• Title/Summary/Keyword: meso-Porphyrin

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Polymeric Acetate-Selective Electrodes Based on meso-(α,α,α,α)-Tetrakis-[(2-arylphenylurea)phenyl]porphyrins: Electormic and pH Effects

  • Lee, Hyo-Kyoung;Song, Ki-ju;Seo, Hyung-Ran;Jeon, Seung-won
    • Bulletin of the Korean Chemical Society
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    • v.23 no.10
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    • pp.1409-1412
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    • 2002
  • Polymeric membrane electrodes for acetate anion based on meso-(${\alpha}$,${\alpha}$,${\alpha}$,${\alpha}$)-5,10,15,20-tetrakis[2-(penta-fluorophenylurea) phenyl]porphyrin I and similar urea-functionalized porphyrins Ⅱ-Ⅳ as neutral ionophores were prepared. The membrane based on porphyrin I exhibits the best potentiometric properties in pH 6.0 rather than pH 7.0: linear stable response over a wide concentration range (6.0 ${\times}$$10^{-5}$-1.0 ${\times}$$10^{-2}$) with a slope of -59.6 mV/decade and a detection limit of log[CH3CO$O^-$] = -5.32. Selectivity coefficients obtained from the matched potential method (MPM) in pH 6.0 indicate that interferences of hydrophobic anions are very small for the membranes of porphyrins I and II having the strong withdrawing group. The electronic effect of urea-functionalized porphyrins and pH effect of buffer solutions are discussed on the potentiometric response.

Sandwich Intermediate Sitting-atop Complexation between Free Base meso-tetraarylporphyrins and Tellurium(IV) chloride

  • Dehghani, Hossein;Bakhshayesh, Sara;Shaterian, Maryam;Motamedi, Leila
    • Bulletin of the Korean Chemical Society
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    • v.31 no.4
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    • pp.815-818
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    • 2010
  • Free base meso-tetraarylporphyrins ($H_2T(X)PP$) react with tellurium(IV) chloride ($TeCl_4$) in mild conditions for formation sandwich intermediate sitting-atop (i-SAT) complexes, [$TeCl_4(H_2T(X)PP)_2$]. $^1H$ NMR, $^{13}C$ NMR, UV-vis, FT-IR and elemental analysis were used for characterization of the products. In the proposed structure of the i-SAT complexes, four pyrroles of each porphyrin ring are tilted alternatively up and down and this appropriates suitable orientation of lone pairs of two pyrrolenine nitrogens for electron donation to a tellurium center. $^1H$ NMR and FT-IR results showed that in the produced complex, hydrogen atoms of porphyrin macrocycles remained on the pyrrole nitrogens.

Synthesis and Spectroscopic Characterization of the New Sitting-atop Complexes from Reaction of Zirconyl Nitrate and Free Base meso-Tetraarylporphyrins in Mild Conditions

  • Dehghani, Hossein;Mansournia, Mohammad Reza
    • Bulletin of the Korean Chemical Society
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    • v.30 no.8
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    • pp.1715-1718
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    • 2009
  • A series of sitting-atop (SAT) complexes, [(ZrO)$H_2t(X)pp(NO_3)_2$], have been prepared via the reactions of free base meso-tetraarylporphyrins, $H_2$t(X)pp, with zirconyl nitrate hydrate, ZrO(N$O_3)_2{\cdot}xH_2$O. The products have been characterized by a variety of methods including $^1H\;NMR,\;^{13}C$ NMR, IR and UV-Vis spectroscopies, elemental analysis and conductance measurements. The data indicate that the meso-tetraarylporphyrins coordinate with two pyrrolenine nitrogen atoms to the zirconyl cation located above the distorted porphyrin plane and two protons remain on the pyrrole nitrogens. Such half sandwich-type sitting-atop complexes may be considered as models for the initial steps of the metallation of the macrocycles.

Synthesis of Copolyimide Containing 5,15-Bis(mesityl)-10,20-bis(4-amino)porphyrin (5,15-Bis(mesityl)-10,20-bis(4-amino)porphyrin을 포함하는 Copolyimide의 합성)

  • Kim, Hooi-Sung;Lee, Min-Ho;Kim, Chun-Ho;Kim, Mi-Ra;Lee, Jin-Kook
    • Applied Chemistry for Engineering
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    • v.10 no.6
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    • pp.828-831
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    • 1999
  • 5,15-Bis(mesityl)-10,20-bis(4-amino)porphyrin was synthesized with meso-(mesityl)dipyrromethane and 4-nitrobenzaldehyde. It was characterized with $^1H$-NMR spectroscopy, UV spectrophotometer, and GC-MASS. In UV spectrum, Soret-band(438 nm) and Q-bands(526, 572, 611 nm) were confirmed. In NMR spectrum, the characteristic peak of porphyrin was detected at -2.65 ppm. Copolyimide containing porphyrin structure was synthesized with mesityl-$TPP(NH_2)$, 3,3',4,4'-benzophenonetetracarboxylic dianhydride(BTDA) and 2,2-bis(4-(4-aminophenoxy)phenyl) hexafluoropropane(BAPHF) and characterized with UV and FT-IR spectrophotometer. The $T_g$ and $T_m$ of the synthesized copolyimide were 220.7 and $369.2^{\circ}C$, respectively.

