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Xiao‐Dong Li Feng‐Ping Miao Xiao‐Rui Liang Nai‐Yun Ji 《Magnetic resonance in chemistry : MRC》2014,52(5):247-250
One new meroterpene, arisugacin K (1), and four known ones, arisugacin J (2), arisugacin G (3), arisugacin C (4), and territrem C (5), were isolated from the culture of Penicillium echinulatum pt‐4, an endophytic fungus isolated from the marine red alga Chondrus ocellatus. The structure and the absolute configuration of 1 were unambiguously elucidated by spectroscopic analyses and quantum chemical calculations, which further resulted in the assignments of absolute configurations for the other arisugacins and territrems. Compound 1 showed inhibitory activity against Escherichia coli with an inhibition diameter 8 mm at 30 µg/disk and 4 exhibited lethality against Artemia salina with an LC50 of 48.6 µg/ml. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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A new oxylipin, (8E,12Z)-10,11-dihydroxyoctadeca-8,12-dienoic acid (1), a new steroid, 3β,4α-dihydroxy-26-methoxyergosta-7,24(28)-dien-6-one (2), and four known steroids, episterol (3), (22E,24R)-ergosta-7,22-dien-3β,5α,6α-triol (4), (22E,24R)-ergosta-5,22-dien-3β-ol (5), and (22E,24R)-ergosta-4,6,8(14),22-tetraen-3-one (6), were isolated from the cultures of Aspergillus flavus, an endophytic fungus isolated from the marine red alga Corallina officinalis. Their structures and relative stereochemistry were elucidated by 1D, 2D NMR and mass spectroscopic techniques. 1 and 2 exhibited low activity to inhibit acetylcholinesterase and no activity against plant pathogenic fungi Colletotrichum lagenarium and Fusarium oxysporum. 相似文献
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Hao‐Fen Sun Xiao‐Ming Li Ling‐Hong Meng Chuan‐Ming Cui Shu‐Shan Gao Chun‐Shun Li Bin‐Gui Wang 《Helvetica chimica acta》2013,96(3):458-462
Two new secoanthraquinone derivatives, wentiquinones A ( 1 ) and B ( 2 ), together with the eight known compounds 3 – 10 , were isolated from the culture extracts of Aspergillus wentii EN‐48, an endophytic fungus derived from an unidentified marine brown algal species of the genus Sargassum. The structures of these compounds were elucidated on the basis of extensive spectroscopic analysis. 相似文献
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Xiao‐Dong Li Wei Ding Feng‐Ping Miao Nai‐Yun Ji 《Magnetic resonance in chemistry : MRC》2012,50(2):174-177
Three new halogenated chamigrane sesquiterpenes, laurokamin A (1), laurokamin B (2), and laurokamin C (3), and four known halogenated chamigrane sesquiterpenes, 10‐bromo‐α‐chamigrene (4), 10‐bromo‐β‐chamigrene (5), 2,10‐dibromo‐3‐chloro‐β‐chamigrene (6), and obtusane (7), were isolated from the marine red alga Laurencia okamurae collected from the coast of Rongcheng, China. The structures of these compounds were unambiguously identified by one‐ and two‐dimensional NMR and mass spectroscopic methods. The antimicrobial activity of compounds 1–3 was evaluated. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Guo Z She Z Shao C Wen L Liu F Zheng Z Lin Y 《Magnetic resonance in chemistry : MRC》2007,45(9):777-780
Two new natural products, named paecilin A (1) and B (2), together with two known compounds secalonic acid D (3) and (11)-cytochalasa-6(12),13-diene-1,21-dione-16,18-dimethyl-7-hydroxy-10-phenyl-(7S*,13E,16S*,18S*) (4), were isolated from the mangrove endophytic fungus, Paecilomyces sp. (tree 1-7) from the South China Sea. 1D and 2D NMR experiments including COSY, HMQC, and HMBC were used for the determination of their structures. In our cytotoxicity assays, secalonic D (3) showed cytotoxicity toward KB cells with IC(50) < 1 microg ml(-1) and inhibiting human topoisomerase I with IC(50) at 0.16 micromol ml(-1). 1, 2, and 4 showed no activity to KB cells. 相似文献
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Shao C Wang C Wei M Gu Y Xia X She Z Lin Y 《Magnetic resonance in chemistry : MRC》2008,46(11):1066-1069
