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Cho, Jeongguk. "Porphyrin-catalyzed reduction of nitroaromatic compounds /." Access abstract and link to full text, 1992. http://0-wwwlib.umi.com.library.utulsa.edu/dissertations/fullcit/9307476.
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劉純晶 and Chunjing Liu. "Nonplanar and sterically encumbered ruthenium porphyrins and catalyticreactivity of ruthenium and manganese porphyrin complexes supported onMCM-41." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31237423.
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Rajapakse, Nimal. "Oxidations using dioxoruthenium (VI)-porphyrin complexes ; and studies on some organoruthenium-porphyrin species." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/30767.
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The oxidation of three alkyl thioethers, phenol and 2-propanol by trans-dioxo ruthenium porphyrin species, and the synthesis, characterization and reactivity of several new ruthenium porphyrin complexes are described in this thesis.
The trans-dioxo species Ru(Porp)(O)₂ [Porp= the dianions of 5,10,15,20-tetramesitylporphyrin (TMP) and 5,10,15,20-(2,6-dichlorophenyl)porphyrin (OCP)] selectively oxidize diethyl-, di-n-butyl- and decylmethyl- sulfides to the corresponding sulfoxides at room temperature. The reaction is first order in [Ru] and in [thioether]. The second order rate constants for the first O-atom transfer from the Ru(TMP) system are: 7.54xl0⁻³, 1.23xl0⁻² and 1.14x10-¹ M⁻¹ s⁻¹ respectively for the three thioethers at 20.0 °C. The activation parameters for the O-atom transfer process are also determined: for Et₂S, ∆H‡= 58.3 kJ mol⁻¹ and ∆S‡= -86 J K⁻¹ mol⁻¹; for nBu₂S, AH‡= 47.4 kJ mol⁻¹and ∆S‡= -120 J K⁻¹ mol⁻¹; for DecMeS, ∆H‡= 56.5 kJ mo⁻¹ and ∆S‡= -70 J K⁻¹ mol⁻¹. A second order rate constant of 7.23xl0⁻²M⁻¹s⁻¹ is measured at 20.0 °C for the oxidation of Et₂S by Ru(OCP)(O)₂. The intermediates Ru(TMP)(OSEt₂)₂, Ru(TMP)(OSEt₂)(OSEt₂) and the final product Ru(TMP)(0SEt₂)₂,where O and S refer to O- and S- bonded sulfoxide, are observed by ¹H nmr, and the last mentioned is isolated and characterized. A mechanism is proposed, based on electrophilic attack of the O=Ru=O moiety on :SR₂ to form bis-O-bonded species which subsequently isomerizes to bis-S-bonded species via mixed species. The Ru(TMP)(O)₂/Et₂S/O₂ system at room temperature is catalytic in complex, but produces only about 5 turnovers due to poisoning of the catalyst by the reaction product. The same system at >65 °C gives higher turnovers, but now porphyrin ligand degradation is observed, perhaps via oxidation by the O=Ru=O moiety. The Ru(OCP)(0)₂/Et₂S/O₂ system at 100 °C catalytically oxidizes Et₂S to Et₂SO and Et₂SO₂ (in ~ 4:1 ratio) and the porphyrin ligand does not undergo oxidative destruction. The Ru(TMP)(O)₂ species reacts with phenol via an observed intermediate Ru(TMP)(p-O(H)C₆H₄OH)₂ to form Ru(IV)(TMP)(OC₆H₄OH)₂, a paramagnetic (S=l) complex which is isolated and characterized. The oxidation reaction is first order in both [Ru] and [phenol] with a second order rate constant 6.90x10⁻² M⁻¹ s⁻¹at 20.0 °C. A mechanism based on electrophilic attack by the O=Ru=O moiety on the aryl ring followed by proton migration is proposed. This mechanism also explains the formation of some free para-benzoquinone and 1 equivalent of water per Ru. No ortho-benzoquinone is formed in the reaction.
Preliminary ⁻H nmr studies reveal that 2-propanol is oxidized to acetone by Ru(TMP)(O)₂. A paramagnetic species (S= 1) was isolated as the only porphyrin product but not characterized.
