Yuguo Du

Jiangxi Normal University, Nan-ch’ang-shih, Jiangxi Sheng, China

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Publications (132)315.12 Total impact

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    ABSTRACT: Thioglycoside-containing trimannose analogs were designed and prepared to mimic the natural N-glycan core trisaccharide α-d-Man-(1→3)-[α-d-Man-(1→6)]-d-Man. (1→6)-S-Linked trimannoside 1 and its trivalent cluster 2 were synthesized in 11 and 15 steps, respectively, taking advantages of the armed mannopyranosyl trichloroacetimidate as glycosyl donor. Hemagglutination inhibition of the two new thiomannotriose analogs was preliminarily examined. Comparing to the parent trimannoside α-d-Man-(1→3)-[α-d-Man-(1→6)]-d-Man-OMe, the cluster mannotrioside 2 presented a comparable binding affinity to Con A, while the monomer 6-S-trimannoside 1 exhibited a slightly lower inhibition ability. Copyright © 2015 Elsevier Ltd. All rights reserved.
    Carbohydrate research 05/2015; 412:56-65. DOI:10.1016/j.carres.2015.05.001 · 1.97 Impact Factor
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    ABSTRACT: NKT cells, a unique subset of T cells that recognizes glycolipid antigens presented by CD1d molecules, are believed to produce key cytokines of both Th1 and Th2 T cells and are thus involved in the control of several types of immune response. As an active glycolipid antigen having α-galactosyl ceramide core structure, KRN7000 showed promising immunostimulation activity and was selected as an anticancer drug candidate for further clinical application. In this report, three new KRN7000 structural analogues were designed and synthesized, in which the ring oxygen of the galactopyranose residue is replaced by a sulfur atom along with the variation on the lipid chain. Their abilities for stimulating mouse NKT cells to produce IFN-γ and IL-4 were evaluated both in vivo and in vitro.
    ACS Medicinal Chemistry Letters 04/2015; 6(4):476-80. DOI:10.1021/acsmedchemlett.5b00046 · 3.07 Impact Factor
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    ABSTRACT: An efficient total synthesis toward spiroketal diastereomers of cephalosporolides H and I was achieved, respectively, taking advantage of intramolecular Wacker-type spiroketalization on the common olefin-containing dihydroxy-γ-lactone substrate. By comparing the physical data of natural products with synthetic samples, we suggest that the reported stereochemical assignments for cephalosporolides H and I are incorrect. Our work suggests that the stereochemistry on C-6 of the core spiroketal skeleton should be revised to S from its original R assignment, and the real structures of these natural compounds should be reconsidered.
    Tetrahedron 04/2015; 71(23). DOI:10.1016/j.tet.2015.04.025 · 2.82 Impact Factor
  • ChemInform 04/2015; 46(16). DOI:10.1002/chin.201516297
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    ABSTRACT: A concise total synthesis of natural product bacillamide B was accomplished in 30% overall yield starting from L-Cystine. The key step was a one-pot four-step process of thiazoline formation via a cascade disulfide cleavage/thiocarbonylation/ Staudinger reduction/aza-Wittig reaction using β-azido disulfide and carboxylic acid as substrates. The absolute configuration of the natural bacillamide B was reconfirmed to be S and the specific optical rotation should be revised to (-).
    Organic & Biomolecular Chemistry 02/2015; 13(14). DOI:10.1039/C5OB00093A · 3.49 Impact Factor
  • ChemInform 02/2015; 46(5). DOI:10.1002/chin.201505216
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    ABSTRACT: The different toxicity characteristics of arsenic species result in discrepant ecological risk. The predicted no-effect concentrations (PNECs) 43.65, 250.18, and 2.00×10(3)μg/L were calculated for As(III), As(V), and dimethylarsinic acid in aqueous phase, respectively. With these PNECs, the ecological risk from arsenic species in Pearl River Delta in China and Kwabrafo stream in Ghana was evaluated. It was found that the risk from As(III) and As(V) in the samples from Pearl River Delta was low, while much high in Kwabrafo stream. This study implies that ecological risk of arsenic should be evaluated basing on its species. Copyright © 2014. Published by Elsevier B.V.
    Journal of Environmental Sciences 01/2015; 27. DOI:10.1016/j.jes.2014.03.006 · 1.92 Impact Factor