Two new xanthones, 8-(methoxycarbonyl)-1-hydroxy-9-oxo-9H-xanthene-3-carboxylic acid (1) and dimethyl 8-methoxy-9-oxo-9H-xanthene-1,6-dicarboxylate (2) and one known xanthone methyl 8-hydroxy-6-methyl-9-oxo-9H-xanthene-1-carboxylate (3) were isolated from the culture broth of the mangrove fungus Penicillium sp. (ZZF 32#) collected from the South China Sea. Their structures were established by comprehensive analysis of one-dimensional (1D) and two-dimensional (2D) NMR data. The structure of compound 3 was confirmed by X-ray crystallography, which led to the suggestion that janthinone (4) might have the same structure as 3. Compounds 1-3 were inactive against KB or KBv200 cells during cytotoxicity evaluations. 相似文献
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Fan Liu Qing Li Hong Yang Xiao‐Ling Cai Xue‐Kui Xia Sheng‐Ping Chen Meng‐Feng Li Zhi‐Gang She Yong‐Cheng Lin 《Magnetic resonance in chemistry : MRC》2009,47(5):453-455
Two new natural products, tenelate A ( 1 ) and B ( 2 ), together with the known compound, tenellic acid C ( 3 ), were isolated from the mangrove endophytic fungus Talaromyces sp. (SBE‐14), from the South China Sea. Their structures were elucidated by spectroscopic methods, mainly 1D and 2D NMR techniques. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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Eliška Procházková Lucie Čechová Petr Jansa Martin Dračínský 《Magnetic resonance in chemistry : MRC》2012,50(4):295-298
Four‐ and five‐bond heteronuclear J‐couplings between the hydrogen H‐8 and carbons C‐6 and C‐2 in a series of 7‐ and 9‐benzyl substituted purine derivaties with variuous substituents in positions 2 and 6 were studied by coupled 13 C NMR and H,C‐HMBC experiments and by DFT calculations. We have found that for some of the derivatives, the five‐bond coupling H8‐C2 is higher than the four‐bond H8‐C6 coupling, which is also evidenced by a stronger crosspeak in the HMBC. This finding contradicts the generally accepted opinion that only strong three‐bond crosspeaks and one weak four‐bond H8‐C6 crosspeak can be observed in the HMBC spectra of purine derivatives. The misinterpretation of HMBC spectra may lead to an incorrect determination of the purine derivatives' structure. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Complete (1)H and (13)C NMR signal assignments of two lactucin-type sesquiterpene lactone glycosides, derivatives of 11β,13-dihydrolactucin, isolated from roots of Picris conyzoides, were achieved by one- and two-dimensional NMR experiments, allowing the correction of previously published data for cichorioside B and the structure elucidation of its new ester with 3-hydroxy-2-methylpropanoic acid. In addition, seven known sesquiterpene lactones and three phenolic compounds were isolated from the plant material. 相似文献
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M. Dora Carrión Luisa C. López‐Cara Mariem Chayah Duane Choquesillo‐Lazarte Miguel A. Gallo Antonio Espinosa Antonio Entrena M. Encarnación Camacho 《Magnetic resonance in chemistry : MRC》2012,50(7):515-522
The 1H and 13C NMR resonances of twenty‐seven 2,2‐dimethyl‐5‐(2‐nitrophenyl‐5‐substituted)‐2,3‐dihydro‐1,3,4‐thiadiazoles, and twenty‐seven 3‐acyl‐5‐(2‐amino‐5‐substituted)‐2,2‐dimethyl‐2,3‐dihydro‐1,3,4‐thiadiazoles were assigned completely using the concerted application of one‐dimensional and two‐dimensional experiments (DEPT, HMQC and HMBC). NOESY experiments, X‐ray crystallography and conformational analysis confirm the preferred conformation of these compounds. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Hao Gao Kui Hong Guo‐Dong Chen Chuan‐Xi Wang Jin‐Shan Tang Yang Yu Miao‐Miao Jiang Man‐Mei Li Nai‐Li Wang Xin‐Sheng Yao 《Magnetic resonance in chemistry : MRC》2010,48(1):38-43
