• 제목/요약/키워드: Porphyrins

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Ga(III)-, In(III)-, TI(III)-porphyrin 유도체를 촉매제로 한 고리성 올레핀의 산화반응 (Cycloolefins Oxidation Reaction Catalyzed by Ga(III)-, In(III)- and TI(III)-Porphyrin Derivatives)

  • 나훈길
    • 한국응용과학기술학회지
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    • 제21권1호
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    • pp.76-88
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    • 2004
  • The catalytic oxidation reaction of several cycloolefins in $CH_2Cl_2$ have been investigated using non-redox metalloporphyrin(M = Ga(III), In(III) and TI(III) complexes as a catalyst and sodium hypochlorite as a terminal oxidant. Porphyrins were $(p-CH_3O)$TPP, $(p-CH_3)$TPP, TPP, (p-F)TPP, (p-Cl)TPP and $(F_{20})$TPP (TPP=5,10,15,20-tetraphenyl-21H,23H-porphyrin) and olefins were cyclopentene, cyclohexene, cycloheptene and cyclooctene, The substrate conversion yield(%) was investigated according to the radius effect of non-redox metal ion, substituent effect and hindrance effect of metalloporphyrin. The conversion yield of cycloolefin was in the following order : $C_5$ < $C_6$ < $C_7$ = $C_8$.

Zn(II)porphyrin Helical Arrays: A Strategy to Overcome Conformational Heterogeneity by Host-Guest Chemistry

  • Yoon, Zin-Seok;Easwaramoorthi, Shanmugam;Kim, Dong-Ho
    • Bulletin of the Korean Chemical Society
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    • 제29권1호
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    • pp.197-201
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    • 2008
  • Conformational heterogeneity of directly linked multiporphyrin arrays with larger molecular length retards their utilities in practical applications such as two-photon absorption and molecular photonic wire. In this regard, here we adopted a way to overcome the conformational heterogeneity through hydrogen bonding by selective binding of meso aryl substituents of porphyrins (host) with urea (guest) to form helical structure. Using steady-state and time-resolved spectroscopy, we observed the enhanced fluorescence quantum yield by ~1.8 to 2.4 times, enhanced anisotropy values and the disappearance of fast fluorescence decay component in the host-guest helical forms. In addition, the enhanced nonlinear optical responses of helical arrays infer the extended inter-porphyrin electronic coupling due to a significant change in dihedral angle between the neighboring porphyrin moieties. The current host-guest strategy will provide a guideline to improve the structural homogeneity of the photonic wire.

Olefin Polymerization Activity and Crystal Structure of Alkyliron(Ⅲ) Porphyrin Complexes

  • Oh, Yung-Hee;Swenson, Dale;Goff, Harold M.
    • Bulletin of the Korean Chemical Society
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    • 제24권2호
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    • pp.167-172
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    • 2003
  • Alkyliron(Ⅲ) porphyrins, n-butyliron(Ⅲ) tetraphenylporphyrin, (TPP)Fe-Bu and n-butyliron(Ⅲ) tetrakis-(pentafluorophenyl)porphyrin, $(F_{20}TPP)Fe-Bu$ have been evaluated as suitable for olefin free-radical polymerization. Butyl radicals dissociated from n-butyliron(Ⅲ) porphyrin initiated the polymerization reaction, but the ratio of the propagation was low. The GCMS analysis of the reaction mixture of nbutyliron(Ⅲ) porphyrin and styrene has revealed several products containing two butyl groups, while traces of b-hydrogen-abstracted products were observed. The crystal structure of (TPP)Fe-Bu has been determined. The structure of the n-butyliron(Ⅲ) porphyrin reveals the compound containing five-coordinated iron with the average Fe-N distance of 1.973(1) Å and Fe-C of 2.030(2) Å. The iron atom is displaced by 0.137Å from a four nitrogen mean plane. Crystal system is triclinic, and space group is P-1.

