• Title/Summary/Keyword: Pyrrole

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Studies on the Preparation of Conducting Composite Film by a Vapor Phase in situ Polymerization (전도성 복합필름의 기상중합과 특성에 대한 연구)

  • Park, Jun-Seo;Park, Jang-Woo
    • Applied Chemistry for Engineering
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    • v.10 no.6
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    • pp.902-906
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    • 1999
  • Electrically conducting composite films were prepared by a vapor phase in situ polymerization of pyrrole in the methyl cellulose film containing a copper(II) perchlorate. Methylcellulose had high affinity to pyrrole and was used as a matrix polymer. Conducting polypyrrole was embedded in the methylcellulose film forming a conducting network and the conductivity of the composite films ranged $10^{-1}$ to $10^{-7}S/cm$. The conductivities of conducting composite films were dependent on the nature of the matrix polymers, concentration of oxidant and polymerization time. In situ polymerization of pyrrole was observed in the matrix polymer and confirmed by UV-vis spectra. From the results of the thermogravimetric analysis, the chemical oxidative polymerization of pyrrole in the matrix polymers did not give any negative effects on the thermal stability of the composite films. Electron micrograph of composites indicated good penetration of PPy in the matrix polymer. DMA suggested a certain degree of incompatibility of the polypyrrole in the composites.

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A Study on the Synthesis of Dipyrrolylbenzenes (Dipyrrolylbenzene들의 합성에 관한 연구)

  • 정대일;변석인;송현애;이도훈;김윤영;이용균;박유미;최순규;한정태
    • Journal of Life Science
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    • v.13 no.6
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    • pp.836-842
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    • 2003
  • 1-(2-Aminophenyl)pyrrole 5 was synthesized by using 1,2-phenylenediamine with 2,5-dimethoxy-tetrahydrofuran in glacial acetic acid. 1-(3-Aminophenyl)pyrrole 7 and 1,3-dipyrrolylbenzene 8 were obtained by using 1,3-phenylene-diamine with 2,5-dimethoxytetrahydrofuran in glacial acetic acid. 1,4-Dipyrrolylbenzene 10 was synthesized by using 1,4-phenylenediamine with 2,5-dimethoxy-tetrahydrofuran in glacial acetic acid. Aminophenylpyrroles 5, 7 and dipyrrolylbenzenes 8, 10 were respectively synthesized by treatment of 1,2-phenylenediamine, 1,3-phenylenediamine, 1,4-phenylene-diamine and 2,5-dimethoxytetrahydrofuran in (1) no solvent or (2) acrylic acid or (3) silica gel or (4) acrylic acid and silica gel or (5) silica gel and glacial acetic acid instead of glacial acetic acid. The best yield for dipyrrolylbenzene 10 was obtained when silica gel and glacial acetic acid was used. 9-Phenyl-carbazole 11 was synthesized by treatment of 1-phenylpyrrole with 2,5-dimethoxy-tetrahydrofuran in glacial acetic acid.

Selective Determination of Serotonin on Poly(3,4-ethylenedioxy pyrrole)-single-walled Carbon Nanotube-Modified Glassy Carbon Electrodes

  • Kim, Seul-Ki;Bae, Si-Ra;Ahmed, Mohammad Shamsuddin;You, Jung-Min;Jeon, Seung-Won
    • Bulletin of the Korean Chemical Society
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    • v.32 no.4
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    • pp.1215-1220
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    • 2011
  • An electrochemically-modified electrode [P(EDOP-SWNTs)/GCE] was prepared by electropolymerization of 3,4-ethylenedioxy pyrrole (EDOP) single-walled carbon nanotubes (SWNTs) on the surface of a glassy carbon electrode (GCE) and characterized by SEM, CV, and DPV. This modified electrode was employed as an electrochemical biosensor for the selective determination of serotonin concentrations at pH 7.4 and exhibited a typical enhanced effect on the current response of serotonin with a lower oxidation overpotential. The linear response was in the range of $1.0{\times}10^{-7}$ to $1.0{\times}10^{-5}$ M, with a correlation coefficient of 0.998 on the anodic current. The lower detection limit was calculated as 5.0 nM. Due to the relatively low currents and difference of potentials in the electrochemical responses of uric acid (UA), ascorbic acid (AA), and dopamine (DA), the modified electrode was a useful and effective sensing device for the selective and sensitive serotonin determination in the presence of UA, AA, and DA.

Pyrrole-Derivative of Chalcone, (E)-3-Phenyl-1-(2-Pyrrolyl)-2-Propenone, Inhibits Inflammatory Responses via Inhibition of Src, Syk, and TAK1 Kinase Activities

  • Yang, Sungjae;Kim, Yong;Jeong, Deok;Kim, Jun Ho;Kim, Sunggyu;Son, Young-Jin;Yoo, Byong Chul;Jeong, Eun Jeong;Kim, Tae Woong;Han Lee, In-Sook;Cho, Jae Youl
    • Biomolecules & Therapeutics
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    • v.24 no.6
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    • pp.595-603
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    • 2016
  • (E)-3-Phenyl-1-(2-pyrrolyl)-2-propenone (PPP) is a pyrrole derivative of chalcone, in which the B-ring of chalcone linked to ${\beta}$-carbon is replaced by pyrrole group. While pyrrole has been studied for possible Src inhibition activity, chalcone, especially the substituents on the B-ring, has shown pharmaceutical, anti-inflammatory, and anti-oxidant properties via inhibition of NF-${\kappa}B$ activity. Our study is aimed to investigate whether this novel synthetic compound retains or enhances the pharmaceutically beneficial activities from the both structures. For this purpose, inflammatory responses of lipopolysaccharide (LPS)-treated RAW264.7 cells were analyzed. Nitric oxide (NO) production, inducible NO synthase (iNOS) and tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) mRNA expression, and the intracellular inflammatory signaling cascade were measured. Interestingly, PPP strongly inhibited NO release in a dose-dependent manner. To further investigate this anti-inflammatory activity, we identified molecular pathways by immunoblot analyses of nuclear fractions and whole cell lysates prepared from LPS-stimulated RAW264.7 cells with or without PPP pretreatment. The nuclear levels of p50, c-Jun, and c-Fos were significantly inhibited when cells were exposed to PPP. Moreover, according to the luciferase reporter gene assay after cotransfection with either TRIF or MyD88 in HEK293 cells, NF-${\kappa}B$-mediated luciferase activity dose-dependently diminished. Additionally, it was confirmed that PPP dampens the upstream signaling cascade of NF-${\kappa}B$ and AP-1 activation. Thus, PPP inhibited Syk, Src, and TAK1 activities induced by LPS or induced by overexpression of these genes. Therefore, our results suggest that PPP displays anti-inflammatory activity via inhibition of Syk, Src, and TAK1 activity, which may be developed as a novel anti-inflammatory drug.