A range of novel ruthenium porphyrin complexes is also prepared. The reaction of acetylene with the four-coordinate Ru(TMP) species forms [Ru(TMP)]₂(u-C₂H₂), the first reported organometallic ruthenium porphyrin dimer. The complexes, Ru(TMP)(PhCCPh) and Ru(TMP)(PhCCH), the first π-bonded alkyne species in ruthenium porphyrin chemistry, are characterized in solution. The π-bonded alkene complexes Ru(TMP)(CH₂CH₂) OPrOH).(iPrOH) and Ru(TMP)(CH₂CH₂) are isolated and characterized, while the Ru(TMP)(cyclohexene) complex is characterized in situ. The Ru(TMP)(OSEt₂)₂ complex is isolated also by the reaction of Ru(TMP)(CH₃CN)₂with Et₂SO. The Ru(TMP)(L)₂ complexes, L= OSMe₂, OSnPr₂ and OSnBu₂ are also prepared via the above method and characterized. Some new Ru(OCP) complexes, (the monocarbonyl, the bis-acetonitrile and the dioxo- species) are also isolated and characterized.Science, Faculty of
Chemistry, Department of
Graduate
4
Liu, Chunjing. "Nonplanar and sterically encumbered ruthenium porphyrins and catalytic reactivity of ruthenium and manganese porphyrin complexes supported on MCM-41 /." Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19737518.
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梁嘉茵 and Ka-yan Sarana Leung. "Complexes of iminato, nitrido, imido, and hydrazido ruthenium of osmium porphyrins." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B31243307.
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Sek, Sau Yin. "The synthesis of haematoporphyrin derivative III and other novel porphyrins /." Title page, table of contents and abstract only, 1990. http://web4.library.adelaide.edu.au/theses/09PH/09phs4622.pdf.
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Zhang, Rui, and 張瑞. "Asymmetric organic oxidation by chiral ruthenium complexes containing D2 and D4 symmetric porphyrinato ligands." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B42576246.
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Sishta, Chand. "The coordination chemistry of ruthenium porphyrin complexes." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/30790.
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This thesis work reports developments in the coordination chemistry of ruthenium porphyrin complexes, both in terms of the synthesis and chemistry of new compounds, as well as the study of the solution chemistry of some previously reported complexes. The synthesis, characterization and chemistry of ten new Ru(porp) coordination complexes in the oxidation states Ru[superscript]Ⅲ and Ru[superscript]Ⅳ containing halide (Br, CI) and other axial ligands (pyridine, CH₃CN, NH₃ and SbF₆) are described in this thesis. Some additional ten Ru(porp) complexes have been studied in situ.
Measurement of the rate constants for forward and reverse reactions and the corresponding equilibrium constant by 'H NMR and UV/visible spectroscopy for the dissociation of PPh₃ ligand from Ru(OEP)L(PPh₃) (OEP is the octaethylporphyrinato dianion; L = CO, PPh₃) in C₇D₈ to generate the previously reported five-coordinate Ru(OEP)L complexes allowed for an estimation of the Ru-P bond strength (64 ± 9 kJ mol⁻¹) in these complexes. A study of PPh₃ dissociation from Ru(OEP)CO(PPh₃) in C₇D₈ and in CDC1₃ indicates that solvation effects play a major role, with CDC1₃ being more capable than C₇D₈ of solvating the Ru(OEP)CO complex. The presence of trace H₂0 in these systems was a major problem, and the coordination of H₂0 to Ru(OEP)L complexes to generate the in situ Ru(OEP)L(H₂0) complexes (L = CO, PPh₃) is described. The formation of Ru(OEP)L(H₂0) and the observed difference in the solvation of Ru(OEP)CO by C₇H₈ and CHC1₃ indicate that truly Five-coordinate species may not exist in solution. The outer-sphere oxidation of Ru [superscript]Ⅳ(OEP)PPh₃ by 0₂ to give [Ru [superscript]Ⅳ(OEP)OH]₂0 was shown to occur only in the presence of H₂0.
Mechanistic studies on the previously reported reaction of HCI with [Ru(OEP)]₂ to generate Ru^(OEP)Cl₂ (C. Sishta, M.Sc.Thesis, University of British Columbia, 1986) show that solvent plays a major role in directing this oxidation reaction. A reaction stoichiometry of 4:1 between HCI and [Ru(OEP)]₂ in C₆D₆ or C₇D₈ showed that HCI itself was the oxidant and not trace Cl₂ in HCI, as thought previously. A range of HX acids having pK[subscript]a, values in the range 38 to less than -10 (HX = H₂, MeOH, H₂0, H₂S, CH₃COOH, C₆H₅COOH, HF, CF₃COOH, HN0₃, HBF₄, HCI. HBr, and HSbF₆) were tested for reactivity with [Ru(OEP)]₂in C₆D₆; the data showed that a strong acid (pK[subscript]a < ca. 0) was necessary to initiate reactivity. The complex Ru[superscript]Ⅳ(OEP)(SbF₆)₂ was generated in situ by reacting HSbF₆ with [Ru(OEP)]₂.
