Publications by authors named "Yin-Ke Li"

Phytochemical studies on cigar tobacco leaves led to the isolation of 18 ionone-type compounds, including previously undescribed cigatobanes E () and F (). Additionally, compounds vomifoliol acetate (, dehydrovomifoliol (, 8,9-dihydromegastigmane-4,6-diene-3-one (, 7,8-epoxyblumenol B (, 3-oxoactinidol (), and loliolide acetate (), 4-hydroxy-dihydroactinidiolide (), were found in tobacco leaves for the first time. The structural elucidation of all compounds was accomplished through rigorous spectral analysis.

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Article Synopsis
  • Researchers investigated the antifungal properties of a fermentation extract from Aspergillus fumigatus against tobacco powdery mildew caused by Golovinomyces cichoracearum, isolating 14 indole alkaloid derivatives, seven of which were newly identified.* -
  • Among the new compounds, 1-3 were rare tricyclic indole alkaloids, and compounds 6 and 7 introduced a new structural framework, showcasing the unique diversity of these natural products.* -
  • The study revealed that compounds 7 and 9 exhibited strong antifungal activity with inhibition rates of 82.6% and 85.2% respectively, surpassing the positive control carbendazim, and contributed to enhanced plant
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In this study, seven novel anthraquinones (1-7) and four described anthraquinones (8-11) were purified from Nicotiana tabacum-derived Aspergillus oryzae YNCA1220. It is worth noting that only analogs of 4 and 5 have been reported as natural products to date, while the nuclei of compounds 1-3, 6 and 7 were isolated for the first time in nature. Among them, compounds 1-3 bear an unusual anthra[2,3-b]furan-9,10-dione nucleus, 4 and 5 possess a rare 3-methyl-1H-pyrrol-2-yl substituent, and 6 and 7 are new framework anthraquinones bearing a 6-methyl-1,7-dihydro-2H-azepin-2-one ring.

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Article Synopsis
  • Bioactive substances from microbial endophytes have potential uses in medicine, agriculture, and industry.
  • Researchers conducted a phytochemical study on fungal strain sp. 0338, resulting in the isolation of three new and five known alkaloids, with their structures confirmed through advanced spectroscopic methods.
  • The isolated compounds were tested for anti-MRSA activity, showing notable inhibition with inhibitory zones measuring 15.2, 14.6, and 13.4 mm, respectively.
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Background: Natural products are important sources of biopesticides to control plant virus, and flavonoids are identified as promising anti-tobacco mosaic virus (TMV) agents. Since Desmodium caudatum is a rich source of flavonoids, this study focuses on the discovery of the new anti-TMV active flavonoids from D. caudatum and their possible mode of action.

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() is a perennial herb of leguminosae, which increasingly being grown as a forage in China. In our search for original bioactive metabolites from plants, the phytochemical reinvestigation of the was carried out, which led to the isolation of three new (-) and six known (-) chromones. Their structures were confirmed by spectroscopic methods, including extensive 1D and 2D NMR techniques.

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Nicotiana tabacum (tobacco) has attracted interest as one of the most economically important industrial crops widely cultivated in China, whose dried leaves are popularly consumed medicinally and recreationally by human societies. In this study, five undescribed alkaloids derivatives, isoaspergillines A-E, together with eight known alkaloids, notoamide D, (1R,4S)-4-benzyl-1-isopropyl-2,4-dihydro-1H-pyrazino-[2,1-b]quinazoline-3,6-dione, protuboxepin K, notoamide C, notoamide M, deoxybrevianamide E, cyclo (D-Pro-L-Trp), and versicolamide B, were obtained from the culture of the Nicotiana tabacum-derived fungus Aspergillus versicolor. Their structures were mainly elucidated through comprehensive analyses of spectroscopic data.

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In previous studies, several isoindolin-1-one analogs that exhibited significant anti-tobacco mosaic virus (anti-TMV) activities were isolated from Nicotiana tabacum. Since gene-editing mutants provide a new sample for the discovery of active metabolites, we focused on the stems of YN-18-23 (a mutant N. tabacum for gene editing with the alkaloid metabolic pathway cultivated by Yunnan Tobacco Company), which led to the isolation of four new (1-4) and four known (5-8) isoindolin-1-ones.

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Three new isochromenes, (5-methoxy-7-prenyl-1-isochromen-3-yl)methanol (), 3-(3-(hydroxymethyl)-5-methoxy-1-isochromen-7-yl)propan-1-ol (), and (5-methoxy-7-methyl-1-isochromen-3-yl)methanol (), along with three known analogues (-) were isolated from the fermentation products of a -derived endophytic fungus . Their structures were elucidated by spectroscopic methods, including extensive 1 D and 2 D NMR techniques. Compounds - and were evaluated for their anti-tobacco mosaic virus (anti-TMV) activities.

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Indole alkaloids have attracted widespread attention of chemists and biologists. Therefore, the aim of this study is to screen more bioactivities indole alkaloids from the microorganisms. In this study, five undescribed CPA-type indole alkaloids, aspergillines F-J, and three known CPA-type indole alkaloids, aspergilline A, aspergilline C, and cyclopiamide E, were obtained from the Nicotiana tabacum-derived fungus Aspergillus versicolor.

