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Synthesis of Asymmetrical Porphyrins Substituted in the meso-Position from Dipyrrolomethanes  [PDF]
E. Milanesio,S. M. Chiacchiera,J. J. Silber,E. N. Durantini
Molecules , 2000, DOI: 10.3390/50300531
Abstract: A convenient procedure for the synthesis of 5-(4-acetamidophenyl)-10,15,20-tris(4-substituted phenyl) porphyrins from dipyrrolomethane is reported. meso-(4-Substituted phenyl) dipyrrolomethanes were obtained in yields of 72-84%. The amide porphyrins were isolated with appreciable yields of 15-17%.
Structural and Molecular Characterization of meso-Substituted Zinc Porphyrins: A DFT Supported Study  [PDF]
Rudolf S?ota,Ma?gorzata A. Broda,Gabriela Dyrda,Krzysztof Ejsmont,Giuseppe Mele
Molecules , 2011, DOI: 10.3390/molecules16129957
Abstract: Structural parameters of a range of over 100 meso-substituted zinc porphyrins were reviewed and compared to show how far the nature of the functional group may affect the interatomic distances and bond angles within the porphyrin core. It was proved that even despite evident deformations of the molecular structure, involving twisting of the porphyrin's central plane, the coupled π-bonding system remains flexible and stable. DFT calculations were applied to a number of selected porphyrins representative for the reviewed compounds to emphasize the relevance of theoretical methods in structural investigations of complex macrocyclic molecular systems. Experimental and DFT-simulated IR spectral data were reported and analyzed in context of the individual molecular features introduced by the meso substituents into the porphyrin moiety base. Raw experimental spectral data, including 1H- and 13C-NMR, UV-Vis, FTIR, XRD, and other relevant physicochemical details have been provided for a specially chosen reference zinc porphyrin functionalized by tert-butylphenyl groups.
Synthesis and characterization of a novel series of meso (nitrophenyl) and meso (carboxyphenyl) substituted porphyrins
Schiavon, Marco A.;Iwamoto, Lidia S.;Ferreira, Ant?nio G.;Iamamoto, Yassuko;Zanoni, Maria V. B.;Assis, Marilda das D.;
Journal of the Brazilian Chemical Society , 2000, DOI: 10.1590/S0103-50532000000500005
Abstract: the anionic 5,10,15-tris(4-carboxyphenyl), 20-mono(2-nitrophenyl) porphyrin (1), 5,10(or 15)-bis(4-carboxyphenyl), 15(or 10),20-bis(2-nitrophenyl)porphyrin (2) and 5-mono(4-carboxyphenyl), 10,15,20-tris(2-nitrophenyl)porphyrin (3) were sinthesized directly by reaction of pyrrole with substituted benzaldehydes in nitrobenzene/propionic acid media. the benzaldehydes molar ratio was controlled to optimize the synthesis and purification of the desired porphyrins. this new series of porphyrins was characterised by tlc, mass spectrometry (fab ms), 1h nmr, uv/vis, ir and electrochemistry. 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin (4) and 5,10,15,20-tetrakis(2-nitrophenyl)porphyrin (5) were also characterised for comparative purposes, completing the series the electrochemical reduction was investigated for the free base and corresponding iron(iii) porphyrins on glassy carbon and mercury electrodes. the reduction potentials showed the expected dependence on the number of electron-withdrawing nitro groups present on the porphyrin ring providing additional evidences for the characterisation of the synthesised compounds.
Synthesis and characterization of a novel series of meso (nitrophenyl) and meso (carboxyphenyl) substituted porphyrins  [cached]
Schiavon Marco A.,Iwamoto Lidia S.,Ferreira Ant?nio G.,Iamamoto Yassuko
Journal of the Brazilian Chemical Society , 2000,
Abstract: The anionic 5,10,15-tris(4-carboxyphenyl), 20-mono(2-nitrophenyl) porphyrin (1), 5,10(or 15)-bis(4-carboxyphenyl), 15(or 10),20-bis(2-nitrophenyl)porphyrin (2) and 5-mono(4-carboxyphenyl), 10,15,20-tris(2-nitrophenyl)porphyrin (3) were sinthesized directly by reaction of pyrrole with substituted benzaldehydes in nitrobenzene/propionic acid media. The benzaldehydes molar ratio was controlled to optimize the synthesis and purification of the desired porphyrins. This new series of porphyrins was characterised by TLC, mass spectrometry (FAB MS), 1H NMR, UV/Vis, IR and electrochemistry. 5,10,15,20-Tetrakis(4-carboxyphenyl)porphyrin (4) and 5,10,15,20-Tetrakis(2-nitrophenyl)porphyrin (5) were also characterised for comparative purposes, completing the series The electrochemical reduction was investigated for the free base and corresponding iron(III) porphyrins on glassy carbon and mercury electrodes. The reduction potentials showed the expected dependence on the number of electron-withdrawing nitro groups present on the porphyrin ring providing additional evidences for the characterisation of the synthesised compounds.
