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1.
Identification of metabolites of rupestonic acid in rat urine by liquid chromatography combined with electrospray ionization quadrupole time‐of‐flight tandem mass spectrometry 下载免费PDF全文
Dongyu Gu Yi Yang Qibin Chen Madina Habasi Jiangyu Zhao Haji Akber Aisa 《Biomedical chromatography : BMC》2015,29(4):595-603
Rupestonic acid, a potential anti‐influenza agent, is an important and characteristic compound in Artemisia rupestris L., a well‐known traditional Uighur medicine for the treatment of colds. In the present study, high‐performance liquid chromatography combined with electrospray ionization quadrupole time‐of‐flight tandem mass spectrometry was used to detect and identify the metabolites in rat urine after oral administration of rupestonic acid. A total of 10 metabolites were identified or partially characterized. The structure elucidations of the metabolites were performed by comparing the changes in accurate molecular masses and fragment ions with those of the parent compound. The results showed that the main metabolites of rupestonic acid in rat urine were formed by oxidation, hydrogenation and glucuronidation. A metabolism pathway was proposed for the first time based on the characterized structures. This metabolism study can provide essential information for drug discovery, design and clinical application of rupestonic acid. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
2.
A rapid method had been used for comparative study on Artemisia halodendron Turcz. and its two related plants by gas phase-mass spectrometry (GC-MS). The comparison of the volatile oils obtained in three plants by GC-MS were similar in 20 compositions. However, n-Hexadecanoic acid (10.40%), Biphenyl (7.867%) and 9,12-Octadecadienoic acid (7.25%) were the predominant in the volatile oils of A. halodendron Turcz., whereas these constituents did not exist in the other two plants. And the study investigated the effect of three plants against CCl4-induced hepatotoxicity in mice. 70% ethanol extracts of A. halodendron Turcz. showed weaker protective effect than the other two plants. It suggested that they provide a basis for the identification of the A. halodendron Turcz. from the other two plants and the ethanol extract from three plants exerted a protecting effect against hepatotoxicity. 相似文献
3.
E. M. Suleimenov F. M. Smagulova O. V. Morozova V. A. Raldugin I. Yu. Bagryanskaya Yu. V. Gatilov V. I. Yamovoi S. M. Adekenov 《Chemistry of Natural Compounds》2005,41(6):689-691
The five known lactones matricarin, austricin, canin, and achillin guaianolides and argolide germacranolide and the two flavonoids
eupatilin and its 7-O-methyl ester were isolated for the first time from the aerial part of Artemisia albida Willd. The structure of eupatilin was confirmed by an x-ray structure analysis.
__________
Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 568–570, November–December, 2005. 相似文献
4.
Otmar Hofer Walter Weissensteiner Michael Widhlam 《Monatshefte für Chemie / Chemical Monthly》1983,114(12):1399-1411
The absolute stereochemistry of 14 naturally occurring sesquiterpenecoumarin ethers is discussed. In 13 cases the coumarin moiety is isofraxidin (7-hydroxy-6,8-dimethoxycoumarin), in one case scopoletin (7-hydroxy-6-methoxycoumarin). The sesquiterpene moieties belong either to the bicyclic drimenole series or to its consecutive products (methyl migration, ring opening). The CD spectra of all compounds are given. The assignments of the absolute configurations are based on the method ofHoreau, chemical correlation by degradation reactions, extensive comparison of CD data, and biogenetic considerations.
Absolute Konfigurationen und Circulardichroismus von Sesquiterpen-Cumarin-Ethern
Zusammenfassung Es wird die absolute Stereochemie von 14 natürlich vorkommenden Sesquiterpen-Cumarin-Ethern diskutiert. In 13 Fällen wird die Cumarineinheit von Isofraxidin (7-Hydroxy-6,8-dimethoxycumarin) repräsentiert, in einem Fall von Scopoletin (7-Hydroxy-6-methoxycumarin). Der Sesquiterpenteil ist entweder von Drimenol oder Folgeprodukten (Methylgruppenwanderung, Ringöffnung) abgeleitet. Die CD-Spektren aller Verbindungen sind angegeben. Die Zuordnung der absoluten Konfigurationen basiert auf der Methode vonHoreau, chemischer Korrelation über Abbaureaktionen, Vergleich der CD-Spektren und biogenetischen Überlegungen.相似文献
5.