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A new isoquinoline alkaloid(1) has been isolated from the whole plant of Thalictrum glandulosissimum by using various chromatographic techniques, including silica gel, sephadex, MCI-gel resin, and RP-HPLC, and its structure was determined as 1-(6-hydroxy-7-methylisoquinolin-1-yl) ethantone by physicochemical properties and spectroscopic data. This compound was evaluated for anti-tobacco mosaic virus(TMV) activity. The results showed that it had prominent anti-TMV activity with inhibition rates of 28.

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A new isobenzoisofuran(1) has been isolated from the whole plant of Cassia pumila using various chromatographic techniques, including silica gel, Sephadex, MCI-gel resin, and RP-HPLC, and its structure was determined as 9-(2-hydroxyethyl)-2,2-dimethyl-2H-furo[3,4-g]chromen-6(8H)-one. This compound was also evaluated for its antibacterial activity. The results showed that it had prominent antibacterial activity with MIC_(90) value of(45.

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A new flavone( 1) has been isolated from the whole plant of Cassia nomame by using various chromatographic techniques,including silica gel,Sephadex,MCI-gel resin,and RP-HPLC,and its structure was determined as 8,4'-dimethoxy-7-( 2-oxopropyl)-flavone based on spectroscopic data. The biological activity test showed that this compound displayed potent cytotoxicity against NB4,SH-SY5 Y,PC3,A549 and MCF-7 cell lines with IC values 2. 2,1.

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Two new biphenyls (1 and 2) and three known xanthones (3-5) were isolated from the ethanol extract of the stems of Garcinia tetralata. Structural elucidations of 1-2 were elucidated by spectroscopic methods including extensive 1D- and 2D-nuclear magnetic resonance spectroscopy techniques. Compounds 1-2 showed anti-rotavirus activities with SI above 10.

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Article Synopsis
  • Scientists studied a plant called Garcinia tetralata and found three new chemicals called tetralatabiphenyls A-C.
  • They used special techniques to understand the structure of these new chemicals.
  • The scientists tested the chemicals to see if they could help fight a virus that affects plants, and found that one chemical (3) worked really well, stopping the virus by about 31.1%. Other chemicals also helped a little bit.
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Four new flavones, tobaflavones E-H (1-4), together with two known flavones (5 and 6), were isolated from the leaves of Dali Tiandeng tobacco (a variety of Yunnan local air cured tobacco). Their structures were elucidated by spectroscopic methods, including extensive 1D- and 2D NMR techniques. Compound 2 is the first naturally occurring flavone bearing a (4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)methyl moiety.

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Versicolols A and B (1 and 2), two rare prenylated isocoumarin derivatives, along with five known isocoumarins (3-7) were isolated from the fermentation products of an endophytic fungus Aspergillus versicolor. Their structures were elucidated on the basis of extensive spectroscopic analysis, including 1D- and 2D-NMR techniques. Compounds 1 and 2 were evaluated for their cytotoxicity against five human tumor cell lines.

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Two new isoflavanones, (3R)-7-hydroxy-4'-methoxy-5-methoxycarbonyl-isoflavanone (1) and (3R)-8-hydroxy-4'-methoxy-7-methoxycarbonyl-isoflavanone (2), together with seven known isoflavanones (3-9) were isolated from Desmodium oxyphyllum of the Leguminosae family. Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. Compound 1 showed good cytotoxicity against NB4 and SHSY5Y cell lines with IC50 values of 3.

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Five unusual new prenylated chalcones, renifolins D-H (1-5), were isolated from whole Desmodium renifolium plants. All of their structures were determined by spectroscopic methods including 1D and 2D NMR. All of the isolates were evaluated for cytotoxicity using five tumor cell lines.

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Eight new C-4-alkylated deoxybenzoins (1-8), three new diphenylethylenes (9-11), and five known diphenylethylenes were isolated from Arundina graminifolia. The structures of 1-11 were elucidated by spectroscopic methods including extensive 1D and 2D NMR techniques. Compounds 9-11 are the first naturally occurring diphenylethylenes possessing a hydroxyethyl unit.

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Seven new dibenzocyclooctadiene lignans, marlignans M-S (1-7), four new norlignans, marphenols C-F (8-11), and 21 known compounds (12-32) were isolated from the fruits of Schisandra wilsoniana. The structures of 1-11 were elucidated by spectroscopic methods including 1D- and 2D-NMR techniques and CD experiments. Compounds 1-11 were evaluated for their anti-HIV activities and showed EC(50) values in the range 2.

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Four new neolignans, marphenols G-J (1-4), together with two known ones, were isolated from the leaves and stems of Schisandra wilsoniana. The structures of 1-4 were elucidated by spectroscopic methods, including extensive 1D- and 2D-NMR techniques. New compounds 1-4 were tested for their anti-human immunodeficiency virus (HIV)-1 activities and they showed weak bioactivities.

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Three new dibenzocyclooctadiene lignans, wilsonilignans A-C (1-3), together with nine known ones, were isolated from the fruits of Schisandra wilsoniana. The structures of 1-3 were elucidated by spectroscopic methods including extensive 1D and 2D NMR techniques. Compounds 1-3 were also evaluated for their anti-HIV-1 activities and showed bioactivity with EC(50) values of 3.

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Twelve new dibenzocyclooctadiene lignans, marlignans A-L (1-12), together with 16 known compounds, were isolated from the leaves and stems of Schisandra wilsoniana. The structures of 1-12 were elucidated by spectroscopic methods including 1D- and 2D-NMR techniques. Compounds 1-12 were evaluated for their anti-HIV activities, of which compounds 3, 6, 8, and 12 showed modest activities with therapeutic index values of 13.

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