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Interaction of Cu(II)-meso-tetrakis(n-N-methylpyridiniumyl)porphyrin (n = 2,3,4) with Native and Synthetic Polynucleotides Probed by Polarized Spectroscopy

  • Lee, Mi-Jin;Lee, Gil-Jun;Lee, Dong-Jin;Kim, Seog-K.;Kim, Jong-Moon
    • Bulletin of the Korean Chemical Society
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    • v.26 no.11
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    • pp.1728-1734
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    • 2005
  • The interactions of Cu(II)-meso-Tetrakis(n-N-methylpyridiniumyl)porphyrin (n = 2,3,4), respectively referred to as o-, m- and p-CuTMPyP, and DNA, poly$[d(A-T)_2]$ and poly$[d(G-C)_2]$ were investigated by circular and linear dichroism (CD and LD). In the o-CuTMPyP case, in which the rotation of the pyridinium ring is prevented, the shape of the CD spectrum when associated to DNA and poly$[d(A-T)_2]$ resembles and is characterized by a positive band at a low drug to DNA concentration ratio (R ratio) and is bisignate at a high R ratio. The former CD spectrum shape has been attributed to porphyrin that is bound monomerically outside of DNA while the latter can be attributed to those that are stacked. When o-CuTMPyP is bound to poly$[d(G-C)_2]$, the excitonic CD appeared at a relatively high R ratio. In contrast, a characteristic negative CD band in the Soret region was apparent for both m- and p-CuTMPyP when bound to DNA and poly$[d(G-C)_2]$ at the low R ratios, indicating that the porphyrin molecule intercalates. However, the DNA is bent near the intercalation site and the plane of the porphyrin molecule tilts relative to the DNA helix axis, as judged by the magnitude of the reduced LD. Various stacking patterns were identified by the shape of the CD spectrum for m- and p-CuTMPyP when bound to poly$[d(A-T)_2]$. Three species for the former complex and two for the latter complex were found which may reflect the extent of the stacking.

Relaxation Process of the Photoexcited State and Singlet Oxygen Generating Activity of Water-soluble meso-Phenanthrylporphyrin in a DNA Microenvironment

  • Hirakawa, Kazutaka;Ito, Yusuke;Yamada, Takashi;Okazaki, Shigetoshi
    • Rapid Communication in Photoscience
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    • v.3 no.4
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    • pp.81-84
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    • 2014
  • To examine the microenvironmental effect of DNA on the photosensitized reaction, the electron-donor-connecting porphyrin, meso-(9-phenanthryl)-tris(N-methyl-p-pyridinio) porphyrin (Phen-TMPyP), was synthesized. Phen-TMPyP can bind to oligonucleotides with two binding modes, depending on the DNA concentration. The fluorescence lifetime measurement of Phen-TMPyP shows a shorter component than that of the reference porphyrin without the phenanthryl moiety. However, the observed value is much longer than those of previously reported similar types of electron-donor-connecting porphyrins, suggesting that electron-transfer quenching by the phenanthryl moiety is not sufficient. The fluorescence quantum yield of Phen-TMPyP ($5{\mu}M$) decreased with an increase in DNA concentration of up to $5{\mu}M$ base pair (bp), possibly due to self-quenching through an aggregation along the DNA strand, increased with an increase in DNA concentration of more than $5{\mu}M$ bp and reached a plateau. The fluorescence quantum yield of Phen-TMPyP with a sufficient concentration of DNA was larger than that of the reference porphyrin. The singlet oxygen ($^1O_2$) generating activity of Phen-TMPyP was confirmed by the near-infrared emission spectrum measurement. The quantum yield of $^1O_2$ generation was decreased by a relatively small concentration of DNA, possibly due to the aggregation of Phen-TMPyP, and recovered with a sufficient concentration of DNA. The recovered quantum yield was rather smaller than that without DNA, indicating the quenching of $^1O_2$ by DNA. These results show that a DNA strand can stabilize the photoexcited state of a photosensitizer and, in a certain case, suppresses the $^1O_2$ generation.

The Cytotoxic Action of New Ag-Porphyrin as a Potential Chemotherapeutic Agent

  • Nelli, Babayan;Artak, Tovmasyan;Ani, Gevorkyan;Gennadi, Gasparyan;Rouben, Aroutiounian
    • Korean Journal of Environmental Biology
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    • v.26 no.2
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    • pp.115-120
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    • 2008
  • Earlier we have described new water-soluble Ag- and Zn-derivatives of tetrachloride meso-tetra (4-N-oxiethylpyridyl) porphyrin (TOEtPyP) as potential anticancer drugs. In this work the effect of one of these metal porphyrins, TOEtPyP Ag, on the cell population kinetics was studied in vitro using morphological and biochemical techniques. The results suggested that TOEtPyP Ag action consisted in the simultaneous suppression of the cell growth and activation of the cell death. About 40% of the cells were shown to die via apoptotic pathway. So, the porphyrin studied may be attributed to inducers of both necrotic and apoptotic processes. The results obtained support our previous assertion that TOEtPyP Ag may be considered as a potential chemotherapeutic agent.

Synthesis and Band Gap Analysis of Meso-Arylporphyrins Containing Exclusively Electron Donating or Withdrawing Groups

  • Min Su Kang;Kwang-Jin Hwang
    • Journal of the Korean Chemical Society
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    • v.67 no.3
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    • pp.175-180
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    • 2023
  • Tetra-aryl substituted A4-type porphyrins (TP, TD, TA) and trans-A2B2 porphyrins (DDP1, AAP1) with electron-donating or withdrawing groups were synthesized. The band gap energy of those porphyrins was calculated from their UV-Vis spectra and CV data. With an electron-withdrawing group, the band gap energy of porphyrin TA increased via the LUMO energy up. Meanwhile, the introduction of an electron-donating group decreased the band gap of porphyrin by HOMO level up as as in the case of porphyrin TD. The band gap (2.19-2.28 eV) of metalloporphyrin PP-Ni was greater than those (1.81-2.06 eV) of non-metalloporphyrins PP due to the LUMO level up.