Publications by authors named "Ji Kai Liu"

Five brasilane-type sesquiterpenoids, including four previously undescribed compounds named xylaribrasilaids A-D, along with a known analogue, were isolated from the ethyl acetate extracts of solid fermentation from Xylaria nigripes. X. nigripes, a traditional Chinese medicinal fungus utilized for treating various ailments such as insomnia, trauma, and depression, has garnered attention due to its pharmacological potential.

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Nine new compounds (-), including four dihydrochalcone glycosides, two dibenzofuran glycosides, and two biphenyl glycosides, were isolated from the leaves of the medicinal plant collected in Shennongjia Forestry District (Hubei, China). Their structures were elucidated by comprehensive spectroscopic techniques, including HRESIMS and NMR spectra. All compounds were tested by preliminary biological evaluation for their α-glucosidase inhibitory and NO production activities.

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CRISPR technology has been widely used for gene editing in various species,but the genetic manipulation in basidiomycete mushrooms is still notoriously difficult for unknown endogenous promoters and inefficient DNA delivery. Steccherinum ochraceum is a white rot basidiomycete fungus with abundant secondary metabolites and plays an important ecological role worldwide. To facilitate the study of gene function in S.

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Article Synopsis
  • Twelve new isoindolin-1-one compounds, named erinacenones A-L, were discovered from the medicinal fungus through liquid cultures.
  • Their structures were determined using various spectroscopic techniques, and the absolute configuration was figured out by comparing optical rotations to literature values.
  • Notably, two pairs of these compounds are isomers differing by one double bond, and two of the compounds showed cytotoxic effects against MCF-7 cancer cell lines with IC values of 24.7 and 18.4 μM.
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In the context of oxygen evolution reaction (OER), the construction of high-valence transition metal sites to trigger the lattice oxygen oxidation mechanism is considered crucial for overcoming the performance limitations of traditional adsorbate evolution mechanism. However, the dynamic evolution of lattice oxygen during the reaction poses significant challenges for the stability of high-valence metal sites, particularly in high-current-density water-splitting systems. Here, we have successfully constructed Co-O-Fe catalytic active motifs in cobalt-iron Prussian blue analogs (CoFe-PBA) through oxygen plasma bombardment, effectively activating lattice oxygen reactivity while sustaining robust stability.

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L3SO is a fungus isolated from the rhizospheric soil of the chloroplast-deficient plant . A chemical study on the rice fermentation of this fungus led to the isolation and identification of two cage-like polyketides, penidaleodiolide A () and its biosynthetic-related congener penidaleodiolide B (). The structures of and were determined by a combination of extensive spectroscopic analysis, biosynthetic consideration, chemical derivatization, and computational methods.

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  • Proton exchange membrane (PEM) electrolysis is a leading method for producing green hydrogen but faces challenges due to the high use of platinum-group metals (PGM).
  • A new approach involves creating stable palladium hydride (PdH) nanoclusters anchored on tungsten carbide (WC) supports, enhancing hydrogen adsorption/desorption efficiency during electrolysis.
  • This PdH-WC catalyst achieves impressive performance with a very low palladium loading, operating at a current density of 1 A/cm and maintaining stability over 200 hours, offering a promising direction for future electrocatalyst design.
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  • The study focused on the fungus Stereum hirsutum, leading to the extraction of 12 isopentenyl benzene derivatives, including six new compounds named stereuins A-F.
  • The structures of these compounds were confirmed using NMR and mass spectrometry, with stereuins A-C being benzoate derivatives that include fatty acid components.
  • Stereuin A showed potential for promoting nerve cell growth in vitro, while compounds D-F demonstrated antibacterial properties against Staphylococcus aureus, with stereuin F being nearly as effective as penicillin G.
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Twenty-nine sesquiterpenoids, including pseudoguaiane-type (1-11), eudesmane-type (12-23), and carabrane-type (24-29), have been identified from the plant Carpesium abrotanoides. Of them, compounds 1-4, 12-15, and 24-27, namely carpabrotins A-L, are twelve previously undescribed ones. Compound 3 possessed a pseudoguaiane backbone with a rearrangement modification at C-11, C-12 and C-13, while compound 4 suffered a carbon bond break between the C-4 and C-5 to form a rare 4,5-seco-pseudoguaiane lactone.

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The , also known as "Feng Dan" have a crucial role in folk medicine to treat lumbar muscles strain, knee osteoarthritis and cervical spondylosis. In this study, four new phenolic compounds, specifically Paeoniaostiph A-E (-) phenolic compounds were characterised through spectroscopic techniques, including 1D and 2D NMR, HRESIMS, UV, IR, and electronic circular dichroism computations to explore their structures. Cytotoxicity and NO production inhibition of the new phenolic compounds were also studied.

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Article Synopsis
  • A new method has been developed that uses a cooperative Rh/achiral phosphoric acid for a [3+3] cycloaddition reaction involving carbonyl ylides and quinone monoimines.
  • This method allows for the rapid and efficient construction of highly complex oxa-bridged benzofused dioxabicyclo[3.2.1]octane structures, resulting in good to excellent yields while maintaining mild reaction conditions.
  • The practicality of this approach is highlighted by successful gram-scale syntheses and subsequent transformations of the products into various functionalized oxa-bridged heterocycles.
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  • Continued research on bioactive alkaloids led to the discovery of five new alkaloids (ophiorglucidines A-E) and seven known ones from Ophiorrhiza japonica.
  • The unique structure of one of the new alkaloids, characterized as a hexacyclic skeleton, marks the first report of this type with a double bridge between the indole and monoterpene parts.
  • Alkaloids 2 and 3 demonstrated strong inhibitory effects on xanthine oxidase, outperforming the common inhibitor allopurinol, with their effectiveness linked to a specific carbonyl group in their structure.
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Finding safe and environmentally friendly fungicides is one of the important strategies in modern pesticide research and development. In this work, the antipathogenic effects of the fungus against the anthracnose pathogen were studied. The EtOAc extract of showed remarkable antifungal activity against with an inhibition rate of 50% at 256 μg/mL.

