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101.
Dantonic pill, consisting of Salviae miltiorrhize , Panax notoginseng and Borneol , is a widely used compound Chinese medicine for preventing and treating ischemic cardiovascular diseases in China. In the present study, an original and sensitive method for simultaneous determination of tanshinol (i.e. danshensu), protocatechuic aldehyde, protocatechuic acid, notoginsenoside R1, ginsenoside Rg1 and Rb1 in rat plasma by liquid chromatography–tandem mass spectrometry operated in positive/negative ion switching mode was established and validated. The lower limits of quantification for tanshinol, protocatechuic aldehyde, protocatechuic acid, notoginsenoside R1, ginsenoside Rg1 and Rb1 were 5, 0.5, 1, 0.5, 0.5 and 2 ng/mL, respectively. All of the calibration curves showed good linearity over the investigated concentration range (r > 0.99). Validation results demonstrated that the above compounds were accurately, precisely and robustly quantified in rat plasma. The method was successfully applied to characterize the pharmacokinetic profiles of all six compounds in rats following a single oral administration of Dantonic pill.  相似文献   
102.
卷丹皂苷A和甾体皂苷的NMR特征   总被引:5,自引:0,他引:5  
应用2D NMR技术:1H-1H COSY、HMQC、HMBC全归属新化合物卷丹皂苷A和已知化合物麦冬皂苷D′ 的碳和氢质子信号,总结薯蓣皂苷元类型甾体皂苷的NMR特征,为该类型化合物的结构鉴定提供光谱学依据.  相似文献   
103.
A new HPLC coupled with evaporative light scattering detection method was established for the simultaneous determination of seven triterpenoids and triterpenoid saponins in Folium Ilicis Purpureae traditional Chinese medicinal herb derived from the leaf of Ilex purpurea, namely, 3-omicron-beta-D-glucopyranosyl (1-->2)-beta-D-[6-omicron-methyl-glucuronopyranosyl]-28-omicron-beta-D-glucopyranosyl oleanolic acid (SQ-1), pedunculoside (SQ-2), 23-hydroxytormentic acid 28-omicron-beta-D-glucopyranoside (SQ-3), 23-hydroxytormentic acid (SQ-4), rutundic acid (SQ-5), ilexoside B (SQ-6), and ursolic acid (SQ-7). The optimal chromatographic conditions were achieved on a C18 column with a linear gradient elution of mobile phase A: deionized water-isopropyl alcohol-THF-acetic acid (90:10:6:1, v/v) and B: methanol-isopropyl alcohol-THF-acetic acid (90:10:6:1, v/v) at the flow rate of 1.0 mL/min; temperature for drift tube was set at 98degreesC and nitrogen flow rate was 2.8 L/min. All calibration curves of the seven compounds showed good linear regression (r2 > 0.995) within test ranges. The developed method has good repeatability for quantitation of all analytes interested with overall intraday and interday variation of less than 4.1%. The LOD (S/N = 3) and LOQ (S/N = 10) were less than 0.13 and 0.26 microg/mL, respectively, for all analytes. The established method was successfully used to evaluate the quality of Folium Ilicis Purpureae samples of different collections.  相似文献   
104.
Complete 1H and 13C spectral assignments are reported for six saponins from the pericarp of Sapindus trifoliatus (Hindi name: Reetha) collected from Madhya Pradesh and Maharashtra, India, using only 1D and 2D NMR methods. The structures of the compounds were elucidated as hederagenin 3-O-(3-O-acetyl-beta-D-xylopyranosyl)-(1-3)-alpha-L-rhamnopyranosyl-(1-2)-alpha-L-ara-binopyranoside, hederagenin 3-O-(4-O-acetyl-beta-D-xylop-yranosyl)-(1-3)-alpha-L-rhamnopyranosyl-(1-2)-alpha-L-arabinop-yranoside, hederagenin 3-O-(3,4-O-diacetyl-beta-D-xylopy-ranosyl)-(1-3)-alpha-L-rhamnopyranosyl-(1-2)-alpha-L-arabinopy-ranoside, hederagenin 3-O-(3,4-O-diacetyl-alpha-L-arabinop-yranosyl)-(1-3)-alpha-L-rhamnopyranosyl-(1-2)-alpha-L-arabinop-yranoside, hederagenin 3-O-(beta-D-xylopyranosyl)-(1-3)-alpha-L-rhamnopyranosyl-(1-2)-alpha-L-arabinopyranoside and he-deragenin 3-O-(alpha-L-arabinopyranosyl)-(1-3)-alpha-L-rhamno-pyranosyl-(1-2)-alpha-L-arabinopyranoside. It is concluded that saponins of this complexity approach the limit of structural complexity, which can be solved by NMR alone, precisely and quickly.  相似文献   
105.