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    ABSTRACT: Tetrabromobisphenol A mono(2-hydroxyethyl ether) (TBBPA-MHEE) and TBBPA mono(glycidyl ether) (TBBPA-MGE), two impurities of TBBPA derivatives, were hypothesized to be novel brominated contaminants with potential toxicity. However, due to lacking of analytical method and pure standards, their environmental behavior and toxicity have not been studied. Herein we developed a sensitive method based on ultra-high performance liquid chromatography-Orbitrap Fusion Tribrid mass spectrometer (UHPLC-Orbitrap Fusion TMS) for simultaneous detection of TBBPA-MHEE and TBBPA-MGE in water samples. The sample pretreatment method and the experimental conditions of UHPLC and Orbitrap Fusion TMS, were optimized in detail. The instrument detection limits (IDLs) for TBBPA-MHEE and TBBPA-MGE were 0.5pg and 0.6pg, respectively. The method detection limits (MDLs) for TBBPA-MHEE and TBBPA-MGE in river water samples were 0.9 and 0.8ng/L. With the proposed method, we were able to detect TBBPA-MHEE and TBBPA-MGE for the first time in water samples and technical products of TBBPA derivatives. Therefore, UHPLC-Orbitrap Fusion TMS is a simple and effective tool for identification and quantification of novel contaminants in the environment. Copyright © 2014 Elsevier B.V. All rights reserved.
    Journal of Chromatography A 12/2014; 1377. DOI:10.1016/j.chroma.2014.12.038 · 4.26 Impact Factor
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    ABSTRACT: The brominated products, formed in chlorination treatment of benzophenone-4 in the presence of bromide ions, were identified, and the formation pathways were proposed. Under disinfection conditions, benzophenone-4 would undertake electrophilic substitution generating mono- or di-halogenated products, which would be oxidized to esters and further hydrolyzed to phenol derivatives. The generated catechol intermediate would be transformed into furan-like heterocyclic product. The product species were pH-dependent, while benzophenone-4 elimination was chlorine dose-dependent. When the chlorination treatment was performed on ambient water spiked with benzophenone-4 and bromide ions, most of brominated byproducts could be detected, and the acute toxicity significantly increased as well. Copyright © 2014. Published by Elsevier B.V.
    Journal of Environmental Sciences 12/2014; 26(12). DOI:10.1016/j.jes.2014.03.001 · 1.92 Impact Factor
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    ABSTRACT: Mercury (Hg) exists in different chemical forms presenting varied toxic potentials. It is necessary to explore an ecological risk assessment method for different mercury species in aquatic environment. The predicted no-effect concentrations (PNECs) for Hg(II) and methyl mercury (MeHg) in the aqueous phase, calculated using the species sensitivity distribution method and the assessment factor method, were 0.39 and 6.5 × 10− 3 μg/L, respectively. The partition theory of Hg between sediment and aqueous phases was considered, along with PNECs for the aqueous phase to conduct an ecological risk assessment for Hg in the sediment phase. Two case studies, one in China and one in the Western Black Sea, were conducted using these PNECs. The toxicity of mercury is heavily dependent on their forms, and their potential ecological risk should be respectively evaluated on the basis of mercury species.
    Journal of Environmental Sciences 11/2014; 28. DOI:10.1016/j.jes.2014.06.042 · 1.92 Impact Factor
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    ABSTRACT: (-)-Petrosiol E, a metabolite of sponge Petrosia strongylata, has been synthesized in 32% overall yield from cheap natural D-xylose in 10 steps. Our strategy provides an efficient way for the total synthesis of other petrosiol members, featuring the three contiguous stereogenic centers are easily constructed from D-xylose chiral template.
    Tetrahedron 11/2014; 70(44):8231–8235. DOI:10.1016/j.tet.2014.09.030 · 2.82 Impact Factor