In CH₂C1₂, a 1:1 stoichiometric reaction between HCI and [Ru(OEP)]₂ was observed, instantly fanning a mixture of products, tentatively formulated as Rura(OEP)H and [Ru[superscript]Ⅲ(OEP)]₂CHCl₂ based on spectroscopic data. The species proved impossible to separate. These same products were formed slowly by the reaction of [Ru(OEP)]₂ with CH₂C1₂ in the absence of HCI, and kinetic studies suggest that a direct reaction of [Ru(OEP)]₂ with CH₂C1₂ is likely, rather than reaction of [Ru(OEP)]₂ with impurities in CH₂C1₂. The product mixture generated Ru(OEP)Cl₂ upon further reaction with HCI, both in the absence and in the presence of air. The complex Ru[superscript]Ⅳ(OEP)(BF₄)₂ was generated in situ by an analogous reaction of aqueous HBF₄ with the product mixture. The required hydrogen-containing co-product from the reaction of HX (X = Br, CI) with [Ru(OEP)|₂ in C₇D₈ or CH₂C1₂ was not detected, but was shown not to be H₂.
Oxidation of Ru(porp)(CH₃CN)₂ and Ru(OEP)py₂ (py = pyridine; porp = OEP, TMP (the dianion of tetramesitylporphyrin)) by gaseous HX (X = Br, CI) in the absence of air yielded Ru[superscript]Ⅳ(porp)X₂ complexes. The new compound Ru(TMP)Br₂ was synthesized by this method using the bis(acetonitrile) precursor, and was characterized by spectroscopy; the chloride analogue Ru(TMP)Cl₂ was generated in situ.
The magnetic properties (susceptibility and moment) of Ru(OEP)Br₂ from 6 to 300 K are unlike those reported for ruthenium(IV) non-porphyrin complexes, and reveal a significant contribution from temperature-independent paramagnetism.
The reaction of Ru(OEP)X₂ (X = Br, CI) with NH₃ gave the complexes Ru[superscript]Ⅲ(OEP)X(NH₃), which upon acidification under an inert atmosphere yielded the Rum(OEP)X compounds. These Ru111 complexes were characterized by spectroscopic techniques, and the solution chemistry of the five-coordinate species Ru(OEP)X was developed: the Ru[superscript]Ⅲ(OEP)X(CH₃CN) species were also characterized. Solvation of the five-coordinate species Ru(OEP)X (X = Br, CI) was observed in coordinating solvents to form the six-coordinate species Ru(OEP)X(solvent) (solvent = py, CH₃CN and MeOH). Estimates of the equilibrium constants for the association of these ligands to Ru(OEP)X were obtained from UV/visible titration experiments in CH₂C1₂. Similarly, the equilibrium constant for the association of Br to Ru(OEP)Br to generate in situ (n-Bu)₄N⁺[Ru[superscript]Ⅲ(OEP)Br⁺₂]", was measured. Disappointingly, the complexes Ru(OEP)X were shown not to catalyze the oxidation of organic substrates such as cyclohexene.
Electrochemical and spectroelectrochemical studies of the complexes Ru(OEP)X₂ and Ru(OEP)X (X = Br, CI) showed that the Ru[superscript]Ⅳ/Ru[superscript]Ⅲ couple occurred at 480-460 mV and 950-870 mV vs. NHE, respectively, and that the probable reductant for the reaction of Ru(OEP)X₂ with NH₃ was NH₃ itself. A facile reduction of Ru(OEP)(SbF₆)₂ gave the complex Ru[superscript]Ⅲ(OEP)SbF₆, by a probable homolysis of the Ru-F bond.
The outer-sphere oxidation of Ru(OEP)py₂ by air in the presence of HX acids gave the isolated or in situ characterized complexes [Ruin(OEP)py₂]+ X" (X = CI, Br, F, BF₄). Similar oxidation of Ru(OEP)(CH₃CN)₂ formed [Ru(OEP)(CH₃CN)₂]+ Br-. Electrochenucal studies showed that 0₂ in acidic media was capable of oxidizing the Ru(OEP)(solvent)₂ complexes (solvent = py, CH₃CN) to the Ru[superscript]Ⅲ complexes, presumably generating H0₂ .Science, Faculty of
Chemistry, Department of
Graduate
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Pan, Jie. "Organometallic porphyrin based complexes for photophysical and biological application." HKBU Institutional Repository, 2016. https://repository.hkbu.edu.hk/etd_oa/331.
