Publications by authors named "Duo-Zhi Chen"

The persistent mutation of the novel coronavirus presents a continual threat of infections and associated illnesses. While considerable research efforts have concentrated on the functional proteins of SARS-CoV-2 in the development of anti-COVID-19 therapeutics, the structural proteins, particularly the N protein, have received comparatively less attention. This study focuses on the N protein, a critical structural component of the virus, and employs advanced deep learning models, including EMPIRE and DeepFrag, to optimize the structures of phenanthridine-based compounds.

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Article Synopsis
  • The study investigates the antiviral properties of the herb Steud, traditionally used in Chinese medicine, focusing on its effectiveness against COVID-19, which has not been extensively studied.
  • Researchers successfully isolated nine new compounds from Steud, with one particular compound (Compound 1) showing significant antiviral activity by directly binding to the RNA-dependent RNA polymerase of the virus, crucial for its replication.
  • The findings enhance the understanding of the antiviral properties of Steud and suggest potential for using atisane-type diterpenoid compounds as new antiviral agents in the fight against COVID-19.
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  • * The structures of these steroids were determined using various analytical techniques like HRESIMS, NMR, UV, and IR.
  • * The study tested the antiviral activity of these compounds, revealing that they have different levels of inhibition against the SARS-CoV-2 main protease at a concentration of 200 μM.
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Daphmacrimines A-K (1-11) were isolated from the leaves and stems of Daphniphyllum macropodum Miq. Their structures and stereochemistries were determined by extensive techniques, including HRESIMS, NMR, ECD, IR, and single-crystal X-ray crystallography. Daphmacrimines A-D (1-4) are unprecedented Daphniphyllum alkaloids with a 2-oxazolidinone ring.

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Five new toosendanin limonoids with highly oxidative furan ring walsurobustones A-D (1-4), and one new furan ring degraded limonoid walsurobustone E (5) together with one known compound toonapubesic acid B (6) were isolated from the leaves of Walsura robusta. Their structures were elucidated by NMR and MS data. Especially, the absolute configuration of toonapubesic acid B (6) was confirmed by X-ray diffraction study.

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Humans have been suffering from vitiligo for a long time. Target vitiligo drugs have yet been approved. Activation of Wnt/β-catenin signalling has potential in the therapeutic use of vitiligo, so exploring new drugs that specifically directly activate Wnt is worthwhile to obtain new anti-vitiligo agents.

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The COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is unprecedented in human history. As a major structural protein, nucleocapsid protein (NPro) is critical to the replication of SARS-CoV-2. In this work, 17 NPro-targeting phenanthridine derivatives were rationally designed and synthesized, based on the crystal structure of NPro.

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Two new cycloartane triterpenoids, (24 )-cycloartane-3,24,25,30-tetrol () and (24 )-24,25,30-trihydroxy-9,19-cycloartane-3-one (), along with three known compounds () were isolated from leaves and twigs of . The new compounds were elucidated based on comprehensive spectroscopic analysis, including 1 D, 2 D NMR and HREIMS. The in vitro cytotoxic activities evaluation of five human cancer cell lines revealed that compound exhibited cytotoxic activity on all of tested human cancer cell lines, while compound only had specific activity on SMMC-7721 cell line.

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Porcine epidemic diarrhea virus (PEDV) has become increasingly problematic around the world, not only for its hazards to livestock but also due to the possibility that it is a zoonotic disease. Although vaccine therapy has made some progress toward PEDV control, additional effective therapeutic strategies against PEDV are needed, such as the development of chemotherapeutic agents. The aim of this work was to identify novel anti-PEDV agents by designing and synthesizing a series of phenanthridine derivatives.

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Aphananoid A, a limonoid which features a rare C appendage and new 5/6/5 fused-ring framework, was obtained from . The planar structure as well as the absolute configuration was identified based on extensive spectroscopic analysis and electronic circular dichroism calculations. The biogenetic pathway of aphananoid A was also speculated, which arises from the triterpene by the 3,4--7,8--6,8 -7,30- key pattern.

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Six new diterpenes Euphonoids A-F including one ingenol (1), three lathyrane (2-5), one ent-abietane (6) and fifteen known derivatives (7-21) were isolated from the aerial parts of Euphorbia antiquorum L. Their structures were elucidated by physical data analysis. Compounds 1, 12, and 16 improve the melanogenesis in B16 cells in vitro.

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Two new sesquiterpenoids were isolated from Stellera chamaejasme L., known as the traditional Chinese herb 'Rui Xiang Lang Du'. The compounds were elucidated as stelleraguaianone B (1) and C (2) by comprehensive spectroscopic analysis, including 1D and 2D NMR as well as HRESIMS, and by comparing their NMR data with known compounds.

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Two new lignans (-), along with five known compounds (-) with different structures were isolated from leaves and twigs of Croizat. The new lignans were elucidated as (7'R,8'S)-3,3',5'-trimethoxy-4,4'-dihydroxy-7-en-7',9- epoxy-8,8'-lignan () and (7'R,8'S)-3,3'-dimethoxy-4,4'-dihydroxy-7-en-7',9-epoxy-8, 8'-lignan () by comprehensive spectroscopic analysis including 1D and 2D NMR as well as HREIMS and comparing their NMR data with known compounds in the literature. Among these isolated compounds, compound , , , and were tested for anti- inflammatory effects by inhibiting NO production in lipopolysaccharide (LPS)-stimulated RAW 264.