Charge effect on the photoinactivation of Gram-negative and Gram-positive bacteria by cationic meso-substituted porphyrins
Eliana Alves, Liliana Costa, Carla MB Carvalho, Jo?o PC Tomé, Maria A Faustino, Maria GPMS Neves, Augusto C Tomé, José AS Cavaleiro, ?ngela Cunha, Adelaide Almeida
BMC Microbiology , 2009, DOI: 10.1186/1471-2180-9-70
Abstract: Bacterial suspension (107 CFU mL-1) treated with different photosensitizers concentrations (0.5, 1.0 and 5.0 μM) were exposed to white light (40 W m-2) for a total light dose of 64.8 J cm-2. The most effective photosensitizers against both bacterial strains were the Tri-Py+-Me-PF and Tri-Py+-Me-CO2Me at 5.0 μM with a light fluence of 64.8 J cm-2, leading to > 7.0 log (> 99,999%) of photoinactivation. The tetracationic porphyrin also proved to be a good photosensitizer against both bacterial strains. Both di-cationic and the monocationic porphyrins were the least effective ones.The number of positive charges, the charge distribution in the porphyrins' structure and the meso-substituent groups seem to have different effects on the photoinactivation of both bacteria. As the Tri-Py+-Me-PF porphyrin provides the highest log reduction using lower light doses, this photosensitizer can efficiently photoinactivate a large spectrum of environmental bacteria. The complete inactivation of both bacterial strains with low light fluence (40 W m-2) means that the photodynamic approach can be applied to wastewater treatment under natural light conditions which makes this technology cheap and feasible in terms of the light source.Environmental contamination from domestic and industrial waste discharges has become a major public health concern. Wastewater treatment processing includes a final disinfection stage which eliminates pathogenic microorganisms (bacteria, virus and protozoa). Water disinfection can be achieved using chlorine, chlorine dioxide, hypochlorite, ozone or ultraviolet radiation. Although very efficient against a large range of microorganisms, the implementation of these solutions for wastewater treatment has been limited by environmental factors, namely the formation of toxic by-products from chorine [1], or by economic factors, as ultraviolet radiation and ozone treatment that are very expensive options to apply. Thus, as water reuse may be a way to cope with low w
Distortions and Deformations of Metaled Meso-Substituted and Unsubstituted Porphyrins and Derivatives in Crystal Structures  [PDF]
Philippe V. Tsalu, Tharcisse O. Monama, Hilaire V. Mambo, Dorothée D. Tshilanda, Pius T. Mpiana, Bodrique M. Nsimba, Virima Mudogo, Pitchou N. Bokolombe, Damien S. T. Tshibangu, Zephyrin G. Yav
Crystal Structure Theory and Applications (CSTA) , 2016, DOI: 10.4236/csta.2016.51001
Abstract:

Experimental crystallographic structural parameters of a range of metaled meso-substituted and unsubstituted porphyrins were reviewed to show how far the meso-substitution by any functional group and the insertion of metal in the porphyrins core macrocycle may affect the geometry. The analysis of twists and angles has shown two kinds of distortions: external [T(Cβ-Cα-Cmeso-Xn) and T(Cβ-Cα-Cmeso-Cα)] and internal [T(Nm-Cα-Cmeso-Xn) and T(Nn-Cα-Cmeso-Cα)] with averages of [+6° and 6°] and [5° and +5°], respectively.