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Phellintremulin A (1), a rearranged sesquiterpenoid with an unprecedented bicyclic backbone, and two previously unreported illudane-type sesquiterpenoids, namely phellintremulin B (2) and phellintremulin C (3), together with two known analogues (±)‒4 and (±)‒5, were isolated from cultures of the medicinal fungus Phellinus tremulae. Their structures and absolute configurations were established by means of spectroscopic data and HRESIMS analyses, as well as ECD and NMR calculations. A plausible biogenesis for 1 was discussed.

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Article Synopsis
  • - Carpesabrolide A (1) is a unique hybrid compound that combines fumaric acid and guaiane sesquiterpenoid structures, extracted from a traditional medicinal plant.
  • - The compound's structure and configuration were determined using advanced techniques like spectroscopy and single crystal X-ray diffraction.
  • - Carpesabrolide A (1) demonstrates notable anti-inflammatory properties by significantly inhibiting nitric oxide (NO) production, with an inhibitory concentration (IC) value of 2.7 μM.
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Two new quinoline alkaloids with an α, β-unsaturated amide side chain, xylarinines A and B (1 and 2), were isolated from the ethyl acetate extracts of Xylaria longipes solid fermentation. The structures of these were primarily determined though NMR and HRESIMS data analysis. The absolute configuration of compound 1 was assigned using experimental and calculated ECD data.

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Eight previously undescribed chromones eleusineketones A-H (1-8), as well as eight known compounds (9-16), were isolated from the endophytic fungus Bipolaris eleusines. These planar structures were created using an in-depth analysis of their spectral data, which included 1D, 2D, and HRESIMS data. Furthermore, the absolute configurations of compounds 1, 2, and 6 were determined by spectroscopic analysis and quantum chemical computational approaches, and compound 5 was determined by single-crystal X-ray diffraction analysis.

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In this study, two previously undescribed nitrogen-containing compounds, penisimplicins A () and B (), were isolated from JXCC5. The structures of and were elucidated on the basis of comprehensive spectroscopic data analysis, including 1D and 2D NMR and HRESIMS data. The absolute configuration of was determined by Marfey's method, ECD calculation, and DP4+ analysis.

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Herein, a novel cascade gold(I)-catalyzed hydroarylation of alkynylindoles and subsequent Diels-Alder cycloaddition with electron-deficient alkynes and alkenes is described. A variety of azepino-fused hydrocarbazoles and carbazoles were obtained in moderate to excellent yields. Key features of this methodology are low catalyst loadings, high regioselectivity, broad functional group tolerances, access to important heterocycles, and 100% atom economy.

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Two previously undescribed ergosterols containing a highly conjugated ring system, psathrosterols A and B ( and ), have been isolated from the fungus . Their structures with absolute configurations were established by extensive spectroscopic methods, as well as single crystal X-ray diffraction. Compounds and showed inhibitory activity against NO production with IC values of 22.

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A series of terpenoids (1-17), comprising six new compounds designated bipolariterpenes A-F (1-6) and eleven recognized compounds (7-17), were isolated from the wheat culture of the potato endophytic fungus Bipolaris eleusines. Their structures and stereochemistry were clarified by HRESIMS, NMR, DP4 + probability analyses, and computations for electronic circular dichroism (ECD). All compounds are made up of six meroterpenoids, four sesterterpenes and seven sesquiterpenes.

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Four undescribed cytochalasins () were isolated from the endophytic fungus . Structurally, boerelasin A () represents the first example of a cytochalasin with a rare 5/5 bicyclic carbon core. Boerelasin B () possesses an unprecedented 5/6/5/6/8 pentacyclic ring system.

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Seven previously undescribed cytochalasans, namely, boerechalasins A-G, together with one analogue, were characterized from the solid culture of the fungus Boeremia exigua. Their structures and absolute configurations were elucidated on the basis of extensive spectroscopic analysis as well as electronic circular dichroism calculations. Remarkably, boerechalasin F possessed an unusual sulfoxide moiety that might be derived from methionine, while boerechalasin G had an unusual 5-methylcyclohexane-1,2,3-triol substituent at N-2 position.

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A rhodium(III)-catalyzed redox-neutral spiroannulation approach to access the spiro[benzo[][1,4]oxazine-benzo[]chromene skeleton is described in this contribution. A variety of spiro[5.5]-heterocyclic scaffolds were obtained in moderate to excellent yields under mild conditions.

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Four previously undescribed chamigrane sesquiterpenes, namely steccherins A-D, have been isolated from the fungus Steccherinum ochraceum. Their structures were elucidated by extensive spectroscopic analysis, as well as computational methods and single crystal X-ray diffraction. Steccherins A and B possess previously undescribed backbones which might be derived from normal chamigrane sesquiterpenes, especially that steccherin A possesses a spiro[5.

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