• 제목/요약/키워드: Porphyrins

검색결과 81건 처리시간 0.022초

meso-Substituted Dipyrromethanes from Vinylogous Aromatic Heterocycles and Their Utilization to the Synthesis of meso-Functionalized Porphyrins

  • Hong, Seong-Jin;Lee, Mi-Hye;Lee, Chang-Hee
    • Bulletin of the Korean Chemical Society
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    • 제25권10호
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    • pp.1545-1550
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    • 2004
  • meso-Functionalized dipyrromethanes 6-10 were synthesized by acid-catalyzed addition of pyrrole to ${\alpha}$-position of 2-alkenyl pyrroles. The regiochemistry of the reaction can be explained by either the formation of more stable carbocation intermediate or ${\beta}$-addition of ${\alpha},{\beta}$-unsaturated carbonyl compounds. The starting 2-alkenyl pyrroles were synthesized by Aldol condensation of 2-formylpyrrole with active methylene compounds such as nitromethane, diethylmalonate and malononitrile. Attempted ‘2+2' condensation of meso-diethylmalonyldipyrromethane, meso-(p-tolyl)dipyrromethane and p-tolualdehyde afforded three different porphyrins 12, 13 and 14 in reasonable yields. On the other hand, meso-(nitromethyl)dipyrromethane with p-(tbutyl) benzaldehyde resulted in the formation of three different porphyrins such as 5,15-dicyano-10,20-diarylporphyrin (16), 5-cyano-15-formyl-10,20-diarylporphyrin (17) and 5,15-diformyl-10,20-diarylporphyrin (18) in low yields. Conversion of nitromethyl groups to nitrile and (or) formyl group was observed under the porphyrin forming conditions.

An Isothermal Titration Microcalorimetric Study on the Interaction of Three Water-Soluble Porphyrins with Histone H2B

  • Bordbar, A.K.;Ghaderi, A.R.;Safaei, E.;Tangestaninejad, S.;Eslami, A.;Saboury, A.A.;Moosavi Movahedi, A.A.
    • Bulletin of the Korean Chemical Society
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    • 제24권5호
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    • pp.547-551
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    • 2003
  • In the present work, the interaction of three water soluble porphyrins, tetra(p-trimethyle) ammonium phenyl porphyrin iodide (TAPP) as a cationic porphyrin, tetra sodium meso-tetrakis (p-sulphonato phenyle) porphyrin (TSPP) as an anionic porphyrin and manganese tetrakis (p-sulphonato phenyl) porphinato acetate (MnTSPP) as a metal porphyrin, with histone H₂B have been studied by isothermal titration microcalorimetry at 8 mM phosphate buffer, pH 6.8 and 27 °C. The values of binding constant, entropy, enthalpy and Gibbs free energy changes for binding of the first MnTSPP, and first and second TSPP and TAPP molecules were estimated from microcalorimetric data analysis. The results represent that the process is both entropy and enthalpy driven and histone induces self-aggregation of the porphyrins. The results indicate that both columbic and hydrophobic interactions act as self-aggregation driving forces for the formation of aggregates around histone.

Mn(III)-porphyrin에 의한 Styrene 유도체의 산화반응 메카니즘 연구 (Kinetic Investigation of Styrene Derivatives Oxidation Mechanism by Mn(III)-porphyrin)

  • 나훈길
    • 한국응용과학기술학회지
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    • 제19권3호
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    • pp.206-212
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    • 2002
  • The catalytic activities of several metalloporphyrin, wherein the porphyrins are TPP(5,lO,l5,20-Tetraphenyl-21H,23H-porphyrin) and (p-X)TPP (X =$CH_{3}O$, $CH_{3}$, F, Cl), are reported for the oxidation of styrene and it's derivatives. The electronic effects of substrates and porphyrins on the catalytic activity of metalloporphyrin containing the transition metal ion such as Mn(III) was discussed. Investigating the correlation between the Michaelis-Menten's rate parameters and the substituent constants, we are going to analyze the influences on the changes of catalytic activity or rate determining step during the processes of the formation and the dissociation of the M-oxo-olefin.

