79 research outputs found

    Alkali-Induced Ring-Opening of 2‑Amidodihydrofuran and Manganese-Catalyzed Aerobic Dehydrogenation Annulation: Access to Functionalized Oxazole

    No full text
    A novel and efficient synthesis of functionalized oxazoles from 2-amidodihydrofurans has been achieved by alkali-induced intramolecular C–O bond cleavage and formation using air as a green oxidant. Moreover, these functionalized oxazoles could be readily transformed into the corresponding oxazole-substituted pyrazoles and 2<i>H</i>-azirines

    Alkali-Induced Ring-Opening of 2‑Amidodihydrofuran and Manganese-Catalyzed Aerobic Dehydrogenation Annulation: Access to Functionalized Oxazole

    No full text
    A novel and efficient synthesis of functionalized oxazoles from 2-amidodihydrofurans has been achieved by alkali-induced intramolecular C–O bond cleavage and formation using air as a green oxidant. Moreover, these functionalized oxazoles could be readily transformed into the corresponding oxazole-substituted pyrazoles and 2<i>H</i>-azirines

    Direct Oxidative Coupling of Enamides and 1,3-Dicarbonyl Compounds: A Facile and Versatile Approach to Dihydrofurans, Furans, Pyrroles, and Dicarbonyl Enamides

    No full text
    An efficient manganese­(III)-mediated oxidative coupling reaction between α-aryl enamides and 1,3-dicarbonyl compounds has been developed. A series of dihydrofurans and dicarbonyl enamides were synthesized in moderate to good yields. Moreover, these dihydrofurans could be readily transformed into the corresponding furans and pyrroles via the Paal–Knorr reaction

    Effects of emodin on ERK1/2 and p38 phosphorylation and PPARγ expression in the thoracic aorta of hyperhomocysteinemic rats.

    No full text
    <p>Rats were fed with the high methionine diet for 4 weeks, and simultaneously treated with two doses of emodin. In the end of the experiment, the thoracic aorta was removed for detecting ERK1/2 and p38 phosphorylation as well as PPARγ protein expression with Western blot. Data were expressed as mean ± S.E.M. (n = 8). *P < 0.05 vs. control, #P < 0.05 vs. model group.</p

    Effect of emodin on the viability of VSMCs.

    No full text
    <p>The cells were incubated with the different concentrations of emodin for 24 h. Then, the cell viability was assayed by the MTT method. DMSO (0.1%) was used as solvent control. Results from three independent experiments were expressed as mean ± S.E.M. *<i>P</i> < 0.05 <i>vs</i>. DMSO.</p

    Effects of emodin on the serum Hcy and CRP levels and CRP expression in the thoracic aorta in hyperhomocysteinemic rats.

    No full text
    <p>Rats were fed with the high methionine diet for 4 weeks, and simultaneously treated with two doses of emodin. In the end of the experiment, the blood was collected for detecting serum Hcy level (A) with the enzyme cycling method and CRP concentration (B) with ELISA. Then, the thoracic aorta was removed for examining mRNA (C) and protein (D) expression of CRP by RT-PCR and Western blot, respectively. Data were expressed as mean ± S.E.M. (n = 8). *<i>P</i> < 0.05 <i>vs</i>. control, #<i>P</i> < 0.05 <i>vs</i>. model group.</p

    Quantitative Label-Free and Real-Time Surface-Enhanced Raman Scattering Monitoring of Reaction Kinetics Using Self-Assembled Bifunctional Nanoparticle Arrays

    No full text
    Although surface-enhanced Raman scattering (SERS) has proven to be an effective tool for label-free monitoring of catalytic reactions, quantitative characterization of reaction kinetics via this technique remains challenging owing to the difficulty in integrating catalytic and plasmonic activities into a single platform. In this work, we report on an easy access to highly sensitive plasmonic nanoarrays for direct and label-free monitoring of a gold-catalyzed reaction by SERS. The hierarchically structured three-dimensional assemblies, which consist of small gold catalyst nanoparticles distributed on a self-assembled monolayer of larger gold nanoparticles, were formed through a simple and rapid stepwise interfacial self-assembling process (fabrication time <10 min). The well-defined interparticle distances (<1 nm) lead to efficient plasmonic coupling and ensure both catalytic and SERS-active sites exposed to the environment. Such a versatile bifunctional platform thus allows quantitative determination of the rate constant and activation energy of the catalytic reaction with SERS

    Effects of emodin on Hcy-stimulated CRP expression and ROS generation in VSMCs.

    No full text
    <p>The cells were preincubated with the different concentrations of emodin for 24 h before stimulation with 100 μM homocysteine (Hcy) for 12 h. mRNA (A) and protein (B) expression of CRP was identified by RT-PCR and Western blot, respectively. In another experiment, the cells were incubated with the different concentrations of emodin for 24 h and then, exposed to 100 μM Hcy for 40 min after preloaded with H<sub>2</sub>DCF-DA (10 μM) for 30 min. The fluorescent intensity was measured by a fluorescence microscope. (C) Representative fluorescence images: (a) control, (b) Hcy alone, (c) Hcy + 0.1 μM emodin, (d) Hcy + 1 μM emodin, (e) Hcy + 10 μM emodin, (f) 10 μM emodin, (g) 0.1% DMSO. (D) Relative fluorescence intensity quantified from the fluorescence images. Emodin alone was used as drug control and DMSO (0.1%) was used as solvent control. Results from three independent experiments were expressed as means ± S.E.M. *<i>P</i> < 0.05 <i>vs</i>. control, <sup><i>#</i></sup><i>P</i> < 0.05 <i>vs</i>. Hcy alone.</p

    Synthesis of Substituted 1<i>H</i>-Indazoles from Arynes and Hydrazones

    No full text
    The 1<i>H</i>-indazole skeleton can be constructed by a [3 + 2] annulation approach from arynes and hydrazones. Under different reaction conditions, both <i>N</i>-tosylhydrazones and <i>N</i>-aryl/alkylhydrazones can be used to afford a variety of indazoles. The former reaction affords 3-substituted indazoles either via <i>in situ</i> generated diazo compounds or through an annulation/elimination process. The latter reaction leads to 1,3-disubstituted indazoles likely through an annulation/oxidation process. The reactions operate under mild conditions and can accommodate aryl, vinyl, and less satisfactorily, alkyl groups

    Hfq regulates outer membrane protein expression.

    No full text
    <p><b>A.</b> Relative expression of OMP genes in derivative strains compared to WT. Relative expression (normalized to the WT level for each gene) was determined by qPCR as described in Materials and Methods. Error bars correspond to standard deviations from three biological replicates. Statistically significant differences are indicated (*<i>p</i> < 0.05, **<i>p</i> < 0.01, ***<i>p</i> <0.001). <b>B</b>. SDS-PAGE analysis of the outer membrane fraction from ZJ-T, <i>Δhfq</i>-T and <i>hfq</i><sup>+</sup>-T. M: Molecular size markers. Apparent sizes of markers are indicated on the left. The positions of two bands that increase in the <i>hfq</i> mutant are indicated by stars.</p
    corecore