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This thesis focuses on the development of porphyrin-based complexes as multi-modal bio-imaging probes. Detailed studies of photophysical and biological properties were included.;In chapter 1, the general background of porphyrin and its derivatives, their structure specialty, synthetic methods, photophysical properties, and applications in biological system were described.;Curcumin-bridged porphyrin-copper complex (Por-Cu-Cur) which can permeate through the high blood-brain barrier, accumulate fast in brain tissues, and emit brilliant and stable two photon excited emission has been developed. Apart from this, Por-Cu-Cur shows high binding affinity for Ab fibrils, and decent inhibitory effect on the fibrillation of Ab1-42 peptides, as well as low toxicity to neuro-derived SK-N-SH cells in vitro and particularly in vivo in transgenic mice.;The design and synthesis of amphiphilic porphyrin linked ruthenium complexes were described. We focus on the photophysical studies of its UV-Vis absorption spectrum, fluorescence spectrum, solvatochromism, and singlet oxygen phosphorescence. The converse energy transfer mechanism of porphyrin-ruthenium complexes and zinc-porphyrin-ruthenium complexes has been clearly studied. Subcellular localization, dark cytotoxicity and photodynamic therapy has been well studied, which efficiency correspond to the energy transfer mechanism.;Based on the previous study, we would like to provide a proof-of-concept model - labelling (hot/cold) gallium in porphyrin-based complex with a short reaction time (but with high reaction yield) and aim to develop a multi-modal bioprobe for photodynamic therapy, optical imaging and positron emission tomography in one piece. An amphiphilic hot gallium-porphyrin-ruthenium compound has been synthesized (GaporRu-1) with reaction time of 15 minute and 85 % yield. The acidity of GaporRu-1 enables selective subcellular localization in lysosome. It also has an good singlet oxygen quantum yield (61.4 %), which proves its great potential for further in vivo study for as both PDT and PET agents.;Experimental details are shown in chapter 5. Including details of photophysical measurements, instrumentation and biological measurements.
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Umetani, Masataka. "Development of Novel π-Conjugated Compounds Based on Tripyrrin." Kyoto University, 2020. http://hdl.handle.net/2433/253105.
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Annapureddy, Raja Sekarreddy. "Ruthenium porphyrin catalyzed carbene mediated C-H insertion and cycloaddition reactions." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hdl.handle.net/10722/206316.
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Wang, Mingzhong, and 汪明中. "Selective alkylation of indoles catalyzed by gold (I) phosphine complexes and ruthenium (II) porphyrin complexes." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B45699501.
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Kwong, Wai-lun, and 鄺偉倫. "Anti-cancer ytterbium porphyrin and iron polypyridyl complexes: synthesis, cytotoxicity and bioinformaticsstudies." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2012. http://hub.hku.hk/bib/B48521711.
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Discovery of anti-cancer cisplatin was a great success in anti-cancer chemotherapy. Numerous analogues of cisplatin such as carboplatin and oxaliplatin, were developed to improve the clinical effectiveness. Nevertheless, the clinical uses of these platinum-based drugs are limited by the occurrence of drug-resistance, narrow range of susceptible cancer types and severe toxicity. These drawbacks have stimulated the development of other metal-based compounds with distinct mechanisms of anti-cancer action. In this study, a series of ytterbium(III) porphyrin and iron(II) polypyridyl complexes were synthesized. Their anti-cancer activities were examined. With the aid of gene expression profiling and bioinformatics analysis, the mechanisms of these anti-cancer active complexes have been examined.
A series of ytterbium(III) porphyrin complexes have been prepared and structurally characterized. An ytterbium(III) octaethylporphyrin complex (1) was found to exhibit potent anti-cancer activities with cytotoxic IC50 values down to sub-micromolar range. Complex (1) was shown to exist as a dimeric hydroxyl-bridged complex [Yb2(OEP)2(μ-OH)2] (where H2OEP = octylethylporphyrin) in CH2Cl2 and in solid state, and as monomeric [Yb(OEP)(DMSO)(OH)(OH2)] in DMSO/aqueous solution. Unlike various anti-cancer lanthanide complexes which are commonly proposed to target cellular DNA, our transcriptomics data, bioinformatics connectivity map analysis and cellular experiments altogether indicate that (1) exerts its anticancer effect through apoptosis which is highly associated with endoplasmic reticulum stress pathway.
