共查询到20条相似文献,搜索用时 15 毫秒
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Edione F. Canzi Fernando M. dos Santos Emanuelle K. Meneghetti Beatriz Helena L.N. Sales Maia João M. Batista 《Tetrahedron letters》2018,59(2):135-137
Dibenzoylmethanes (DBMs) belong to a small group of flavonoids, known as β-hydroxychalcones, rarely found in nature. Despite their biological and chemotaxonomic importance, the absolute configuration of C-8 substituted DBMs has never been reported. Herein, the absolute stereochemistry of 2′-methoxy-8-(α-α-dimethylallyl)-[3′,4′:4″,5″]-furan-dibenzoylmethane is determined using the VCD exciton chirality method, which may be safely applied to other members of this class. 相似文献
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AbstractPholiotone A (1), a new polyketide derivative, with tetrahydrobenzofuran-4(2H)-one skeleton, together with four known compounds, trichodermatides A (2) and B (3) and koninginins B (4) and E (5), were isolated from the crude extract of Pholiota sp. The structures of all the isolated compounds were determined mainly by NMR experiments, the modified Mosher method and electronic circular dichroism (ECD) calculations. The antifungal and cytotoxicity of all isolates were evaluated. 相似文献
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Jin-Xiu Zhang Jian-Hua Lv Li-Qiang Zhao Xiao-Xi Shui Jun Zhang 《Natural product research》2020,34(9):1246-1249
AbstractChemical investigation of Paxillus involutus lead to the isolation of a new coumarin derivative coumarin-pi (1), and three known compounds (2-4). The structure of the new compound was elucidated by interpretation of 1D and 2D NMR data. Compound 1 possesses a rare benzofuranylcoumarin skeleton. The isolated compounds were evaluated for antioxidant activities and coumarin-pi (1) exhibited significant activity with IC50 value of 16.3?μg/mL. 相似文献
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David T. Coxon Anthony M.C. Davies G.Roger Fenwick Ron Self John L. Firmin David Lipkin Norman F. Janes 《Tetrahedron letters》1980,21(5):495-498
Agropine, an unusual compound produced in plant tumours was shown by mass spectrometry and proton and carbon-13 nmr spectroscopy to be a bicyclic derivative of glutamic acid and a hexitol sugar. 相似文献
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Myristigranol, a new diarylpropane derivative, was isolated from the methanol extract of Myristica fragrans wood along with one diarylpropanoid and three stilbenoids. The isolated constituents were exhaustingly identified using the analyses of 1D and 2D NMR spectroscopic techniques and comparison of the literatures reported as well. The antioxidant activity was also determined.
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The structure of GdPS is orthorhombic, space group Pmnb; a = 5.3620(5), b = 5.4079(6), c = 16.742(2)Å, Z = 8. It is a distorted derivative of the tetragonal PbFCl structure (a0, c0) with . The distortions are due to the formation of phosphorus chains. This structure type is found also in other rare-earth sulfopolyphosphides, e.g., with Ln = La···Sm, Tb···Tm, Y. 相似文献
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Ng'ang'a MM Hussain H Chhabra S Langat-Thoruwa C Krohn K Hussain J Al-Harrasi A Green IR 《Natural product communications》2012,7(2):193-194
A new naphthalene derivative, named eucleanal (1), was isolated from Euclea divinorum Hiern., and its structure elucidated by detailed spectroscopic (1H, 13C NMR, COSY, HMQC, HMBC) and HREIMS analysis. 相似文献
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《Tetrahedron letters》1987,28(15):1693-1696
From the sponge Aplysina aerophoba a new rearranged dibromotyrosinederivative aplysinadiene (9) was isolated. The structure was solved by spectral properties and synthesis. 相似文献
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The synthesis of the new derivatives, 2-methyl-6,7-methylenodioxy-2H-1,2-benzothiazin-3-one-4-(N-phenyl)carboxamide 1,1-dioxide ( 6a ) from natural safrole ( 5 ) is described. The principal feature of this route is brevity and the high overall yield, producing the new analogue in ca. 35% from the natural product. 相似文献
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Li-Jian Ding Wei Yuan Ying-Xin Li Xiao-Jian Liao Huan Sun Qi Peng 《Natural product research》2016,30(14):1633-1638
In continuation of our search for new antibacterial and antioxidant metabolites from sponge-derived fungi, one new tyrosol derivative, hypocrol A (1), together with four known congeners, trichodenol B (2), 4-hydroxyphenethyl acetate (3), 4-hydroxyphenethyl tetradecanoate (4) and 1-oleyltyrosol (5), was isolated from the strain Hypocrea koningii PF04. Their planar structures were unequivocally elucidated by spectroscopic methods and comparison with the literature data. All the compounds displayed weak antibacterial activities against Staphylococcus aureus, methicillin-resistant S. aureus and Escherichia coli, whereas compounds 1 and 2 exhibited a moderate antioxidant efficacy in the DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging assay with IC50 values of 48.5 and 97.4 μg/mL, respectively. 相似文献
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Psychotripine, a trimeric pyrroloindoline derivative with an unprecedented hendecacyclic system bearing a hexahydro-1,3,5-triazine unit, was isolated from the leaves of Psychotria pilifera. The structure was elucidated on the basis of spectroscopic and quantum theory. A possible biogenesis was also postulated. 相似文献
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Bahiensol (1), a new glycerolipid with antimicrobial activity has been isolated from a cultured plasmodium of myxomycete Didymium bahiense var. bahiense and its planar structure was elucidated by spectral data. 相似文献
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Ze Ping Xie Hong Yu Zhang Fu Chao Li Bing Liu Sheng Xiang Yang Hong Peng Wang Yang Pu Yi Chen Song Qin 《中国化学快报》2012,23(8):941-944
One new isobenzofuranone derivative,1,4-dimethoxy-3-(3R*-hydroxy-3R*-methyl-1-tetralone)-1(3H)-isobenzofuran(1),was isolated from the broth of marine Streptomyces sp.M268.The structure was elucidated by spectroscopy characteristics as well as comparison with the literature.Compound 1 exhibited cytotoxicities against human cancer cell,HL-60,A549,and BEL-7402. 相似文献
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Lenta BN Chouna JR Nkeng-Efouet PA Kimbu SF Tsamo E Sewald N 《Natural product communications》2011,6(11):1591-1592
From the methylene chloride extract of the stem bark of Beilschmiedia obscura, a new cyclostachine derivative, obscurine (1), has been isolated, together with six known compounds. The structure of compound 1 was established by spectroscopic methods, including 1- and 2-dimensional NMR techniques. 相似文献
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Macabeo AP Avila JA Alejandro GJ Franzblau SG Kouam SF Hussain H Krohn K 《Natural product communications》2012,7(6):779-780
Villarinol (1), a new alkenoyloxy alkenol metabolite, has been isolated from the dichloromethane extract of Villaria odorata, an endemic Rubiaceae Philippine plant, along with the known compounds stigmasterol and 4-hydroxybenzaldehyde. The structure of 1 was elucidated on the basis of spectroscopic and spectrometric studies. The extracts of V. odorata exhibited moderate inhibition against Mycobacterium tuberculosis H37Rv, based on the colorimetric microplate alamar blue assay. 相似文献