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Article Synopsis
  • HLY78 is the first agonist that activates the Wnt/β-catenin signaling pathway by targeting the DAX domain of axin, but its weak effect limits its use in pharmacological studies.
  • Researchers optimized HLY78 by designing and synthesizing 36 new derivatives, some of which demonstrated stronger Wnt activity than the original compound.
  • One notable derivative significantly outperformed HLY78, showing 10 times greater potency, while the structure-activity relationship (SAR) analysis highlighted that a pyrazole group at the C-8 position and a specific methyl substitution at C-4 enhance Wnt activation, while oxidation at C-6 diminishes it.
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Xiaojiang Hao, who obtained Master Degree from Kunming Institute of Botany (KIB), Chinese Academy of Sciences (CAS) in 1985, and Doctor in Pharmacy degree in Pharmacy from Institute for Chemical Research, Kyoto University, in 1990, was born in Chongqing in July, 1951. In 1991, he returned to KIB, CAS, as an Associate professor and served as the chair of the Department of Phytochemistry. In 1994, he was promoted to a full professor at the current institute.

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Two new 6-norpolycyclic polyprenylated acylphloroglucinols (PPAPs), hypermonins A (1) and B (2), featuring an undescribed decahydroindeno[1,7-bc]furan ring system, were isolated from the leaves and twigs of Hypericum monogynum. These compounds are a pair of epimers with opposite configurations at the C-5 position. Their structures, including their absolute configurations, were determined by extensive spectroscopic analysis and electronic circular dichroism (ECD) calculations.

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Fifteen known amaryllidaceae alkaloids were isolated from the bulbs of Lycoris radiata. Some of the compounds and lycoricidine derivatives had been screened for the activities against tobacco mosaic virus (TMV) by the conventional half-leaf method. Lycoricidine derivatives were also carried out the assay of effect on systemic infection of TMV by western-blot and RT-PCR analysis.

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Four new indole alkaloids, melodinusines A-D (1, 2, 6, and 7), along with 26 known indole alkaloids, were isolated from Melodinus tenuicaudatus and Melodinus khasianus (Melodinus genus). Among them, 1 and 2 are aspidospermine-aspidospermine-type bisindole alkaloids while 7 is a novel melodinus-type alkaloid. Their structures were established on the basis of comprehensive spectroscopic data analysis and the structure of 7 was further confirmed by single-crystal X-ray diffraction analysis.

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Rare ent-abietane-rosane diterpenoid heterodimers, Bisebracteolasins A and B (1 and 2, respectively), were isolated from the roots of Euphorbia ebracteolata Hayata. Their structures and absolute configurations were elucidated from spectroscopic data and X-ray diffraction analysis. Compounds 1 and 2 exhibited moderate cytotoxic effects against five cancer cell lines.

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(+)-Perforison A and (-)-perforison A, a new pair of chromone enantiomers, along with four known compounds, were isolated from the leaves and stems of Harrisonia perforata. Their structures and absolute configurations were determined on the basis of extensive analysis of spectroscopic data and electronic circular dichroism (ECD) calculations. The cytotoxic activities in vitro of these compounds were evaluated, but none showed significant activity.

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Four new Myrioneuron alkaloids, mysumamides A-D (1-4), along with three known ones were isolated from the twigs and leaves of Myrioneuron effusum. All of these alkaloids possessed the tetracyclic skeleton and contained the decahydroquinoline (cis-DHQ) moiety. Their structures and relative configurations were elucidated on the basis of spectroscopic methods, especially 2D NMR techniques.

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Lycorine is a benzylphenethylamine-type alkaloid member of the Amaryllidaceae family. A lycorine derivative, HLY78, was previously identified as a new Wnt/β-catenin signaling pathway agonist that targets the DAX domain of axin. Herein, the structural optimization of HLY78 and analyses of the structure-activity relationships of lycorine-derived phenanthridine derivatives as agonists of the Wnt/β-catenin signaling pathway are presented.

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Three new Myrioneuron alkaloids, myrifamines A-C (1-3), with unique skeletons were isolated from Myrioneuron faberi. The absolute configuration of 1 was confirmed by single-crystal X-ray diffraction analysis, and the stereochemistry of the other two alkaloids was determined using a combination of ROESY experiments and calculated and experimental electronic circular dichroism spectra. Myrifamine C (3) is the first example of a symmetric dimer among the Myrioneuron alkaloids.

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Fourteen new limonoids, munronins A-N (1-14), and eight known limonoids (15-22) were isolated from the whole plants of Munronia henryi. The structures of the new compounds were elucidated by 2D NMR spectroscopy and mass spectrometry, and the structure of 8 was confirmed by single-crystal X-ray diffraction analysis. Compound 1 represents the first limonoid found with a novel 7-oxabicyclo[2.

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Two new compounds, maniesculentins A (1) and B (6), together with four known ones were isolated from the stems of Manihot esculenta Crantz. The structures of the new compounds were elucidated by extensive spectroscopic methods including NMR spectroscopy and mass spectrometry. The two new compounds (1, 6) were assayed for antibacterial activity against four tested bacteria lines.

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