Six new triterpene saponins bearing an oxygen bridge between C-13 and C-28 and with pronounced anti-leishmanial activity were isolated from the methanolic extract of leaves of the Vietnamese medicinal plant Maesa balansae. The structure was established on the basis of detailed NMR (COSY, NOESY, HMQC, HMBC, TOCSY and DEPT) and FAB-MS studies along with chemical degradation. All saponins identified contained the same pentaglycosidic side chain, but a different esterification pattern on the triterpenoid part. Biological evaluation of the individual compounds against visceral leishmaniasis (Leishmania infantum amastigotes) revealed a much better activity in vitro compared to the reference compound Pentostam®, which is currently used as first-line treatment for leishmaniasis.  相似文献   
106.
Two new saponins were isolated from an ethanol extract of the whole plants of Lysimachia davuria. The new saponins were respectively characterized as 3-O-{β-D-glucopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→4)]-α-L-arabinopyranosyl}-3β,28-dihydroxyolean-12-en-30-oic acid-O-[β-D-xylopyranosyl-(1→2)-β-D-glucopyranosyl]-ester (1) and 3-O-{ β-D-glucopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→4)]-α-L-arabinopyranosyl}-3β,28-dihydroxyolean-12-en-30-oic acid-O-β-D-glucopyranosyl-ester (2). Their structures were determined by 1D, 2D NMR and MS techniques. Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 466–468, September–October, 2007.  相似文献   
107.
Six new triterpene glycosides, repensosides A–F ( 1 – 6 , resp.), were isolated from the roots of Gypsophila repens L. Their structures, established by extensive 1D‐ and 2D‐NMR spectroscopic experiments as well as MS analyses, were found to be based on gypsogenic acid (or gypsogenin) as aglycone, with three to nine branched or unbranched sugar moieties.  相似文献   
108.
Several stigamasterol saponins were concisely synthesized.Namely,four monosaccharide(glucopyranose,ga-lactopyranose,xylopyranose,2-acetamido-2-deoxy-a-D-glucopyranose),lactopyranose and chacotriose were cou-pled with 3-OH of stigmasterol.All the compounds were identified by NMR,IR and high resolusion MS.  相似文献   
109.
Licorice is among the most popular herbal medicines and frequently used in traditional medicine, food products, and cosmetics. In China, only Glycyrrhiza uralensis Fisch., Glycyrrhiza inflata Bat. and Glycyrrhiza glabra L. are officially used and are usually processed with honey prior to use. To maintain the quality of commercially available herbal products, a simple, rapid, and reliable ultra high performance liquid chromatography with triple quadrupole mass spectrometry was developed to investigate the major active constituents of commercially available licorice products. Nineteen components were accurately determined, including eight triterpenoid saponins, one triterpene, and ten flavonoids. Subsequently, multivariate statistical analysis methods were employed to further explore and interpret the experimental data. The results indicated that liquiritin apioside may be considered as a candidate index for the quality control of licorice as well as 18β‐glycyrrhizic acid and liquiritin. In addition, both 18β‐glycyrrhizic acid and licorice‐saponin G2 can be used for discrimination between crude and honey‐processed licorice. Furthermore, using 18β‐glycyrrhizic acid and liquiritin as markers, this work revealed that the quality of licorice products may have declined in recent years. This highlights the need for additional effort focused on good agricultural practice during the processing of licorice. In summary, this study provides a valuable reference for the quality assessment of licorice.  相似文献   
110.
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   
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