Publications by authors named "Dong-ping Chen"

A refined synthesis of 1,4,2-diazaphospholidine-3,5-dione derivatives was achieved through a cyclization reaction involving Na(OCP) and isocyanates. Na(OCP) was demonstrated to be a relatively stable and safe source of phosphorus, enabling the production of diverse 1,4,2-diazaphospholidine-3,5-dione derivatives with high yields. The reaction proceeds efficiently under catalyst-free and mild conditions.

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A photocatalytic hydroamidomethylation of azobenzenes with ,-dimethylamides has been developed. Using tetrabutylammonium decatungstate (TBADT) as a photocatalyst, an array of azobenzenes and ,-dimethylamides reacted smoothly under visible light irradiation, affording previously unreported -amidomethyl-,'-diarylhydrazines in generally high yields. Mechanistic studies indicate that the reaction is enabled by TBADT-mediated hydrogen atom transfer (HAT) photocatalysis.

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Article Synopsis
  • A new method has been developed for synthesizing azaspirocyclic compounds using visible light, starting from -benzylacrylamides and alkyl chlorooxoacetates.
  • The process involves a series of reactions including free radical addition, cyclization, and dearomatization, allowing for efficient creation of important derivatives and ester groups in one step.
  • This technique shows versatility with various substrates and is able to handle different functional groups effectively, highlighting its efficiency in building complex molecules.
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  • The article DOI: 10.3892/ol.2017.7552 has been officially retracted.* -
  • This means that the findings or conclusions presented in the article are no longer considered valid.* -
  • Retractions typically occur due to issues such as errors in the research, ethical concerns, or validity problems.*
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This study investigates the formation of atmospheric molecular clusters containing ammonia (NH, A), methylamine (CHNH, MA), or dimethylamine (CHNHCH, DMA) with nitric acid (HNO, NA) using quantum mechanics. The Atmospheric Cluster Dynamic Code (ACDC) was employed to simulate the total evaporation rate, formation rate, and growth pathways of three types of clusters under dry and hydrated conditions. This study evaluates the enhancing potential of A/MA/DMA for NA-based new particle formation (NPF) at parts per trillion (ppt) levels.

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Multicomponent radical tandem reactions have emerged as a crucial technique for synthesizing complex molecules in organic chemistry. In this study, we report a palladium-catalyzed four-component difluoroalkylative carbonylation of enynes and ethyl difluoroiodoacetate. This transformation proceeds through a multistep sequential reaction that introduces reactive difluoro and carbonyl groups while constructing the benzofuran skeleton.

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The Narasaka-Heck reaction is one of the most straightforward methods for constructing pyrroline derivatives. Herein, we report a novel nickel-catalyzed three-component carbonylation reaction, which cleverly realizes the continuous construction of C(sp)-N bonds and C(sp)-C(sp) bonds and effectively promotes the synthesis of acyl-substituted pyrroline derivatives. Furthermore, this strategy not only expands the conversion pathway of γ,δ-unsaturated oxime esters but also provides a new method for the synthesis of nitrogen-containing heterocyclic compounds.

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Article Synopsis
  • The study aimed to analyze the failure patterns and prognostic factors for patients with nonmetastatic nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiotherapy (IMRT) from 2012 to 2016.
  • Among 847 patients, survival rates were high with 5-year local relapse-free survival at 94.3% and overall survival at 85.7%, although distant metastasis was identified as a major failure pattern.
  • The most significant prognostic factor was the TNM stage, with common complications being acute events like leukopenia and ongoing issues like xerostomia and hearing impairment.
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This study investigated the effects of modified Fangji Huangqi Decoction on the expression of proteins related to epithelial-mesenchymal transition(EMT) in a mouse model of unilateral ureteral obstruction( UUO) and in a rat renal tubular epithelial cell(NRK-52E) model of fibrosis induced by transforming growth factor β1(TGF-β1). It aims to decipher the molecular mechanism by which modified Fangji Huangqi Decoction alleviates renal interstitial fibrosis. C57/BL mice were subjected to UUO.

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An efficient [3 + 2] cycloaddition reaction between generated nitrile imines from hydrazonoyl halides and vinylsulfonium salts is developed. The nitrile imines are demonstrated to be a new class of reaction partner for vinylsulfonium salts to conduct the [3 + 2] cycloaddition reaction. The process provides a concise and efficient method for the construction of pyrazole derivatives under mild reaction conditions with broad substrate scope, good product yields, and high regioselectivity.

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We have successfully synthesized a series of bidentate ligands by utilizing 2-(trimethylsilyl)phenyl trifluorosulfonate as a precursor for the benzyl group. This method proceeded by inserting a polythiourea into the C═S π-bond, intramolecular ring proton migration, and ring opening. Salient features of this strategy are mild reaction conditions, a novel product structure, excellent stereochemistry, and a good functional group tolerance.

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A novel three-component cyclization carbonylation reaction of iodoarene-tethered propargyl ethers with amine and CO is reported. This palladium-catalyzed cascade reaction undergoes a sequence of oxidative addition, unsaturated bond migration, carbonyl insertion, and nucleophilic attack to deliver the benzofuran skeleton. Both aromatic amines and aliphatic amines could proceed smoothly in this transformation under one atm of CO.

