopyranosyl-(1 --> 2)-]alpha-L-arabinopyranosyl-akebonic acid-28-O-beta-D-glucopyranosyl-(1 --> 6)-beta-D-glucopyranosyl ester (6), 3-O-alpha-L-arabinopyranosyl-(1 --> 3)-[alpha-L-arabinopyranosyl-(1 --> 2)-]alpha-L-arabinopyranosyl-akebonic acid-28-O-beta-D-glucopyranosyl-(1 --> 6)-beta-D-glucopyranosyl ester (7). 相似文献
95.
Feng WEI* Ling Yun MA Yan LIU Rui Chao LIN Division of Chinese Materia Medica Natural Products National Institute for the Control of Pharmaceutical & Biological Products State Drug Administration Beijing 《中国化学快报》2002,13(1)
Aesculus chinensis is a traditional chinese medicinal plant widely distributed in China, which has been used to treat stomach disease. From recent research its seeds contain many flavonoids and proanthocyanidin A2, which have potential venotonic and vasoprotective action and powerful antioxidant activity. In this paper, we report the isolation and the structure elucidation of a new flavonol oligosacchride. Bioassay results showed that the compound exhibited an antivirus activity. … 相似文献
96.
Cell extraction combined with off‐line HPLC for screening active compounds from Coptis chinensis
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Cheng Tang Xiao‐Dan Wu Ya‐Ming Yu Hongquan Duan Jing Zhou Liang Xu 《Biomedical chromatography : BMC》2016,30(4):658-662
Cell membrane chromatography is a useful tool for screening active compounds from natural products. As the reason of separation mechanism, traditional cell membrane chromatography could not be used for screening the active compounds absorbed through the cell membrane and influencing the cell signal transduction pathway. In this work, we establish a new method named cell extraction combined with off‐line HPLC for screening the compounds penetrating the cell membrane. This is the first time 3 T3‐L1 adipocyte culture has been combined with HPLC technology. Compared with other cell membrane chromatography methods, there is good resolution and no further analysis by other chromatographic steps is required. On co‐incubating crude extracts of Coptis chinensis with cells and analyzing the compounds extracted by the cells, active compounds such as berberine were detected. Glucose consumption tests showed that berberine could increase glucose consumption by insulin‐resistant 3 T3‐L1 adipocytes. The levels of intracellular berberine correlated with its activity. The results indicate that the developed method could be an alternative method for screening active compounds from natural products. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
97.
Shi-Ji Xiao Da-Le Guo Mao-Sheng Zhang Shu-Ling Peng Fang Chen Yan Zhou Li-Sheng Ding 《中国化学快报》2016,27(7):1064-1066
Two novel 2,5-diphenyl oxazole derivatives, named gymnothecaoxazoles A (1) and B (2), were isolated from the whole parts of endemic medicinal plant of Gymnotheca chinensis (Saururaceae). The structures of the new compounds were elucidated by extensive NMR and MS data, and the structure of compound 1 was further confirmed by X-ray crystal diffraction analysis. 相似文献
98.
Comparative pharmacokinetic profiles of five poorly soluble pulchinenosides in different formulations from Pulsatilla chinensis saponins extracts for enhanced bioavailability
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Jun Huang Yali Liu Xiang Li Yonggui Song Wei Li Kuangyi Liu Dan Su Yulin Feng Shilin Yang 《Biomedical chromatography : BMC》2015,29(12):1885-1892
Pulsatilla chinensis, a traditional Chinese medicine (TCM), has been used for treating amoebic diseases, vaginal trichomoniasis and bacterial infections over a long history. Now growing attention has been attracted to its antitumor activities. The purpose of this work was to compare the pharmacokinetic profiles of pulchinenosides in different formulations and to improve their oral bioavailability. Extracts of P. chinensis saponins were prepared for PRS‐Na (salt forming), PRS‐HPβCD (hydroxypropyl‐β‐cyclodextrin inclusion complex), PRS‐O/W (oil‐in‐water emulsion) and PRS‐silica (micronization), respectively. A simpler and more durable LC‐MS/MS method was developed in this study for quantitative analysis of pulsatilla sapoin D, B7, B10, B11 and sapoin PD simultaneously. The four formulations enhanced saponins oral bioavailability to varying degrees, as PRS‐HPβCD > PRS‐silica > PRS‐O/W > PRS‐Na, which indicated that water‐soluble preparations can obviously improve the solubility of saponins, and are helpful to increase bioavailability. In particular, hydroxypropyl‐β‐cyclodextrin inclusion complex was the most effective way to promote absorption of saponins, raising the F values (bioavailability) >20 times. Therefore, P. chinensis saponin molecules can be slowly released by emulsion and micronization, which can avoid the enormous Cmax appearing in HPβCD, considering the pharmacokinetics profiles. However, appropriate pharmacokinetic parameters were observed in PRS‐Na, although the F value was minimum among the four preparations. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
99.
Two new isomeric compounds of rare acyclic C_(13)-norisoprenoids,along with two known lignans sauchinone and licarin A,were isolated from the herb of Saururus chinensis(Lour.) Baill.Their structures were elucidated on the basis of spectral analysis. 相似文献
100.
A new bidesmoside triterpenoid saponin,named stauntoside C1(1) has been isolated from Stauntonia chinensis.Its structure was established by means of spectral and chemical methods. 相似文献