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In the meso-substituted case, the external and internal twists Cβ-Cα-Cmeso-X and N-Cα-Cmeso-X, respectively are oppositely orientated. Similar effect is observed in meso-unsubstituted of Cβ-Cα- Cmeso-H and N-Cα-Cmeso-H. However, the external distortions are more significant than internal. Considering the same order, the limit of distortions is [97° and 132° (48°)] for external and [91° (89

Novel, Meso-Substituted Cationic Porphyrin Molecule for Photo-Mediated Larval Control of the Dengue Vector Aedes aegypti  [PDF]
Leonardo Lucantoni ,Michela Magaraggia,Giulio Lupidi,Robert Kossivi Ouedraogo,Olimpia Coppellotti,Fulvio Esposito,Clara Fabris,Giulio Jori,Annette Habluetzel
PLOS Neglected Tropical Diseases , 2011, DOI: 10.1371/journal.pntd.0001434
Abstract: Background Control of the mosquito vector population is the most effective strategy currently available for the prevention of dengue fever and the containment of outbreaks. Photo-activated oxidants may represent promising tools for developing effective, safe and ecofriendly novel larvicides. The purpose of this study was to evaluate the potential of the synthetic meso-substituted porphyrin meso-tri(N-methylpyridyl), meso-mono(N-tetradecylpyridyl)porphine (C14) as a photoactivatable larvicide against the dengue vector Aedes (Stegomyia) aegypti. Methodology The photophysical and photochemical properties of the C14 molecule were assessed spectrophotometrically. Photomediated larvicidal efficacy, route of intake and site of action were determined on Ae. aegypti larvae by laboratory bioassays and fluorescence microscopy. Using powdered food pellet for laboratory rodents (a common larval food used in the laboratory) as a carrier for C14, loading-release dynamics, larvicidal efficacy and residual activity of the C14-carrier complex were investigated. Main Findings The C14 molecule was found to exert a potent photosensitizing activity on Ae. aegypti larvae. At irradiation intervals of 12 h and 1 h, at a light intensity of 4.0 mW/cm2, which is 50–100 times lower than that of natural sunlight, LC50 values of 0.1 μM (0.15 mg/l) and 0.5 μM (0.77 mg/l) were obtained, respectively. The molecule was active after ingestion by the larvae and caused irreversible, lethal damage to the midgut and caecal epithelia. The amphiphilic nature of C14 allowed a formulate to be produced that not only was as active against the larvae as C14 in solution, but also possessed a residual activity of at least two weeks, in laboratory conditions. Conclusions The meso-substituted synthetic porphyrin C14, thanks to its photo-sensitizing properties represents an attractive candidate for the development of novel photolarvicides for dengue vector control.
Fluorescence and FTIR Spectra Analysis of Trans-A2B2-Substituted Di- and Tetra-Phenyl Porphyrins  [PDF]
P?nar ?en,Catherine Hirel,Chantal Andraud,Christophe Aronica,Yann Bretonnière,Abdelsalam Mohammed,Hans ?gren,Boris Minaev,Valentina Minaeva,Gleb Baryshnikov,Hung-Hsun Lee,Julien Duboisset,Mikael Lindgren
Materials , 2010, DOI: 10.3390/ma3084446
Abstract: A series of asymmetrically substituted free-base di- and tetra-phenylporphyrins and the associated Zn-phenylporphyrins were synthesized and studied by X-ray diffraction, NMR, infrared, electronic absorption spectra, as well as fluorescence emission spectroscopy, along with theoretical simulations of the electronic and vibration structures. The synthesis selectively afforded trans-A 2B 2 porphyrins, without scrambling observed, where the AA and BB were taken as donor- and acceptor-substituted phenyl groups. The combined results point to similar properties to symmetrically substituted porphyrins reported in the literature. The differences in FTIR and fluorescence were analyzed by means of detailed density functional theory (DFT) calculations. The X-ray diffraction analysis for single crystals of zinc-containing porphyrins revealed small deviations from planarity for the porphyrin core in perfect agreement with the DFT optimized structures. All calculated vibrational modes (2162 modes for all six compounds studied) were found and fully characterized and assigned to the observed FTIR spectra. The most intense IR bands are discussed in connection with the generic similarity and differences of calculated normal modes. Absorption spectra of all compounds in the UV and visible regions show the typical ethio type feature of meso-tetraarylporphyrins with a very intense Soret band and weak Q bands of decreasing intensity. In diphenyl derivatives, the presence of only two phenyl rings causes a pronounced hypsochromic shift of all bands in the absorption spectra. Time-dependent DFT calculations revealed some peculiarities in the electronic excited states structure and connected them with vibronic bands in the absorption and fluorescence spectra from associated vibrational sublevels.