Two iron(II) polypyridyl complexes [Fe(qpy)(CH3CN)2](ClO4)2 (Fe-1a) (qpy =2,2’:6’,2”:6”,2’”:6”’,2””-quinquepyridine) and [Fe(Py5-OH)(CH3CN)](ClO4)2 (Fe-2a) (Py5-OH = 2,6-bis[hydroxybis(2-pyridyl)methyl]pyridine) were found to display selective cytotoxicity towards cancer cell lines over a normal lung fibroblast cell line. Affymetrix oligonucleotide microarray and bioinformatics analysis suggested that the anti-cancer mechanisms of Fe-1a and Fe-2a involve apoptosis, cell cycle arrest, activation of p53 and mitogen activated protein kinase (MAPK). Complex Fe-1a induced the formation of reactive oxygen species (ROS) in a concentration-dependent manner. Both iron complexes could cleave supercoiled plasmid DNA. The cellular DNA damage induced by both complexes was confirmed by comet assay and phospho-histone protein ( -H2AX) immunofluorescence assay. Cell cycle progression analysis revealed that Fe-1a induced both S- and G2/M-phase cell cycle arrests, whereas Fe-2a induced a G0/G1-phase arrest. Apoptosis induced by both complexes was confirmed by annexin-V/SYTOX green flow cytometry analysis and western blotting. Moreover, p53 and MAPK activation were found to be associated with the induced apoptosis.
By employing the cationic porphyrin ligand, 5-(p-N-methylpyridyl)triphenylporphyrin [H2(5-MePyTPP)]+, a series of cationic metalloporphyrin complexes formulated as [M(porphyrinato)]n+ (where M = PtII, RuII, CoII or AuIII, n = 1 or 2) were prepared. The cytotoxicities of these complexes were examined. The platinum(II) and ruthenium(II) complexes were relatively non-cytotoxic towards the examined cancer cell lines with IC50 >24 μM. [CoII(5-MePyTPP)]Cl displayed a more pronounced anti-cancer activity with IC50 values between 7.48 – 17.7 μM. However, this Co(II) complex displayed poor selectivity towards the cancer cell lines compared to the normal cell line. The gold(III) porphyrin complex [AuIII(5-MePyTPP)]Cl2 showed a much higher potency (IC50 =3.01 -10.7μM) than the other [M(5-MePyTPP)]n+ prepared. By means of flow cytometry and fluorescence microscopy, [AuIII(5-MePyTPP)]Cl2 was found to induce G2/M-phase cell cycle arrest and necrotic cell death in HeLa cells.published_or_final_version
Chemistry
Doctoral
Doctor of Philosophy
14
高寶鴻 and Po-hung Ko. "Syntheses, structures and reactivities of some ruthenium, manganese and osmium complexes of non-porphyrin chelating multi-anionic ligands." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1997. http://hub.hku.hk/bib/B31235906.
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Ko, Po-hung. "Syntheses, structures and reactivities of some ruthenium, manganese and osmium complexes of non-porphyrin chelating multi-anionic ligands /." Hong Kong : University of Hong Kong, 1997. http://sunzi.lib.hku.hk/hkuto/record.jsp?B18611862.
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Li, Ka-lei Carrie. "In vitro and in vivo studies of cytotoxic and anti-angiogenic cyclometalated gold(III) and gold(III) porphyrin complexes." Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B39634577.
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Li, Ka-lei Carrie, and 李嘉莉. "In vitro and in vivo studies of cytotoxic and anti-angiogenic cyclometalated gold(III) and gold(III) porphyrin complexes." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B39634577.
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Xiao, Wenbo, and 萧文博. "Ruthenium porphyrin catalyzed nitrene insertion into C-H bonds of aromatic heterocycles, aldehydes and alkanes." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2012. http://hub.hku.hk/bib/B50434317.
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Transition metal catalyzed selective nitrene insertion into C-H bonds, which allows direct incorporation of nitrogen functionality into hydrocarbons, represents an appealing methodology for C-N bond formation, a type of bond formation of great importance in organic synthesis due to the prevalence of amino groups in biologically active natural products and pharmaceuticals. Organic azides are atom-economic and an environment-benign nitrene source. This dissertation reports the use of organic azides as a nitrene source to develop a series of protocols for C-H bond functionalization by metal-catalyzed nitrene insertion, including the diimination of indoles, the phosphoramidation of aldehydes and the amination of hydrocarbons catalyzed by ruthenium porphyrins.
Carbonylruthenium(II) porphyrin complex Ru(TTP)(CO) (TTP = meso-tetrakis(p-tolyl)porphyrinato dianion) is an effective catalyst for nitrene transfer to sp2 C-H bonds of indoles using aryl azides (ArN3) as a nitrene source. This “Ru(TTP)(CO) + ArN3” protocol selectively results in the diimination of indoles without the corresponding monoimination products being detected. In the presence of a catalyst Ru(TTP)(CO), the reactions of N-methylindole with ArN3 (Ar = 4-nitrophenyl; 3,5-bis(trifluoromethyl)phenyl), and reactions of a variety of N-substituted indoles with 4-nitrophenylazide, afford 2,3-diiminoindoles in good to excellent yields (up to 90%). This unique type of 2,3-diimination products was characterized by NMR spectroscopy, mass spectrometry and single crystal X-ray crystallography. The catalytic diimination product from N-methylindole and ArN3 (Ar = 3,5-bis(trifluoromethyl)phenyl) can also be obtained through stoichiometric reaction of N-methylindole with the corresponding bis(arylimido)ruthenium(VI) porphyrin, suggesting the possible involvement of RuVI(TTP)(NAr)2 intermediates in the Ru(TTP)(CO)-catalyzed diimination reactions.