저속 유동용 Pressure Sensitive Paint 기술개발과 응용 (Development of Pressure Sensitive Paint (PSP) Technique for Low-speed Flows and Its Application)

  • 강종훈;이상준
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 추계학술대회
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    • pp.688-693
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    • 2003
  • The PSP technique has been used to measure pressure distribution on a model surface quantitatively. The objective of this study is to develop PSP technique which can be applied to low-speed flows. Four different PSP formulations including two porphyrins (PtOEP and PtTFPP) and two polymers (Poly(TMSP) and RTV-118) were tested and the performance of each combination was checked. In the static calibration, the luminescent intensity of the PSP coatings was measured from 0kPa to 11kPa with 0.5, 1, 2kPa increments. Among 4 PSP formulations tested, the combination of PtOEP and RTV-118 shows the best performance. The PSP technique was applied to an oblique impinging jet to measure the pressure field distribution on the impinging plate.

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

  • Nelli, Babayan;Artak, Tovmasyan;Ani, Gevorkyan;Gennadi, Gasparyan;Rouben, Aroutiounian
    • 환경생물
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    • 제26권2호
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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.

Fluorine-19 NMR Spectroscopic Studies of Phenyl-fluorinated Iron Tetraarylporphyrin Complexes

  • Song, Byung-Ho;Yu, Byung-soo
    • Bulletin of the Korean Chemical Society
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    • 제24권7호
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    • pp.981-985
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    • 2003
  • Fluorine-19 NMR solution measurements have been made for various phenyl-fluorinated iron porphyrin complexes. Large chemical shifts for phenyl fluorine signals of iron(III) and iron(II) are observed, and these signals are sensitive to electronic structure. The chemical shift differences in ortho-phenyl fluorine signals between high-spin ferric and low-spin ferric tetrakis(pentafluorophenyl)porphyrins are approximately 40 ppm, whereas the differences are approximately 7 ppm between high- and low-spin states of ferrous tetrakis(pentafluorophenyl)porphyrin complexes. Analysis of fluorine-19 isotropic shifts for the iron(III) tetrakis(pentafluorophenyl) porphyrin using fluorine-19 NMR indicates there is a sizable contact contribution at the ortho-phenyl fluorine ring position. Large phenyl fluorine-19 NMR chemical shift values, which are sensitive to the oxidation and spin states, can be utilized for identification of the solution electronic structures of iron(III) and iron(II) porphyrin complexes.

Shape Selective Oxygen Transfer to Olefins Catalyzed by Sterically Hindered Iron Porphyrins

  • Ahn, Kwang-Hyun;Groves, John T.
    • Bulletin of the Korean Chemical Society
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    • 제15권11호
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    • pp.957-961
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    • 1994
  • Epoxidation of olefins catalyzed by iron-tetraarylporphyrins were studied to see the shape selectivity in the competing reaction between cis-and trans- or internal and external olefins. Cis-olefins were more reactive than trans-olefins in the competing reaction between cis-and trans-olefins. Interestingly, in the epoxidation of $cis-{\beta}-methystyrene$ by ${\alpha}{\beta}{\alpha}{\beta}$ atropisomer of Fe(III)TNPPPCl and iodosylbenzene, 27% of total product was phenylacetone. The unusually large amount of phenylacetone may be produced by hydride rearrangement of carbocationic intermediate. Regioselectivity of the reaction was also studied by using the most sterically hindered Fe(III)TTPPPCl. In the epoxidation of limonene with Fe(III)TTPPPCl, the disubstituted double bond was more reactive than trisubstituted double bond. This is in contrast to the results obtained with other iron-tetraarylporphyrins. Similar trend was also observed in the competing reaction between mono-and di-substituted olefins.

Synthesis of Core-Modified Porphyins and Studies of Their Temperature-dependent Tautomerism