Two new oxidized sterols 1 and 2 were obtained from the active fraction of a mangrove fungus Aspergillus awamori isolated from the soils around the mangrove plant Acrostichum speciosum. Their structures were elucidated using spectroscopic methods as 22E‐7α‐methoxy‐5α,6α‐epoxyergosta‐8(14),22‐dien‐3β‐ol (1) and 22E‐3β‐hydroxy‐5α,6α,8α,14α‐diepoxyergosta‐22‐en‐7‐one (2). The NMR data and complete assignments for both DMSO‐d6 and CDCl3 were given. Their cytotoxic activity against A549 cell line was evaluated. Furthermore, the detailed conformation analysis for ring B (cyclohexene oxide system) of sterol 1 was given on the basis of NOEs. The endo‐boat conformation was considered as the preferred conformation for ring B rather than half‐chair conformation. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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Zhongjing Huang Ruiyun Yang Xianhong Yin Zhigang She Yongcheng Lin 《Magnetic resonance in chemistry : MRC》2010,48(1):80-82
The structure elucidations and complete 1H and 13C NMR assignments are reported for two new xanthone derivatives: 1,7‐dihydroxy‐2‐methoxy‐3‐(3‐methylbut‐2‐enyl)‐9H‐xanthen‐9‐one (1) and 1‐hydroxy‐4,7‐dimethoxy‐6‐(3‐oxobutyl)‐9H‐xanthen‐9‐one (2). Both of these secondary metabolites were isolated from the fermentation medium of a mangrove endophytic fungus (No. ZH19). High‐resolution electron impact mass spectrometry (HREIMS), Fourier transform infrared (FT‐IR) absorption spectrometry, and NMR experiments including gCOSY, gHMQC, and gHMBC were used for the determination of the structures and NMR spectral assignments. Preliminary pharmacological test showed that compounds (1) and (2) inhibited KB cells with IC50 values of 20 and 35 µmol/ml, and KBV200 cells with IC50 values of 30 and 41 µmol/ml, respectively. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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One unusual triterpenoid derivative, ilekudinchoside E (1), was isolated from the leaves of Ilex kudincha. The structure was established by various spectroscopic techniques, including one‐ and two‐dimensional NMR, HRTOFMS and CD spectra. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Aline Lima de Oliveira Carlos Henrique Alves de Oliveira Laura Maia Mairink Francine Pazini Ricardo Menegatti Luciano Morais Lião 《Magnetic resonance in chemistry : MRC》2011,49(8):537-542
Complete assignment of 1H and 13C NMR chemical shifts and J(1H/1H and 1H/19F) coupling constants for 22 1‐phenyl‐1H‐pyrazoles' derivates were performed using the concerted application of 1H 1D and 1H, 13C 2D gs‐HSQC and gs‐HMBC experiments. All 1‐phenyl‐1H‐pyrazoles' derivatives were synthesized as described by Finar and co‐workers. The formylated 1‐phenyl‐1H‐pyrazoles' derivatives were performed under Duff's conditions. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Xiu Lan Xin Guowei Yang Zhan Ping Gou Ji Hong Yao Rong Lan Xiao Chi Ma 《Magnetic resonance in chemistry : MRC》2010,48(2):164-167
Five hydroxylated derivatives of glycyrrhetinic acid by Mucor polymorphosporus were isolated. Among them, 6β, 7β‐dihydroxyglycyrrhentic acid (2) and 27‐hydroxyglycyrrhentic acid (3) are new compounds. Their chemical structures were identified by spectral methods including 2D‐NMR. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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Complete 1H and 13C NMR assignments of aurasperone A and fonsecinone A, two bis-naphthopyrones produced by Aspergillus aculeatus 总被引:1,自引:0,他引:1
Campos FR Barison A Daolio C Ferreira AG Rodrigues-Fo E 《Magnetic resonance in chemistry : MRC》2005,43(11):962-965
Complete assignments of 1H and 13C NMR chemical shifts of the polyketides aurasperone A and fonsecinone A were made by means of nuclear Overhauser enhancement and heteronuclear NMR correlation experiments. These compounds were isolated for the first time from Aspergillus aculeatus, an endophytic fungus obtained from leaves of Melia azedarach(Meliaceae). 相似文献