Dichlororuthenium(IV) porphyrin complex Ru(TTP)Cl2 efficiently catalyzes the phosphoramidation of aldehydes with phosphoryl azides (RO)2P(O)N3 via a nitrene insertion into sp2 C-H bonds of aldehydes. This represents the first study on the catalytic activity of a ruthenium(IV) porphyrin towards nitrene insertion into C-H bonds. The “Ru(TTP)Cl2 + (RO)2P(O)N3” protocol exhibits high chemoselectivity and functional group tolerability. Good to excellent product yields (up to 99%) have been obtained for the Ru(TTP)Cl2-catalyzed phosphoramidation of a wide variety of aldehydes with commercially available (PhO)2P(O)N3 (DPPA) and phosphoramidation of p-tolualdehyde with various (RO)2P(O)N3 (R = Me, Et, CCl3CH2, 4-nitrophenyl). The reaction can be scaled up by adding phosphoryl azide dropwise. The use of commercially available DPPA in this protocol offers a convenient and practical method for the synthesis of N-acylphosphoramidates.
“Ru(TDCPP)Cl2 + (CCl3CH2O)2P(O)N3” (TDCPP = meso-tetrakis(2,6-dichlorophenyl)porphyrinato dianion) serves as an effective protocol for intermolecular nitrene insertion into sp3 C-H bonds of hydrocarbons. Using this protocol, a variety of hydrocarbons including cycloalkanes (such as cyclohexane) and ethylbenzenes undergo sp3 C-H amination in moderate to high yields (up to 86%). Compared with ruthenium(II) porphyrins such as Ru(TDCPP)(CO) and dirhodium carboxylates such as Rh2(OAc)4, Ru(TDCPP)Cl2 displays a markedly higher catalytic activity towards the nitrene sp3 C-H insertion with (CCl3CH2O)2P(O)N3. In addition, intramolecular nitrene insertion into sp3 C-H bond can also take place in good yields with Ru(TDCPP)Cl2 as the catalyst.published_or_final_version
Chemistry
Doctoral
Doctor of Philosophy
19
黎達成 and Tat-shing Lai. "Oxo and Imido transfer reactions mediated by ruthenium and manganese complexes containing chiral porphyrin and oxazolinyl ligands." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31237186.
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Lai, Tat-shing. "Oxo and Imido transfer reactions mediated by ruthenium and manganese complexes containing chiral porphyrin and oxazolinyl ligands /." Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19738006.
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Huang, Yan. "Synthesis, Kinetic and Photocatalytic Studies of Porphyrin-Ruthenium-Oxo Complexes." TopSCHOLAR®, 2010. http://digitalcommons.wku.edu/theses/182.
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Macrocyclic ligand-complexed transition metal-oxo intermediates are the active oxidizing species in a variety of important biological and catalytic oxidation reactions. Many transition metal catalysts have been designed to mimic the predominant oxidation catalysts in Nature, namely the cytochrome P450 enzymes. Ruthenium porphyrin complexes have been the center of the research and have successfully been utilized, as catalysts, in major oxidation reactions such as the hydroxylation of alkanes. This study focuses on kinetic and photocatalytic studies of oxidation reactions with wellcharacterized high-valent ruthenium-oxo porphyrin complexes. The trans-dioxoruthenium(VI) porphyrins have been among the best characterized metal-oxo intermediates and their involvement as the active oxidant in the hydrocarbon oxidation have been extensively studied. Following the literature known methods, a series of trans-dioxoruthenium(VI) porphyrin complexes (3a-b) were synthesized and spectroscopically characterized by UV-vis, IR and lH-NMR. In addition to the well-known chemical methods, we developed a novel photochemical approach for generation of trans-dioxoruthenium(VI) porphyrins with visible light. The fast kinetic study of two-electron oxidations of para-substituted phenyl methyl sulfides by these dioxoruthenium(VI) species was conducted by using stopped-flow spectroscopy. Results showed that the decay of trans--dioxoruthenium(VI) porphyrins in the presence of reactive sulfides follows a biexponential process. The reactivity order in the series of dioxoruthenium complexes follows TPFPP> TPP> TMP, consistent with expectations based on the electrophilic nature of high-valent metal-oxo species. Moreover, the sulfoxidation reactions are 3 to 4 orders of magnitude faster than the well-known epoxidation reactions. In addition, several ruthenium porphyrins were used as the catalysts in the competitive oxidation reactions to identify the kinetically competent oxidants during catalytic turnover conditions. The photocatalytic studies of aerobic oxidation reactions of hydrocarbons catalyzed by a bis-porphyrin-ruthenium(lV) fl-OXO dimer using atmospheric oxygen as oxygen source in the absence of co-reductants were investigated as well. The ruthenium(lV) fl-OXO bisporphyrin (6a) was found to catalyze aerobic oxidation of a variety of organic substrates efficiently. By comparison, 6a was found to be more efficient photocatalyst than the well-known 3a under identical conditions. A KIE at 298K was found to be larger than those observed in autoxidation processes, suggesting a nonradical mechanism that involved the intermediacy of ruthenium(V)-oxo species as postulated.
