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排序方式: 共有230条查询结果,搜索用时 15 毫秒
1.
Xiongyu Wu Xiaohong Liu Guangce Jiang Yongcheng Lin Willy Chan L. L. P. Vrijmoed 《Chemistry of Natural Compounds》2005,41(1):27-29
A novel metabolite 1, named xyloketal G, was isolated from cultures of marine derived mangrove fungus Xylaria sp. 2508. Its structure was elucidated by analysis of spectroscopic data.__________Published in Khimiya Prirodnykh Soedinenii, No. 1, pp. 22–23, January–February, 2005. 相似文献
2.
Smetanina O. F. Kuznetzova T. A. Denisenko V. A. Pivkin M. V. Khudyakova Yu. V. Gerasimenko A. V. Popov D. Yu. Il"in S. G. Elyakov G. B. 《Russian Chemical Bulletin》2001,50(12):2463-2465
A pentacyclic tritepenoid, 3-methoxyolean-18-ene (miliacin), was isolated for the first time from the marine fungus Chaetomium olivaceum. Its structure was determined on the basis of 2D NMR spectroscopy and X-ray diffraction data. 相似文献
3.
Ying WANG Su Juan WANG Shun Yan MO Shuai LI Yong Chun YANG Jian Gong SHI Institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College 《中国化学快报》2006,(4)
A new abietane diterpene 12-hydroxy-7-oxo-5, 8, 11, 13-tetraene-18, 6-abietanolide, together with a new natural sterol stigmasta-7, 22-diene-3β, 5α, 6α-triol have been isolated from the fruiting body of the fungus Phellinus igniarius. Their structures were elucidated by spectroscopic methods including 2D NMR techniques. 相似文献
4.
Two new sesterterpenes, 6-epi-ophiobolin G (1) and 6-epi-ophiobolin N (3), and six known ophiobolins were isolated from the extracts of the fungus, Emericella variecolor GF10, which was separated from marine sediment. The planar structures of the new compounds were deduced from analysis of the 2D NMR spectra, and the stereochemistry was determined by extensive examination of the NOESY spectrum. Additionally, the configuration of the C-6 proton in ophiobolin G (2) was revised from α to β, and the unsolved stereochemistry of ophiobolin H (4) was determined by its physicochemical evidence and the chemical correlation with ophiobolin K (8). Ophiobolin K (8) showed cytotoxic activity against various tumor cell lines, including adriamycin-resistant mouse leukemia cells (P388), with IC50 of 0.27-0.65 μM. 相似文献
5.
A new polyoxygenated dihydropyrano[2,3-c]pyrrole-4,5-dione derivative, pyranonigrin F (1), together with a related known compound, pyranonigrin A (2), were isolated and identified from Penicillium brocae MA-231, an endophytic fungus obtained from the fresh tissue of the marine mangrove plant Avicennia marina. The structures of these metabolites were determined based on comprehensive spectral interpretation and the absolute configuration of compound 1 was established by X-ray crystallographic analysis. Compounds 1, and 2 showed potent activity against a broad spectrum of human-, aqua-, and plant-pathogens. 相似文献
6.
肉豆蔻中赭曲霉毒素的测定及赭曲霉毒素产毒菌的分离鉴定 总被引:1,自引:0,他引:1
建立了同时测定肉豆蔻中3种赭曲霉毒素的超高效液相色谱-串联质谱法(UPLC-MS/MS)。样品经70%甲醇超声提取,HLB柱净化,采用Agilent Proshell 120 EC C18色谱柱,以乙腈(含0.1%甲酸)-水(含0.1%甲酸)为流动相进行梯度洗脱,于电喷雾离子源正负离子模式下多反应监测模式检测。结果表明,肉豆蔻基质中3种赭曲霉毒素基质效应为91.0%~112.0%,采用基质匹配标准曲线法定量时各浓度范围下线性关系良好(R2>0.999)。样品在高、中、低3个浓度加标水平下,回收率为63.3%~88.4%,相对标准偏差(RSD)小于6.0%,检出限(LOD)和定量限(LOQ)分别为0.1~1.0μg/kg和0.3~3.0μg/kg。另从肉豆蔻中分离得到一株产毒菌,采用紫外荧光筛选、形态学鉴定、DNA测序结合液质联用检测的方法最终鉴定为菌核曲霉。 相似文献
7.
AbstractA search for bioactive secondary metabolites from the endophytic fungus Fusarium chlamydosporum, isolated from the root of Suaeda glauca, led to the isolation of three indole derivatives (1–3), three cyclohexadepsipeptides (4–6), and four pyrones (7–10). The structures of new (1) and known compounds (2–10) were elucidated on the basis of extensive spectroscopic analysis. All these compounds were evaluated for phytotoxic, antimicrobial activities, and brine shrimp lethality. Compound 1 showed significant phytotoxic activity against the radicle growth of Echinochloa crusgalli, even better than the positive control of 2,4-D. Cyclohexadepsipeptides (4–6) and pyrones (7–10) exhibited brine shrimp lethality, especially 4 and 7 with the LD50 values of 2.78 and 7.40?μg mL?1, respectively, better than the positive control. 相似文献
8.
Xiaojing Lü Gang Chen Zhanlin Li Yuhong Zhang Zaiying Wang Weiwei Rong Yuehu Pei Huaqi Pan Huiming Hua Jiao Bai 《Helvetica chimica acta》2014,97(9):1289-1294
One new and three known spiro‐dioxynaphthalene compounds, related to palmarumycins, were isolated from the extracts of fungus Lasiodiplodia pseudotheobromae XSZ‐3. Their structures were established by spectroscopic methods (1D‐ and 2D‐NMR, HR‐ESI‐MS, etc.). The absolute configuration of 1 was determined by comparison of quantum‐chemical TDDFT (time‐dependent density‐functional theory) calculated and experimental ECD (electronic circular dichroism) spectra. The cytotoxic activities of 1 – 4 against HL‐60 cell line were evaluated by trypan blue‐staining assay. 相似文献
9.
采用微波消解ICP-AES法同时测定了茯苓、桑黄和桦褐孔菌子实体中Ca、Mg、Fe、Zn、Cu、Mn、Se和Cr 8种微量元素。结果显示,3种药用真菌中均含有这8种元素,其中茯苓样品中Ca和Fe含量最高,为212.36μg.·g 1和164.08μg.g-1;桑黄样品中Mn、Zn和Se含量最高,为22.62μg.g-1、91.03μg.·g 1和2.68μg.g-1;而桦褐孔菌样品中Mg、Cu和Cr含量最高,分别是953.60μg.g-1、10.25μg.g-1和2.59μg.·g 1。检出限<0.008μg.mL-1,方法简便、可靠,具有良好的精密度和准确度。 相似文献
10.