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    ABSTRACT: A large quantity of toxic chemical pollutants possibly remains in reclaimed water due to the limited removal efficiency in traditional reclamation processes. It is not enough to guarantee the safety of reclaimed water using conventional water quality criteria. An integrated assessment method based on toxicity test is necessary to vividly depict the safety of reclaimed water for reuse. A toxicity test battery consisting of lethality, genotoxicity and endocrine disrupting effect was designed to screen the multiple biological effects of residual toxic chemicals in reclaimed water. The toxicity results of reclaimed water were converted into the equivalent concentrations of the corresponding positive reference substances (EQC). Simultaneously, the predicted no-effect concentration (PNEC) of each positive reference substance was obtained by analyzing the species sensitivity distribution (SSD) of toxicity data. An index “toxicity score” was proposed and valued as 1, 2, 3, or 4 depending on the ratio of the corresponding EQC to PNEC. For vividly ranking the safety of reclaimed water, an integrated assessment index “toxicity rank” was proposed, which was classified into A, B, C, or D rank with A being the safest. The proposed method was proved to be effective in evaluating reclaimed water samples in case studies.
    Journal of Environmental Sciences 10/2014; 26(10). DOI:10.1016/j.jes.2014.07.008 · 1.92 Impact Factor
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    ABSTRACT: The stereoselective synthesis of the title compound (I) from L-arabinose is reported.
    ChemInform 09/2014; 45(35). DOI:10.1002/chin.201435218
  • Min Li, Dongbin Wei, Yuguo Du
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    ABSTRACT: Acute toxicity of 21 quinolone antibiotics was monitored using photobacterium Vibrio fischeri assay. The minimum IC20 (inhibitory concentration for 20% luminescence elimination) was obtained at the least 18.86 μmol/L for the tested quinolones. A quantitative structure–activity relationship model was established to investigate the possible mechanism for the acute toxicity. The critical physicochemical descriptors, describing σ and π atom electronegativity, implied that the electron transfer might occur between the quinolones and photobacterium V. fischeri. Although the quinolones exhibited limited acute toxicity to photobacterium, toxicity elevation was detected after their chlorination. Hence, chlorination disinfection treatment of quinolone-containing water should be of concerns.
    Journal of Environmental Sciences 09/2014; 26(9). DOI:10.1016/j.jes.2014.06.023 · 1.92 Impact Factor
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    ABSTRACT: A novel and efficient method for one-pot synthesis of 2,4-disubstituted thiazoles from carboxylic acids or anhydrides is established. Based on this new methodology, the total synthesis of bis-2,4-disubstituted bis(thiazoles) natural product Cystothiazole C is also presented.
    Organic & Biomolecular Chemistry 08/2014; 12(42). DOI:10.1039/C4OB01460J · 3.49 Impact Factor
  • Chaoli Zhang, Jun Liu, Yuguo Du
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    ABSTRACT: The target compound is synthesized in 11 steps with 22% overall yield.
    ChemInform 07/2014; 45(28). DOI:10.1002/chin.201428218
  • Yuan Li, Dongbin Wei, Yuguo Du
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    ABSTRACT: The characteristics of the oxidative transformation of the antibiotic levofloxacin (abbreviated as LEV) by manganese oxide were investigated. Up to 91% of LEV were removed with an equivalent of 200units (abbreviated as equiv) of manganese oxide within a 35-day treatment period. A total of ten transformation products were identified, and five of them were newly reported. A tentative transformation pathway of LEV in the manganese oxide system involving oxidation and dealkylation was proposed. In addition, the variation in the genotoxicity and antibacterial activity along with the treatment by manganese oxide were traced using a SOS/umu assay and Escherichia coli growth inhibition assay, respectively. The results indicated that the genotoxicity significantly decreased in response to treatment with manganese oxide, while the antibacterial activity was not markedly affected until 160-equiv of δ-MnO2 were added. This study suggests that the oxidative degradation of LEV by manganese oxide can play an important role in the natural attenuation of LEV in sediment or soil matrices. The transformation reaction may be further optimized for removing quinolone antibiotics from wastewater or other environmental matrices to reduce the potential risk.
    Chemosphere 07/2014; 119C:282-288. DOI:10.1016/j.chemosphere.2014.06.064 · 3.50 Impact Factor
