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11.
The known hederagenin 3-O-β-D-glucopyranosyl-(1→4)-O-β-D-xylopyranosyl-(1→ 3)-O-α-L-rhamnopyranosyl-(1→2)-O-α-L-arabinopyranoside (sapindoside C) and its 28-O-α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl and 28-O-α-L-rhamnopyranosyl-(1→4)-O-6-O-acetyl-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl esters, new triterpene glycosides, were isolated from leaves of Kalopanax septemlobum var. maximowiczii introduced to Crimea. The structures of these compounds were established using chemical methods and two-dimensional NMR spectroscopy.__________Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 260–262, May–June, 2005.  相似文献   
12.
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   
13.
以常春藤皂苷元为原料,对其3,23-羟基和28-羧基进行乙酰化、醚化、苯甲酰化及酯化等反应合成了8个常春藤皂苷元衍生物(2~9),其中6个未见文献报道,其结构经1H NMR, 13C NMR, IR和MS表征。采用MTT法测定了2~9的体外抗HBV活性。结果表明:3~9随浓度增大,对细胞活力的抑制率明显增加,特别是7和9抑制率最明显,用药浓度为1×10-6mol·L-1时,抑制率均为9.46±0.47%。对2~9抑制Hep G2.2.15细胞表达表面抗原(HBs Ag)进行了测试。结果表明:2~9对HBs Ag的分泌表达有一定的抑制作用。  相似文献   
14.
The structures of seven triterpene glycosides (1–7), of which the 23-O-acetyl, 28-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl ester of hederagenin 3-O-β-D-glucopyranosyl-(1→3)-O-α-L-rhamnopyranosyl-(1→2)-O-α-L-arabinopyranoside (2) was new, from the flower buds of Lonicera macranthoides were established using chemical and NMR spectroscopic methods. Published in Khimiya Prirodnykh Soedinenii, No. 1, pp. 32–34, January–February, 2008.  相似文献   
15.
A nonasaccharide saponin, new hederagenin saponin, had been isolated from the bark ofKalopanax septemlobus (Thunb.) Koidz., and its structure was elucidated by HRESI-MS, NMR experi-ments and chemical analyses as 3-O-β-D-xylopyranosyl-(1→4)-13-D-xylopyranosyl-(1→3)-α-L-rhamno-pyranosyl-(1→2)-α-L-arabinopyranosyl hederagenin 28-O-β-D-xylopyranosyl-(1→3)-β-D-xylopyra-nosyl-(1→2)-[α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranosyl-(1→6)]-β-D-glucopyranoside.  相似文献   
16.
A rapid and sensitive liquid chromatography tandem mass spectrometry (LC–MS/MS) was developed and validated for simultaneous quantification of oleanolic acid and hederagenin in rat plasma. After the two analytes were extracted with liquid–liquid extraction, chromatographic separation was performed on a C18 column with acetonitrile and water (85:15, v /v) as mobile phase at a flow rate of 0.4 mL/min. Calibration curves exhibited good linearity (r > 0.995) over the ranges of 0.41–82.0 ng/mL for oleanolic acid and 0.32–64.0 ng/mL for hederagenin, respectively. The lower limit of quantifications (LLOQs) in plasma were 0.41 ng/mL for oleanolic acid and 0.32 ng/mL for hederagenin. The established LLOQs were within the concentration needed for the assay in plasma, which met the requirements to evaluate their pharmacokinetics of oleanolic acid and hederagenin. This developed assay was successfully applied in the pharmacokinetic study of oleanolic acid and hederagenin in rats after oral administration of Rhizoma Clematidis extract.  相似文献   
17.
The new caffeylated triterpene glycosides hederagenin 3-O-(6-O-caffeyl-β-D-glucopyranosyl)-(1→4)-O-β-D-xylopyranosyl-(1→3)-O-α-L-rhamnopyranosyl-(1→2)-O-β-L-arabinopyranoside and its 28-O-α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl and 28-O-α-L-rhamnopyranosyl-(1→4)-O-6-O-acetyl-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl esters were isolated from leaves of Kalopanax septemlobum var. maximowiczii introduced in Crimea. The structures of these compounds were established using chemical methods and NMR spectroscopy.__________Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 263–267, May–June, 2005.  相似文献   
18.
Thirteen known glycosides of hederagenin and oleanolic acid and the three new triterpene glycosides of oleanolic acid-28-O-α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl ester 3-O-β-D-glucopyranosyl-(1→4)-O-β-D-xylopyranosyl-(1→ 3)-O-α-L-rhamnopyranosyl-(1→2)-O-α-L-arabinopyranoside of oleanolic acid and the 28-O-α-L-rhamnopyranosyl-(1→4)-O-6-O-acetyl-β-D-glucopyranosyl-(1→ 6)-O-β-D-glucopyranosyl esters 3-O-β-D-xylopyranosyl-(1→3)-O-α-L-rhamnopyranosyl-(1→2)-O-α-L-arabinopyranoside of oleanolic acid and 3-O-β-D-glucopyranosyl-(1→4)-O-β-Dxylopyranosyl-(1→3)-O-α-L-rhamnopyranosyl-(1→ 2)-O-α-L-arabinopyranoside of oleanolic acid were isolated from leaves of Kalopanax septemlobum var. typicum introduced to Crimea. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 40–43, January–February, 2006.  相似文献   
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