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Thu, Hung-yat. "Catalytic C-H bond functionalization reactions catalyzed by rhodium(III) porphyrin, palladium(II) and platinum(II) acetate complexes." View the Table of Contents & Abstract, 2006. http://sunzi.lib.hku.hk/hkuto/record/B38027872.
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Chan, Ka-ho, and 陳嘉豪. "Ruthenium-N-heterocyclic carbene and ruthenium acetylide complexes supported by macrocyclic porphyrin or tetradentate schiff base ligands : synthesis, structure and catalytic applications." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2015. http://hdl.handle.net/10722/211130.
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Thu, Hung-yat, and 杜鴻溢. "Catalytic C-H bond functionalization reactions catalyzed by rhodium(III) porphyrin, palladium(II) and platinum(II) acetatecomplexes." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B38798268.
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Iglesias, Bernardo Almeida. "Síntese e propriedades espectroscópicas e eletroquímicas de uma triazeno-porfirina." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/46/46136/tde-05092012-100130/.
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Nesta tese foi desenvolvida uma nova classe de porfirinas supramoleculares contendo um grupo (4-nitrofenil)triazeno ligado na posição meso-aril do anel porfirínico. Suas propriedades estruturais e eletrônicas foram investigadas por espectrometria de massas, espectroscopia eletrônica de absorção e emissão, cálculos teóricos semi-empíricos, ressonância magnética nuclear de 1H e 13C, voltametria cíclica e espectroeletroquímica. Efeitos eletrônicos e estruturais diferenciados foram observados quando o grupo triazeno é inserido na porfirina, fazendo com que estes novos compostos apresentem novas propriedades quanto, por exemplo, às fragmentações no estado gasoso, deslocamento batocrômico nos espectros eletrônicos de absorção, variação das intensidades relativas e nos valores dos rendimentos quânticos de fluorescência, deslocalização eletrônica nos orbitais de fronteira evidenciando as transições de transferência de carga do ânion triazenido para o anel porfirínico e variações nos processos redox dos compostos até então estudadosIn this thesis we has been developed a new class of supramolecular porphyrins containing (4-nitrophenyl)triazene group connected in the meso-aryl-position of the porphyrin ring. Their structural and electronic properties were investigated by mass spectrometry, absorption and emission electronic spectroscopy, semi-empirical theoretical calculations, nuclear magnetic resonance of 1H and 13C-NMR, cyclic voltammetry and spectroelectrochemistry. Different structural and electronic effects were observed when the unit is inserted into the triazene to porphyrin, so that these presents new properties such as, for example, to fragmentation in the gaseous state, bathocrimic shift in the electronic absorption spectra, relative intensity variation and values the fluorescence quantum yields, electron delocalization in the frontier orbitals showing the charge-transfer transitions from the triazenide anion to the porphyrin ring and changes in redox processes of compounds previously studied.
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Yao, Soledad G. "OXIDATION OF β-O-4 LIGNIN MODEL COMPOUNDS AND APPLICATION TO LIGNIN LINKAGE DEGRADATION FACILITATED BY MECHANOCHEMICAL TREATMENT AND TWO-STEP OXIDATIVE DEPOLYMERIZATION." UKnowledge, 2018. https://uknowledge.uky.edu/chemistry_etds/91.
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The oxidation of lignin model compounds was studied in conventional solvents in parallel with oxidations in ionic liquid solvents. Catalyst systems were investigated in ionic liquid solvents to determine how reaction rates and the selectivity for benzylic carbon oxidation were affected. Oxidation rates were often lower in ionic liquids than in conventional solvents ‒ as indicated by lower conversion in a standard reaction time ‒ likely due, at least in part, to the higher viscosity of ionic liquids. Mechano chemical treatment of Indulin AT kraft lignin by ball milling with KOH and toluene produced significant carbonyl functionality, among other changes. The chemical reactivity of the lignin was increased, resulting in greater lignin degradation from porphyrin oxidation followed by Baeyer-Villiger oxidation. The mechanochemical treatment produced a level of lignin oxidation that was similar to that produced by porphyrin-catalyzed oxidation. Combining mechanochemical treatment with porphyrin oxidation produced a synergistic positive effect on the depolymerization of lignin, as demonstrated by a significantly higher yield of monomers. The methyl ester of vanillic acid was obtained as the main monomeric product (after methylation), along with a small amount of methyl 5-carbomethoxyvanillate.