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    ABSTRACT: 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and polychlorinated biphenyls (PCBs) are persistent organic pollutants which coexist in environment, and human are co-exposed to these chemicals. Our present study was aimed to investigate the possible enhanced nonalcoholic fatty liver disease (NAFLD) in ApoE−/− mice co-exposed to TCDD and PCBs and to reveal the potential mechanisms involved in. Male ApoE−/− mice were exposed to TCDD (15 μg/kg) and Aroclor1254 (55 mg/kg, a representative mixture of PCBs) alone or in combination by intraperitoneal injection four times over a 6-week period. Those mice co-exposed to PCBs and TCDD developed serious liver steatosis, necrosis, and inflammatory stimuli. Interestingly, all treatment induced hepatic cytochrome P450 1A1 (CYP1A1) expression, but the maximal level of CYP1A1 was not observed in the co-exposure group. Furthermore, microarray analysis by ingenuity pathway analysis software showed that the nuclear factor-erythroid 2-related factor 2 (Nrf2)-mediated oxidative stress response pathway was significantly activated following co-exposure to TCDD and PCBs. Our data demonstrated that co-exposure to TCDD and PCBs markedly worsen NAFLD in ApoE−/− mice. © 2014 Wiley Periodicals, Inc. Environ Toxicol, 2014.
    Environmental Toxicology 05/2014; DOI:10.1002/tox.22006 · 2.56 Impact Factor
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    ABSTRACT: A convergent and stereoselective synthesis of cochliomycin A, a 14-membered resorcyclic acid lactone, based on chiron approach is described. The key reactions involved olefin cross-metathesis and sodium hydride promoted one-pot intramolecular lactonization. L-Arabinose was used as a chiral pool material for the construction of the key fragment.
    Tetrahedron 04/2014; 70(16):2616–2620. DOI:10.1016/j.tet.2014.03.001 · 2.82 Impact Factor
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    ABSTRACT: 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and polychlorinated biphenyls (PCBs) are persistent organic pollutants found as complex mixtures in the environment throughout the world. Therefore, humans are ubiquitously and simultaneously exposed to TCDD and PCBs. TCDD and PCBs alone have been linked to atherosclerosis. However, the effects of interactions or synergism between TCDD and PCBs on atherogenesis are unknown. We investigated the possible enhanced atherogenesis by co-exposure to TCDD and PCBs and the potential mechanism(s) involved in this enhancement. Male apoE −/− mice were exposed to TCDD (15 μg/kg) and Aroclor1254 (55 mg/kg, a representative mixture of PCBs) alone or in combination by intraperitoneal injection four times over six weeks of duration. Our results showed that mice exposed to TCDD alone, but not Aroclor1254 alone, developed atherosclerotic lesions. Moreover, we found that atherosclerotic disease was exacerbated to the greatest extent in mice co-exposed to TCDD and Aroclor1254. The enhanced lesions correlated with several pro-atherogenic changes, including a marked increase in the accumulation of the platelet-derived chemokine PF4, and the expression of the proinflammatory cytokine MCP-1 and the critical immunity gene-RIG-I. Our data demonstrated that co-exposure to TCDD and Aroclor1254 markedly enhanced atherogenesis in apoE −/− mice. Significantly, our observations suggest that combined exposure to TCDD and PCBs may be a greater cardiovascular health risk than previously anticipated from individual studies.
    Toxicology and Applied Pharmacology 04/2014; DOI:10.1016/j.taap.2014.02.007 · 3.63 Impact Factor

Publication Stats

933 Citations
315.12 Total Impact Points

Institutions

  • 2015
    • Jiangxi Normal University
      Nan-ch’ang-shih, Jiangxi Sheng, China
  • 2001–2015
    • Chinese Academy of Sciences
      • • State Key Laboratory of Environmental Chemistry and Ecotoxicology
      • • Research Center for Eco-Environmental Sciences
      Peping, Beijing, China
  • 2010–2014
    • Technical Institute of Physics and Chemistry
      Peping, Beijing, China
  • 2009
    • Chinese Research Academy of Environmental Sciences
      Peping, Beijing, China
    • Albany Medical College
      • Center for Immunology and Microbial Disease
      Albany, New York, United States
  • 2004
    • Rensselaer Polytechnic Institute
      Троя, New York, United States
  • 2000–2002
    • Academia Sinica
      T’ai-pei, Taipei, Taiwan