Publications by authors named "Heng-Yi Yu"

2-Methoxyjuglone, a member of the 1,4-naphthoquinone family, was first obtained through semi-synthesis based on 2-hydroxyjuglone as the precursor in 1966. It has been isolated and identified from different plant species of the Juglandaceae, Sterculiaceae, and Proteaceae families. 2-Methoxyjuglone has been demonstrated to possess a wide range of biological activities, including antitumor, antifungal, and antibacterial activities; in addition, it has been shown to poison fish and inhibit seed germination.

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Objective: Fine particulate matter (PM ) is an air pollutant that has become of great concern in recent years. Numerous studies have found that PM may contribute to lung cancer, but the pathogenesis has not yet been fully elucidated. In this study, we explored the roles of exosomes from bronchial epithelial cells in PM -promoted lung cancer metastasis.

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Twelve new resorcylic acid lactones (RALs) including three new 16-membered RALs (, and ), eight new 14-membered RALs (-), and one new 12-membered RAL (), along with five known 14-membered RALs (-), were identified from the fermentation of the soil-derived fungus sp. sb65. Their structures were established by detailed analyses of 1D and 2D NMR, HRESIMS, and X-ray diffraction crystallography.

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Ten new alkaloids (1-10), including two pairs of enantiomeric mixtures (5a,b and 6a,b), and 15 known analogues (11-25) were obtained from the bark of Pausinystalia yohimbe. The structures of 1-25 were established by spectroscopic methods, and the absolute configurations of compounds 1-10 were resolved by X-ray diffraction and ECD data analyses. The in vitro immunosuppressive activities of selected isolates were tested.

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Nine new lignans (1-9) and ten known analogues (10-19) were isolated from the fruits of Schisandra bicolor var. tuberculata. The structures of compounds 1-9 were established on the basis of spectroscopic data analysis.

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An extensive phytochemical study on the stems and leaves of Schisandra viridis A. C. Smith led to the isolation of two novel highly oxygenated schinortriterpenoids, pre-schisanartanin P (1) and wuweizidilactone Q (2), together with four known ones (3-6).

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Five new triterpenoids, named schiglausins P-T (1-5), together with twelve known analogues (6-17), were isolated from the fruit of Schisandra glaucescens Diels. Their structures were determined by various spectroscopic methods, including HRESIMS, 1D and 2D NMR spectra and CD experiment. Additionally, all these compounds were tested for their cytotoxicities against B16 mouse melanoma cell line.

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Twenty-two new highly oxygenated bisabolane-type sesquiterpenoids, pararubin A-V (1-22), were isolated from the whole plant of Parasenecio rubescens. The structure determination of 1-22, including the assignment of their relative configurations, was accomplished by extensive 1D and 2D NMR spectroscopy. The absolute configuration of pararubin A (1) was established by single-crystal X-ray crystallographic analysis.

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Three novel alkaloids (1-3), together with nineteen known ones (4-22), were isolated from the bulbs of Lycoris longituba. Their structures were elucidated on the basis of extensive spectroscopic analyses, which belong to several Amaryllidaceae alkaloid skeletons. Among them, the harmane-type alkaloids (the new compound 1 and the known compounds 5, 6 and 7) were found for the first time from Lycoris genus.

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Two rare 7,8-seco-lignans (1, 2), three new lignan glycosides (3, 4a, 4b), and 10 known lignans (5-14) were isolated from the fruit of Schisandra glaucescens Diels. The absolute configurations of 1 and 2 were determined by comparing their experimental and calculated electronic circular dichroism spectra. The molecular structures of the new compounds (3, 4a, and 4b), including their absolute configurations, were determined using various spectroscopic methods and hydrolysis reactions.

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Two new alkaloids, lycosprenine (1) and 2α-methoxy-6-O-methyllycorenine (2), along with 22 known alkaloids (3-23b), were isolated from the bulb of Lycoris sprengeri. Their structures were elucidated on the basis of spectral analysis and by comparison of the spectroscopic data with those of known compounds. Selected compounds (1-3 and 6-9) were tested for their neuroprotective activities against H2O2-, CoCl2- and Aβ25-35-induced SH-SY5Y cell injury, most of which exhibited neuroprotective effects of different degrees.

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Article Synopsis
  • Three new alkaloids and one new phenolic compound were extracted from the bulbs of the Lycoris aurea plant in Hunan Province, China.
  • Their chemical structures were determined using various spectroscopic techniques such as HRESIMS, UV, IR, and NMR.
  • The isolated compounds were tested for neuroprotective properties, with several showing significant protective effects against cell death induced by CoCl2 and H2O2 in SH-SY5Y cells.
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Three new alkaloids (1-3) and one new phenolic glycoside (4), together with twenty five known alkaloids (5-29), were isolated from the bulbs of Lycoris radiata collected from Huaihua county of Hunan province, China. Their structures were elucidated on the basis of comprehensive NMR and MS spectroscopic analysis. The isolated alkaloids were evaluated for their neuroprotective activities against CoCl2, H2O2 and Aβ(25-35)-induced SH-SY5Y cell injuries.

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In order to discover anticancer agents from natural sources, an ethanol-soluble extract of the root bark of Juglans cathayensis was investigated and showed cytotoxic effects against various human cancer cell lines. A subsequent phytochemical study on the EtOAc-soluble fraction determined 2-methoxyjuglone (1) as one of the main active constituents. Compound 1 was shown to be cytotoxic against HepG2 cells.

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Two new tetrahydrofuran lignans, schiglaucin A and B (1-2), together with eight known analogues (3-10), were isolated from the stems of Schisandra glaucescens Diels. Their structures were elucidated on the basis of spectroscopic techniques (HRESIMS, UV, IR, NMR, and CD experiments). All of the compounds were tested for their neuroprotective activities against H₂O₂- and CoCl₂-induced cell injuries in SH-SY5Y cells, respectively.

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Phytochemical investigations of the root bark of Juglans cathayensis DODE. led to the isolation of three new naphthalenyl glycosides, Jugnaphthalenoside A-C (1-3). Their structures were elucidated on the basis of extensive analysis of spectroscopic data.

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Schiglautone A (1), a unique 6/7/9-fused tricyclic carbon backbone triterpenoid, was isolated from the stems of Schisandra glaucescens. Its structure was determined on the basis of spectroscopic analysis and single-crystal X-ray crystallography. A hypothetical biosynthetic pathway of 1 was postulated.

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