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11.
The sesquiterpene lactones xanthanodiene, 4-epi-xanthanol, 4-epi-isoxanthanol, and 4-epi-xanthinin, as well as the xanthanolide derivative 4-oxo-bedfordia acid were isolated from the chloroform extracts of roots and flowers of Xanthium cavanillesii Schouw. The identities of these compounds were corroborated through comparison of their spectroscopic data, including IR, MS, and 1H and 13C NMR assignments, with literature reports. In addition, the structural characterization of 4-oxo-bedfordia acid was revisited and a comprehensive spectroscopic study of the compound is presented. This is to our knowledge the first phytochemical investigation of the roots of X. cavanillesii, and of flowers in the whole Xanthium genus. 相似文献
12.
13.
Ting Yuan Cuiyun Zhang Chongyue Qiu Guiyang Xia Fei Wang Bin Lin 《Natural product research》2018,32(16):1887-1892
A new bisabolane-type sesquiterpenoid, turmerone Q (1), along with six known compounds (2–7), were isolated from the rhizomes of Curcuma longa L. The structural elucidation of the new compound was conducted using 1H NMR, 13C NMR, HSQC, HMBC and NOESY spectroscopic analyses. The absolute configuration of 1 was elucidated by comparison of the experimental and calculated ECD spectra. The anti-inflammatory effects of 1–7 were evaluated through lipopolysaccharide-induced nitric oxide (NO) production in RAW 264.7 macrophages assays, and compounds 6 and 7 showed potent inhibitory activity against NO production. 相似文献
14.
Zi‐Ming Feng Shuang Song Peng‐Fei Xia Jian‐Shuang Jiang Pei‐Cheng Zhang 《Helvetica chimica acta》2009,92(9):1823-1828
Phytochemical investigation of the flowers of Chrysanthemum indicum L. led to the isolation of three new sesquiterpenoids, indicumolide A ( 1 ), indicumolide B ( 2 ), and indicumolide C ( 3 ). Their structures were elucidated by various spectroscopic methods. 相似文献
15.
Two new sesquiterpenes named liguducin-A ( 1 ) and -B ( 4 ) were isolated from a Chinese medicinal plant, the dried roots of Ligularia duciformis, together with four known sesquiterpenes, 4α, 10β-dihydroxy-1β,5α-H-guai-6-ene ( 2 ), 4α-hydroxy-1β,5α,11α-H-guai-9-en-12,8α-olide ( 3 ), 1β-hydroxyeudesm-4,11-dien-3-one ( 5 ) and 1β,6α-dihydroxyeudesm-4(15)-ene ( 6 ). On the basis of the spectral evidence, their structures were determined. 相似文献
16.
Data on the partial synthesis of enantiomerically pure sesquiterpenoids of the drimane group, including valuable biologically
active natural compounds, from accessible labdane diterpenoids are surveyed.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 896–913, May 1997. 相似文献
17.
A. T. Kulyyasov I. Yu. Bagryanskaya Yu. V. Gatilov M. M. Shakirov V. A. Raldugin S. M. Adekenov T. S. Seitembetov 《Russian Chemical Bulletin》1998,47(7):1390-1394
A new sesquiterpenoid lactone was isolated from terrestrial parts ofArtemisia subchrysolepis Filat. and studied by X-ray diffraction analysis and CD spectroscopy. This compound was called subchrysine and identified
as (1R,3S,4E,6R,7S)-3-acetoxy-1-hydroxygernmacra-4,10(14), 11(13)-trien-12,6-olide. Pronounced temperature dependence of the1H and13C NMR spectra of subchrysine was observed. The results of conformational analysis of subchrysine by quantum-chemical (PM3)
and molecular mechanics (MMX) methods are also presented.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1429–1433, July, 1998. 相似文献
18.
A. G. Berdin S. M. Adekenov V. A. Raldugin M. M. Shakirov A. G. Druganov A. T. Kulyyasov G. A. Tolstikov 《Russian Chemical Bulletin》1999,48(10):1987-1991
Two new crystalline guaianolides,viz., rhaposerine and rhaserolide, were isolated from an ethanolic extract of the above-ground part of the plantRhaponticum serratuloides by column chromatography along with sesquiterpene lactones,viz., centaurepensin and acroptilin, which have been found in other plants. The chemical structures of the title lactones were
established by1H and13C NMR spectroscopy and 2D1H−1H (COSY) and13C−1H (COSY and COLOC) NMR spectroscopy.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2010–2014, October, 1999. 相似文献
19.
20.
Superacid cyclization was demonstrated for the first time to be successful in those ionic liquids with functional groups that
are stable in the reaction medium using aliphatic sesquiterpene derivatives as examples.
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Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 354–356, July–August, 2006. 相似文献