Effect of Cationic and Anionic Porphyrins on the Structure and Activity of Adenosine Deaminase

  • Ajloo, Davood;Hajipour, Samaneh;Saboury, Ali Akbar;Zakavi, Saeed
    • Bulletin of the Korean Chemical Society
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    • 제32권9호
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    • pp.3411-3420
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    • 2011
  • Kinetic and structural studies have been carried out on the effects of meso-tetrakis(4-sulfonatophenyl)-porphyrin ($H_2TPPS_4$) as an anionic and meso-tetrakis(3-N-methyl-pyridyl)porphyrin ($H_2TMPYP$) as a cationic porphyrin with adenosine deaminase (ADA) in 25 mM citrate/phosphate buffer, pH = 4-8, at $37^{\circ}C$ using UVvis spectrophotometry, circular dichroism (CD), fluorescence spectrophotometry as well as molecular dynamics (MD) and molecular docking. Kinetic results showed that the two porphyrins are non-competitive inhibitors. Increasing pH, increases $K_I$ and cationic porphyrin has a higher $K_I$ and lower binding constant ($K_b$) at all pH ranges. Analyzing the secondary structure revealed that both ligands decrease the secondary structure and that the anionic porphyrin is more effective.

NMR Study on Binding Interactions of Cationic Porphyrin Derivatives with double helical $d(CGCGAATTCGCG)_2$

  • Huh, Sungho;Hong, Seokjoo
    • 한국자기공명학회논문지
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    • 제5권2호
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    • pp.118-129
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    • 2001
  • Binding interactions of cationic porphyrins, T4MPyP and TMAP with DNA oligomer d(CGCGAATTCGCG), were studied with NMR spectroscopy, W and CD spectroscopic method. Two porphyrins showed significant differences in NMR, UV and CD data upon binding to DNA. T4MPyP was considered to position more closely to DNA bases through partial intercalation as well as ionic intercalation between the positive charges of porphyrin and phosphate group of DNA at 5’-GC-3’steps. Contrast to this, TMAP was thought to bind to phosphate of DNA more or less outside of the groove.

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Synthesis and Properties of Soluble and Stable Silyl End-capped Bis-thienylanthracene Oligomers

  • Choi, Jung-Hei;Cho, Dae-Won;Sung, Nam-Kyoung;Jin, Sung-Ho;Yoon, Ung-Chan
    • Bulletin of the Korean Chemical Society
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    • 제28권11호
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    • pp.1931-1938
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    • 2007
  • Analyzed are recent advances in design of novel boronared conjugates of synthetic and natural porphyrins and chlorins. These compounds showed high efficacy as cytotoxic agents for tumor cells in culture and as phototoxins in photodynamic therapy of tumor xenografts. Thus, boronated porphyrins and chlorins emerge as promising class of anticancer agents with potentially multiple advantages: the chemotherapeutic drugs alone and photo- and radiosensitizers in binary treatments.

The pH Dependence of Metal Tetrakis (4-sulfonato-phenyl) porphine Structure Probed by Raman Spectroscopy

  • 윤민중;;김동호
    • Bulletin of the Korean Chemical Society
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    • 제9권1호
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    • pp.40-44
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    • 1988
  • The pH dependence studies of Raman spectra are reported for water-soluble free-base, Zn, Co and Cu tetrakis (4-sulfonatophenyl) porphine in pH 4, pH 7 and pH 13.9 aqueous solution. For free base porphine, the substantial differences are found in absorption and Raman spectra between pH 4 and pH 7 or pH 10 aqueous solutions due to the protonation at low pH. For Zn and Co porphyrins, the hydrolysis equilibrium constants are obtained by spectrophotometric titration experiments. The consistent shifts in Raman frequencies are found at high pH due to the hydrolysis. For Cu porphyrins, instead of hydrolysis the aggregation effect is detected at high pH through the absorption and Raman studies.