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21.
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.
__________
Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 354–356, July–August, 2006. 相似文献
22.
Lyakhova E. G. Fedorov S. N. Shubina L. K. Radchenko O. S. Kalinovsky A. I. Dvitrenok P. S. Stonik V. A. 《Russian Chemical Bulletin》2003,52(4):1022-1026
The structures of products obtained by reductive debromination and CF3COOH- and KOH-induced transformations of natural chamigrane-type sesquiterpenoid (6S,10R)-10-bromo-3,11,11-trimethyl-7-methylidenespiro[5,5]undec-2-en-4-one (dactylone) isolated from the sea hare Aplysia dactylomela were analyzed. The absolute configurations of the reaction products were established by CD spectra taking into account the configuration of the starting dactylone. 相似文献
23.
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
24.
Xue Zhou Jie Wang Lifang Sun Anya Xiang Qinglong Shi Haichi Li Dan Zhou Fahuan Ge 《Journal of separation science》2020,43(13):2646-2656
A green and efficient strategy was established and optimized for target‐oriented extraction, enrichment and separation of cadinene sesquiterpenoids from Eupatorium adenophorum Spreng., using the combination of supercritical fluid extraction, molecular distillation, and industrial preparative chromatography for the first time. The extraction conditions of supercritical fluid extraction were initially optimized by orthogonal experimental design. Under the optimum conditions, the contents of 9‐oxo‐10,11‐dehydroageraphorone and 10Hβ‐9‐oxo‐ageraphorone, which were 55.00% and 6.01%, respectively, were much higher than conventional extraction methods. Then, the molecular distillation enrichment method was established and investigated by response surface methodology technology, which showed strong specificity for enriching target compounds and removing impurities from crude extracts. Under the optimum conditions of molecular distillation, total contents of cadinene sesquiterpenoids were increased to 89.19%. Finally, a total of 146 mg of 9‐oxo‐10,11‐dehydroageraphorone and 29 mg of 10Hβ‐9‐oxo‐ageraphorone were easily obtained by industrial preparative chromatography, from 200 mg of distillation fraction, with purities over 99%. The contents of target components were analyzed by HPLC, and structures of them were identified by high‐resolution MS, 1H‐NMR, and 13C‐NMR spectroscopy. These results indicate that it is a simple, effective, and eco‐friendly strategy, which is easily converted into industrial scale. 相似文献
25.
Zhu-Zhen Han Xian-Peng Zu Jin-Xin Wang Hui-Liang Li Bing-Yang Chen Qing-Xin Liu Xian-Qing Hu Zhao-Hui Yan Wei-Dong Zhang 《Tetrahedron》2014
Valeneomerins A–D, two new neomerane-type sesquiterpenoids and two new nor-sesquiterpenoids, were isolated from the roots of Valeriana officinalis var. latifolia. Among them, valeneomerin A (1) was identified as a sesquiterpenoid with an unprecedented 15,3-lactone loop while valeneomerin C (3) and valeneomerin D (4) were determined to be nor-sesquiterpenoids with a new 15-reductive neomerane-type carbon skeleton. Their structures were elucidated by detailed spectroscopic analysis and Cu Kα X-ray crystallography. Compounds 1, 2, and 4 exhibited significant neuroprotective effects against H2O2 induced oxidative stress in SH-SY5Y cells with viability of 49.8, 40.9, and 44.6% each at 50 μM, respectively, in contrast to positive control (catechin, 50 μM) with viability of 32.6%. 相似文献
26.