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The interactions of the micro-mechanism of hydroxymethanesulfonic acid (HMSA) with the typical small organic molecule in atmospheric (X = methanol, formaldehyde, formic acid, methyl formate, dimethyl ether, acetone) has been investigated by density functional theory (DFT), quantum theory of atoms in molecules (QTAIM), Generalized Kohn-Sham Enery Decomposition Analysis (GKS-EDA) and the atmospheric clusters dynamic code (ACDC). The results of DFT show that the stable six- to eight-membered ring structures are easily formed in HMSA-X clusters. According to the topological analysis results of the AIM theory and the IRI method, a strong hydrogen bonding interaction is present in the complex.

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-Acylhydroxylamine has been widely employed as an electrophilic amination reagent in transition-metal-catalyzed C-N coupling reactions, but its use as an electrophilic oxygen source has not been disclosed. Here, we report a Pd-catalyzed 1,2-oxyarylation of alkenes with -acylhydroxylamines as an oxidant and an oxygen source for the first time. With simple amide as the monodentate directing group, this method features a broad substrate scope, good functional group tolerance, and mild conditions.

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We introduce switchable chemoselectivity strategies based on the hydrazone phosphaketene intermediate to synthesize three classes of 1,2,4-diazaphosphol derivatives. First, the five-membered heterocyclic P and O anion intermediates acted as nucleophilic agents in the selective construction of C-P and C-O bonds. Second, the phosphinidene served as a phosphorus synthon, allowing for the formation of C-P and C-N bonds.

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Background And Aims: HBV infection is a major etiology of acute-on-chronic liver failure (ACLF). At present, the pattern and regulation of hepatocyte death during HBV-ACLF progression are still undefined. Evaluating the mode of cell death and its inducers will provide new insights for developing therapeutic strategies targeting cell death.

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Whether and how tumor intrinsic signature determines macrophage-elicited metastasis remain elusive. Here, we show, in detailed studies of data regarding 7,477 patients of 20 types of human cancers, that only 13.8% ± 2.

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Di- and multinuclear hafnium complexes bridged by ligands have been rarely reported. In this article, a novel 3,5-disubstituted pyrazolate-bridged ligand LH with two [N N] -type chelating side arms was designed and synthesized, which supported a series of dinuclear hafnium complexes. Dinuclear hafnium azides [LHf (μ-1,1-N ) (N ) ][Na(THF) ] 3 and [LHf (μ-1,1-N ) (N ) ][Na(2,2,2-Kryptofix)] 4 were further synthesized and structurally characterized, featuring two sets of terminal and bridging azido ligands like jellyfishes.

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The purpose of this study was to investigate the effect of notoginsenoside R_1(NGR_1) on alleviating kidney injury by regulating renal oxidative stress and the Nrf2/HO-1 signaling pathway in mice with IgA nephropathy(IgAN) and its mechanism. The mouse model of IgAN was established using a variety of techniques, including continuous bovine serum albumin(BSA) gavage, subcutaneous injections of carbon tetrachloride(CCl_4) castor oil, and tail vein injections of lipopolysaccharide(LPS). After successful modeling, mice with IgAN were randomly separated into a model group, low, medium, and high-dose NGR_1 groups, and a losartan group, and C57BL6 mice were utilized as normal controls.

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Background: Patients with N2-3 nasopharyngeal carcinoma have a high risk of treatment being unsuccessful despite the current practice of using a concurrent adjuvant cisplatin-fluorouracil regimen. We aimed to compare the efficacy and safety of concurrent adjuvant cisplatin-gemcitabine with cisplatin-fluorouracil in N2-3 nasopharyngeal carcinoma.

Methods: We conducted an open-label, randomised, controlled, phase 3 trial at four cancer centres in China.

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We report a highly regioselective three-component coupling reaction of styrene, CO gas, and an amine compound to synthesize multisubstituted α,β-unsaturated amides, which involves a palladium-catalyzed sequential 1,4-palladium migration, C(sp)-H activation, carbonylation, and amination. Salient features of this strategy include the use of 1 atm of CO, excellent stereochemistry, and good functional group tolerance. Further, a series of control experiments and density functional theory calculations were performed to afford some insights for the transfer mechanism.

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A novel and efficient method for the catalytic installation of a carbonyl group via remote radical coupling is disclosed. The nickel-catalyzed reaction proceeds to undergo a sequential single-electron transfer, 1,5-hydrogen atom transfer, and carbonyl insertion, thus providing the α-substituted ketone. Further, this reaction could be carried out smoothly under normal pressure and redox-neutral conditions, and demonstrated functional-group compatibility and excellent site-selectivity.

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Article Synopsis
  • This study aimed to compare the effectiveness and safety of hyperfractionated radiotherapy versus standard fractionation for patients with advanced recurrent nasopharyngeal carcinoma who previously received high-dose radiation.
  • From July 2015 to December 2019, 144 eligible patients were enrolled in a phase 3 trial, with equal random assignment to either treatment group (72 each).
  • The primary goals were to assess severe late complications and overall survival, with findings indicating that hyperfractionation might reduce late toxicity compared to standard approaches.
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