  • 이창희;김한재;윤대위
    • Bulletin of the Korean Chemical Society
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    • 제20권3호
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    • pp.276-280
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    • 1999
  • The different core-modified porphyrins 21-thia-23-carba-12-aza-5,10-dimesityl-15,20-diphenylporphyrin (6), and their N(12)-methyl derivatives (8) were synthesized by acid-catalyzed [3+1] condensation of the corresponding 16-thia-5,10-dimesityltripyrromethanes and 2,4-bis[(α-hydroxy-α-phenyl)methyl]pyrrole. Spectroscopic evidence indicates the existence of two different tautomeric forms at room temperature in porphyrin (6). A third form of tautomer was observed when the temperature was lowered to 223 K. The most stable tautomer is one in which the nitrogenic proton resides outside the core of the macrocycle. The ratio of the three different tautomers (outer N-H/ two inner N-H, i.e. 6/12/13) was 1/l/0.5 in the case of (6) while the ratio of 1/l/0.3 was observed in the case of (10). In the case of 21-oxa-23-carba-12-aza-5,10,15,20-tetraphenylporphyrin (7), the only stable tautomeric form observed by 1H NMR was the one that nitrogenic proton resides inside the core on

Ga(Ⅲ), In(Ⅲ) 및 Tl(Ⅲ) 금속이온을 포함한 Metalloporphyrin 착물의 촉매적 특성 (Catalytic Activity of Ga(Ⅲ)-, In(Ⅲ)- and Tl(Ⅲ)-porphyrin Complexes)

  • 박유철;나훈길;김성수
    • 대한화학회지
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    • 제39권5호
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    • pp.364-370
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    • 1995
  • 비산화-환원 금속인 Ga(III), In(III), TI(III)을 포함하는 금속 포르피린을 촉매제로 NaOCl을 산화제로 하여 올레핀의 촉매적 산화반응을 $CH_2Cl_2$에서 연구하였다. 포르피린은 $(p-CH_3O)TPP,\;(p-CH_3)TPP,\;TPP,\;(p-F)TPP,\;(p-Cl)TPP $그리고 $(F_20)TPP$를 사용하였다. 올레핀은 $(p-CH_3O)-,\;(p-CH_3)-,\;(p-H)-,\;(p-F)-,\;(p-Cl)-,\;(p-Br)styrene$ 그리고 cyclopentene, cyclohexene을 사용하였다. 올레핀 산화반응에서 기질의 전환율(%)은 금속 포르피린 및 기질의 치환기 효과와 중심 금속이온 성질에 따라 고찰하였다. TPP 치환기에 따른 전환율의 변화는 $p-CH_3O$ < $p-CH_3$ < H < p-F < p-Cl 순서로 증가하였다. 이러한 증가는 TPP의 $4{\sigma}$값의 증가 순서와 일치하였다. 기질의 치환기에 따른 전환율의 변화는 $p-CH_3O$ > $p-CH_3$ > H > p-Cl > p-Br 순서로 치환기의 ${\sigma}^+$값이 증가할수록 오히려 감소하였다. 올레핀의 산화 반응에서 In(III)-, Tl(III)-포르피린은 Ga(III)-포르피린에 비하여 높은 촉매 활성을 나타내었다.

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The Synthetic Approaches to Modify Methyl (Pyro)pheophorbide a

  • Wang, Jin-Jun;Han, Guang-Fan;Lee, Jong-Cheol;Shim, Young-Key
    • Journal of Photoscience
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    • 제9권2호
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    • pp.178-181
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    • 2002
  • Pyropheophorbide and pheophorbide-photosensitizers as chlorin analogues are promising new compounds for PDT because the chlorin analogues are activated with much longer red light at > 670nm and produce less long-term normal tissue phototoxicity than Photofrin. The various chlorin derivatives can be obtained by moditying peripheral substituted group among which meso-H, vinyl group and exocyclic ring are the most active positions. These characteristics prompted us to introduce various groups for constructing modified pyropheophorbide and pheophorbide a compounds. A stereospecific introduction of various double bonds at 3-position was performed to methylpheophorbide a to give a long hydrophobic moiety and cyclic derivatives. Chlorin-C$_{60}$ dyad and chlorin- $C_{60}$-porphyrin triad also were easily prepared by the reaction of terminal aldehyde of methyl pyropheophorbide a. For the reaction on meso $\delta$-position bromination and Vismeier formylation can occur. N,N-dimethylaminoacrolein also reacted on $\delta$-position and was cyclized to isobacteriochlorin, but other modification has not been succeeded. Exocyclic keto function was also modified to give purpurin derivatives, bicyclic and spiro compounds. In this presentation we report a series of modified pyropheophorbide and pheophorbide a derivatives.s.

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