Sai Jiang Mengyun Wang Zichen Jiang Salman Zafar Qian Xie Yupei Yang Yang Liu Hanwen Yuan Yuqing Jian Wei Wang 《Molecules (Basel, Switzerland)》2021,26(10)
Plants from the Chrysanthemum genus are rich sources of chemical diversity and, in recent years, have been the focus of research on natural products chemistry. Sesquiterpenoids are one of the major classes of chemical constituents reported from this genus. To date, more than 135 sesquiterpenoids have been isolated and identified from the whole genus. These include 26 germacrane-type, 26 eudesmane-type, 64 guaianolide-type, 4 bisabolane-type, and 15 other-type sesquiterpenoids. Pharmacological studies have proven the biological potential of sesquiterpenoids isolated from Chrysanthemum species, reporting anti-inflammatory, antibacterial, antitumor, insecticidal, and antiviral activities for these interesting molecules. In this paper, we provide information on the chemistry and bioactivity of sesquiterpenoids obtained from the Chrysanthemum genus which could be used as the scientific basis for their future development and utilization. 相似文献
27.
《Tetrahedron letters》2003,44(37):7023-7025
Annuionones (1-5), allelopathic agents isolated from Helianthus annus (sunflower), were reported to be ionone-type bisnorsesquiterepenes. However, the proposed structures for annuionones A (1), B (2) and E (5) were thought to be incorrect. Thus, we have tentatively proposed a revised structure (6) for annuionone A based on careful re-analyses of the reported spectral data. The synthesis of (±)-6 was accomplished to prove the structure of natural annuionone A as 6. 相似文献
28.
S. M. Adekenov A. T. Kulyjasov V. A. Raldugin I. Yu. Bagryanskaya Yu. V. Gatilov M. M. Shakirov 《Russian Chemical Bulletin》1998,47(1):169-172
A new germacranolide, ajanolide A, was isolated from aerial parts ofAjania fruticulosa by means of extraction with CHCl3 and adsorption chromatography. This compound was identified as (1(10)E,3S,4Z,6R,7S,11R)-3-acetoxygermacra-1(10),4-dien-12,6-olide ((1S,7S,10R,13R)-7-acetoxy-4,8,13-trimethyl-11-oxabicyclo[8.3.0]trideca-4(E),8(Z)-dien-12-one) by X-ray diffraction analysis. 2D1H−1H (COSY) and13C−1H (COSY) NMR spectroscopy was used for assigning the1H and13C NMR signals in the spectra of ajanolide A.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 167–170, January, 1998. 相似文献
29.
V. Kulcitki M. Grin’ko A. Barba N. Ungur P. F. Vlad 《Chemistry of Natural Compounds》2007,43(3):268-273
A mixture of (13E,17E)-12-phenylsulfonylbicyclogeranylfarnesol tetrahydropyranyl ether (8) and (13E,17E)-12-phenylsulfonylbicyclogeranylfarnesol (9) was formed by superacid low-temperature cyclization of exclusively trans-8-phenylsulfonylgeranylfarnesol tetrahydropyranyl
ether (1). The structures of 8 and 9 were established using spectral data. The optically active form of 9 was also confirmed by retrosynthesis from (+)-sclareolide (10).
__________
Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 224–228, May–June, 2007. 相似文献
30.
A. A. Panasenko E. C. Gorincioi A. N. Aricu E. A. Barcari K. Deleanu P. F. Vlad 《Russian Chemical Bulletin》2004,53(12):2700-2705
One- and two-dimensional homo- and heteronuclear correlation proton, carbon, proton—proton, and proton—carbon NMR spectra of fifteen drimanic sesquiterpenoids: 11,12-dibromodrima-5,8-dien-7-one, drim-8-en-7-one, 11-hydroxydrim-8-en-7-one, 11,12-dihydroxydrim-8-en-7-one, 11-hydroxy-11,12-epoxydrim-8-en-7-one, 11-hydroxy-11,12-epoxydrim-8-en-7-one, 8,9-epoxydriman-7-one, 8,9-epoxydriman-7-ol, 11,12-diacetoxydrim-8-en-7-ol, drimane-7,8,11-triol, 7,8-isopropylidenedioxydriman-11-al, 9, 11-dihydroxydrim-7-en-6-one, drimane-7,8,9-triol, drimane-7,8,11-triol, and drim-8-ene-7,11,12-triol were studied. The proton and carbon chemical shifts were assigned.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2589–2594, December, 2004. 相似文献