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1.
Two new xanthone glycosides,polygalaxanthone IV and V were isolated from the roots of Polygala tenuifolia Willd. Their structures were established as 6-O-[α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranosyl]-1-hydroxy-3,7-dimethoxyxanthone(polygalaxanthone IV), and 6-O-[α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranosyl]-1,3-dihydroxyl-7-methoxyxanthone (polyga-laxanthone V),respectively, on the basis of chemical and spectral evidence.  相似文献   
2.
黄花倒水莲与六月雪中6种金属元素的测定   总被引:5,自引:0,他引:5  
本文采用火焰原子吸收光谱法对中草药黄花倒水莲、六月雪中茎部的Ca、Zn、Mn、Mg、Fe、Cu的含量进行了测定,方法简单、精密度好,回收率在93%—100%之间,结果令人满意。  相似文献   
3.
Eighteen different triterpene saponins isolated from Polygala tenuifolia were investigated by electrospray ionization ion trap multiple-stage mass spectrometry (ESI-ITMS(n)) in positive and negative ion modes. MS(1)-MS(3)/MS(4) spectra of the both modes were analyzed, and they all gave fragments in line and shared common fragmentation patterns. Key fragments from MS(n) spectra of both the modes and their proposed fragmentation pathways were constructed with examples illustrated for the formation of characteristic fragments in the saponins. Two special fragmentation patterns were proposed: (1) the formation of fragments by cleavage of CH(2)O from Delta(12)-14alpha-CH(2)OH of the oleanene-type saponin aglycone in both positive and negative MS(n) (n > or = 2) modes; (2) the occurrence of fragments by cleavage of CO(2) and 3-glucose as the characteristic structure feature of 23-COOH at the oleanene-type saponin aglycones coupled with 3-Glc substitutes in the negative MS(n) (n > or = 2) modes. Peak intensities in MS(n) spectra were also correlated with structural features and fragmentation preferences of the investigated saponins, which are discussed in detail. In general, fragments formed predominantly by cleavages of glycosidic bonds in the positive mode, while selective cleavages of acyl bonds preceded that of glycosidic bonds in negative MS(n) (n > or = 2) mode, both of which could well be applied to the structural analysis of these saponins. Interpretation of MS(n) spectra presented here provided diagnostic key fragment ions important for the structural elucidation of saponins in P.tenuifolia.  相似文献   
4.
《Analytical letters》2012,45(4):317-322
Abstract

A novel and convenient method for analyzing a minute amount of volatile components in natural samples was devised. Volatile compounds were absorbed into synthetic triglycerides, triolein and tripalmitin then analyzed by chromatography. The authors entitle this method “Enfleurage Chromatography” depending on a classic method “Enfleurage” for perfume preparation. By this method, methyl salicylate from the root of Filipendula multijuga, F. kamtschatica (Rosaceae) and Polygala senega (Polygalaceae) was detected. Besides, salicylaldehyde was identified in F. kamtshatica.  相似文献   
5.
黄花倒水莲皂甙Reinioside C在大鼠体内代谢产物的鉴定   总被引:3,自引:0,他引:3  
为了探讨五环三萜皂甙ReiniosideC在大鼠体内代谢产物的结构,单剂量口服ReiniosideC,5h后放血处死,用制备型高效液相色谱方法对血液和各脏器进行提取分离,从大肠内容物和粪中,分离得到了7种代谢产物.用FAB-MS,1H NMR和13C NMR方法鉴定了它们的结构.  相似文献   
6.
Introduction Xanthonesaresecondarymetabolitescommonly occurringinafewhigherplantfamilies,fungiandli chen.Theirhightaxonomicvalueinsuchfamiliesand theirpharmacologicalproperties,includinginvitrocy totoxicity,invivoantitumouractivity,antifungal,anti bacteri…  相似文献   
7.
<正>Two new oleanane-type saponins,crotalarioside A(1) and crotalarioside B(2),were isolated from the roots of Polygala crotalarioides.Their structures were elucidated on the basis of spectroscopic and chemical evidence.  相似文献   
8.
A new benzophenone C-glycoside from Polygala telephioides Willd   总被引:1,自引:0,他引:1  
<正>A new benzophenone C-glucoside,3'-C-[4-O-(5-hydroxyferuloyl)-β-D-glucopyranosyl]-2′,4′,6′-trihydroxy-3,4-dimethoxy-benzophenone, named telephenone D,was isolated from the whole plants of Polygala telephioides,and its structure was determined by analysis of spectroscopic data.  相似文献   
9.
A rapid and highly selective liquid chromatography–tandem mass spectrometric (LC‐MS/MS) method for determination of polygalasaponin F (PF) in rat plasma was developed and validated. The chromatographic separation was achieved on a reverse‐phase Zorbax SB‐C18 column (150 × 4.6 mm, 5 µm), using 2 mm ammonium acetate (pH adjusted to 6.0 with acetic acid) and acetonitrile (25:75, v/v) as a mobile phase at 30 °C. MS/MS detection was performed using an electrospray ionization operating in positive ion multiple reaction monitoring mode by monitoring the ion transitions from m/z 1091.5 → 471.2 (PF) and m/z 700.4 → 235.4 (internal standard), respectively. The calibration curve showed a good linearity in the concentration range 0.0544–13.6 µg/mL, with a limit of quantification of 0.0544 µg/mL. The intra‐ and inter‐day precisions were <9.7% in rat plasma. The method was validated as per US Food and Drug Administration guidelines and successfully applied to pharmacokinetic study of PF in rats. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
10.
Arillatanosides A–C are three triterpenoid saponins from Polygala arillata Buch–Ham that have been reported previously, but with partially incorrect structures. Further investigation of their NMR data led to the conclusion that the terminal α‐L ‐arabinopyranosyl unit originally proposed for Arillatanosides A–C ( I – III ) is actually a β‐D ‐xylopyranosyl unit. Thus, the correct structures of Arillatanosides A–C are represented by 1 – 3 . Complete NMR assignments of Arillatanosides A–C ( 1 – 3 ) and the related polygalasaponin XXXV ( 4 ) were achieved using modern 2D NMR techniques, such as DQF H–H COSY, HMQC, HMBC, TOCSY, 2D HMQC–TOCSY. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
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