Preparation and evaluation of [67Ga]-Tetra Phenyl Porphyrin complexes as imaging agents
Seyed Yousef Fazaeli Hoseini Nezhad,Amir Reza Jalilian,Mostafa Mohammadpour Amini,Ali Rahiminejad-kisomi
Iranian Journal of Nuclear Medicine , 2010,
Abstract: Introduction: Radiolabeled porphyrins have been developed for the therapeutic purposes such as, 109Pd-protoporphyrins [1], 109Pd-porphyrins [2], and 188Re-porphyrin [3].In this work we report, synthesis, radiolabeling, partition coefficient, quality control and biodistribution studies (using: SPECT and scarification) of 67Ga-TPP in wild-type rats. key words: [67Ga]-Tetra phenyl porphyrin, imaging agents Methods: [67Ga]labeled tetraphenyl porphyrin ([67Ga]-TPP) was prepared using freshly prepared [67Ga]GaCl3 and tetraphenyl porphyrin (TPPH2) for 30-60 min at 25°C (radiochemical purity: >97% ITLC, >98% HPLC, specific activity: 13-14 GBq/mmol). Stability of the complex was checked in final formulation and human serum for 24 h. The partition coefficient was calculated for the compound (log P. 1.89). The biodistribution of the labeled compound in vital organs of wild-type rats was studied using scarification studies and SPECT imaging up to 24 h. A detailed comparative pharmacokinetic study performed for 67Ga cation and [67Ga]-TPP. Results: Total labeling and formulation of [67Ga]-TPP took about 30-60 min (RCP >97% ITLC, >98% HPLC, specific activity: 13-14 GBq/mmol). The complex was stable in final formulation and human serum at least for 24 h. At the pH.7, the logP was 1.89. The biodistribution of the labeled compound in vital organs of wild-type rats was studied using scarification studies and SPECT imaging up to 24 h. The complex is mostly washed out from the circulation through kidneys and can be an interesting tumor imaging/targeting agent due to low liver uptake and rapid excretion through the urinary tract. Conclusion: It is suggested that 67Ga-TPP could be a possible SPECT tracer, however considering the fast wash-out, the short half life gallium-68 can be a suitable candidate for tumor imaging applications and future 68Ga-PET studies and less imposed radiation doses to patients.
A Singlet Oxygen Photogeneration and Luminescence Study of Unsymmetrically Substituted Mesoporphyrinic Compounds  [PDF]
Anabela Sousa Oliveira,Dumitru Licsandru,Rica Boscencu,Radu Socoteanu,Veronica Nacea,Luis Filipe Vieira Ferreira
International Journal of Photoenergy , 2009, DOI: 10.1155/2009/413915
Abstract: This paper deals with a series of new unsymmetrically substituted mesoporphyrins: 5-(2-hydroxyphenyl)-10,15,20-tris-phenyl-21,23-H-porphyrin (TPPOHO), 5-(3-hydroxyphenyl)-10,15,20-tris-phenyl-21,23-H-porphyrin (TPPOHM), 5-(4-hydroxyphenyl)-10,15,20-tris-phenyl-21,23-H-porphyrin (TPPOHP), 5-(2-hydroxyphenyl)-10,15,20-tris-butyl-21,23-H-porphyrin (TBPOHO), and their parent nonsubstituted compounds, respectively, 5,10,15,20-tetrakis-phenyl-21,23-H-porphyrin (TPP) and 5,10,15,20-tetrakis-butyl-21,23-H-porphyrin (TBP). Several photophysical studies were carried out to access the influence of the unsymmetrical substitution at the porphyrinic macrocycle on porthyrin's photophysical properties, especially porthyrin's efficiency as singlet oxygen sensitizers. The quantum yields of singlet oxygen generation were determined in benzene (ΦΔ(TPP) = 0.66 ± 0.05; ΦΔ(TPPOHO) = 0.69 ± 0.04; ΦΔ(TPPOHM) = 0.62 ± 0.04; ΦΔ(TPPOHP) = 0.73 ± 0.03; ΦΔ(TBP) = 0.76 ± 0.03; ΦΔ(TBPOHO) = 0.73 ± 0.02) using the 5,10,15,20-tetraphenyl-21,23-H-porphine (ΦΔ(TPP) = 0.66) and Phenazine (ΦΔ(Phz) = 0.83) as reference compounds. Their fluorescence quantum yields were found to be (Φf(TPPOHO) = 0.10 ± 0.04; Φf(TPPOHM) = 0.09 ± 0.03; Φf(TPPOHP) = 0.13 ± 0.02; Φf(TBP) = 0.08 ± 0.03 and Φf(TBPOHO) = 0.08 ± 0.02 using 5,10,15,20-tetraphenyl-21,23-H-porphine as reference Φf(TPP) = 0.13). Singlet state lifetimes were also determined in the same solvent. All the porphyrins presented very similar fluorescence lifetimes (mean values of S (with O2, air equilibrated) = 9.6 ± 0.3 nanoseconds and (without O2, argon purged) = 10.1 ± 0.6 nanoseconds, resp.). The phosphorescence emission was found to be negligible for this series of unsymmetrically substituted mesoporphyrins, but an E-type, thermally activated, delayed fluorescence process was proved to occur at room temperature.
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