6.
A rapid and simple RP-TLC method for simultaneous quantification of pharmacologically important sesquiterpene artemisinin (AM) together with its precursors arteannuin-B (AB) and artemisinic acid (AA) in the inflorescence part of Artemisia annua plant has been developed. The RP-TLC of sesquiterpenes was performed on RP-18 F254 S thin-layer chromatographic plates by developing in mobile phase, containing 0.2% TFA in water/ACN (35:65, v/v). The densitometric determination of AM, AB and AA was carried out after derivatization with anisaldehyde reagent at 426 nm in absorption-reflectance mode. 相似文献
7.
Eupatilin (5,7-dihydroxy-3',4',6-trimethoxy flavone) is an active ingredient of an ethanol extract of Artemisia asiatica (DA-9601) that is used in the treatment of gastritis. In vitro and in vivo metabolism of eupatilin in the rats has been studied by LC-electrospray mass spectrometry. Rat liver microsomal incubation of eupatilin in the presence of NADPH and UDPGA resulted in the formation of four metabolites (M1-M4). M1, M2, M3 and M4 were tentatively identified as 3'- or 4'-O-demethyl-eupatilin glucuronide, eupatilin glucuronide, 6-O-demethyleupatilin and 3'- or 4'-O-demethyl-eupatilin, respectively. Those metabolites from in vitro study were also characterized in bile, plasma or urine samples after an intravenous administration of eupatilin to rats. In rat bile, plasma and urine samples, eupatilin glucuronide (M2) was a major metabolite, whereas M3, M4 and M4 glucuronide (M1) were the minor metabolites. 相似文献
8.
N. A. Talzhanov D. T. Sadyrbekov F. M. Smagulova R. M. Mukanov V. A. Raldugin M. M. Shakirov A. V. Tkachev G. A. Atazhanova B. I. Tuleuov S. M. Adekenov 《Chemistry of Natural Compounds》2005,41(2):178-181
Chemical components from the aerial part of the Kazakhstan population of Artemisia pontica, from which the rarely encountered flavonoids 7-O-methyl- and 4′,7-di-O-methyl-esters of apigenin were isolated for the first time, were identified. The complete chemical composition of the essential oil was established using GC-MS.__________Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 143–145, March–April, 2005. 相似文献
9.
G. A. Atazhanova A. T. Kulyyasov A. D. Dembitskii V. A. Raldugin M. M. Shakirov I. Yu. Bagryanskaya Yu. V. Gatilov S. M. Adekenov G. A. Tolstikov 《Chemistry of Natural Compounds》2000,36(2):152-155
The oxime of artemisia ketone is smoothly converted to the pyrazole derivative by sodium nitrite and acetic acid in CHCl3. The structure of the pyrazole was found by x-ray structural analysis. The PMR and13C NMR spectra were interpreted using two-dimensional1H–13C NMR (COSY, COLOC).Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 121–123, March–April, 2000. 相似文献
10.
Asish K Bhattacharya Mahesh PalDharam C Jain Bhawani S JoshiRaja Roy Urszula RychlewskaRam P Sharma 《Tetrahedron》2003,59(16):2871-2876
Absolute stereochemistry of dihydroarteannuin B 5 obtained by the reduction of arteannuin B 3 with Ni2B, NaBH4 or CdCl2-Mg-MeOH-H2O has been established by 2D NMR and single crystal X-ray diffraction studies. Some experiments aimed at the synthesis of dihydrodeoxyarteannuin B [C-4, 5 double bond isomer of 11] are also discussed. 相似文献