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Balzer, Rosana. "Estudo físico-químico e biológico dos compostos [H2(TDFSPP)] e [Zn(TDFSPP)] visando aplicação em terapia fotodinâmica (TFD)." UNIVERSIDADE ESTADUAL DE PONTA GROSSA, 2010. http://tede2.uepg.br/jspui/handle/prefix/2087.
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The properties of compounds 5, 10, 15, 20-tetrakis (2,6 difluor-5-sulfonatophenyl) sodium porphyrin, Na4[H2(TDFSPP)], and 5, 10, 15, 20-tetrakis (2,6 difluor-5-sulfonatophenyl) sodium porphyrinate zinc (II), Na4[Zn(TDFSPP)], were investigated with the objective of using them as photosensitizers in Photodynamic Therapy (PDT). LED systems were used at different emission bands, orange, green and red for irradiation of samples. Photobleaching reactions were studied through the molecular absorption analysis UV-Visible, irradiating samples with LED systems for one hour. It was observed that compounds are photostable. Oxygen singlet generation was analyzed through the uric acid test, and it was observed that the compounds generated oxygen singlet. Zinc porphyrin presented higher efficiency in the generation of the reactive species. Aggregation at different proportions of the water/ethanol system was evaluated with UV-Visible techniques and fluorescence emission. Results indicated that there was no formation of aggregates for the compounds in the conditions analyzed. The photodynamic action of compounds was analyzed through in vitro analysis with brine shrimp Artemia salina and the microorganisms Candida albicans, Escherichia coli e Staphylococcus aureus. Through the analysis of results obtained in tests with Artemia salina, it was concluded that for both compounds and for the three LED systems, the highest percentage of death occurred in tests with association of compound and irradiation, which indicates photodynamic activity in the systems employed. Results obtained in the tests to evaluate photodynamic activity of compounds for inactivation of microorganisms revealed that lighting time did not influence the number of colony forming units (UFC). The lowest UFC values were observed for the systems with association of compounds and light, that is, there was photodynamic activity. Thus, results demonstrated that the compounds present potential to be used in Photodynamic Therapy.
Neste trabalho investigaram-se as propriedades dos compostos 5, 10, 15, 20 tetrakis (2,6-difluoro-5-sulfonatofenil)porfirina de sódio, Na4[H2(TDFSPP)], e 5, 10, 15, 20 tetrakis (2,6-difluoro-5-sulfonatofenil)porfirinato zinco (II) de sódio, Na4[Zn(TDFSPP)], visando aplicabilidade como fotossensibilizadores em Terapia Fotodinâmica (TFD). Utilizaram-se sistemas de LED em diferentes faixas de emissão, alaranjado, verde e vermelho para irradiação das amostras. As reações de fotobranqueamento foram estudadas através da análise da absorção molecular UV-Visível irradiando-se as amostras com sistemas de LED durante uma hora. Observou-se que os compostos são fotoestáveis. A geração de oxigênio singlete foi analisada através do teste de ácido úrico, observando-se, que os compostos geraram oxigênio singlete, a zinco porfirina apresentou uma maior eficiência na geração da espécie reativa. A capacidade de agregação em diferentes proporções do sistema água/etanol foi analisada com as técnicas de absorção molecular UV-Visível e emissão de fluorescência, os resultados indicaram que não ocorreu formação de agregados para os compostos nas condições analisadas. A ação fotodinâmica dos compostos foi analisada através de ensaios in vitro com o microcrustáceo Artemia salina e com os micro-organismos Candida albicans, Escherichia coli e Staphylococcus aureus. Através da análise dos resultados obtidos nos testes com Artemia salina conclui-se que para os dois compostos e para os três sistemas de LED, a maior percentagem de mortalidade ocorreu nos testes com associação do composto e irradiação. Isso indica que houve atividade fotodinâmica dos sistemas utilizados. Os resultados obtidos nos testes para avaliar a atividade fotodinâmica dos compostos para inativação de micro-organismos mostraram que o tempo de iluminação não influenciou no número de unidades formadoras de colônia (UFC) de micro-organismos. Os menores valores de UFC foram observados para os sistemas com associação de composto e iluminação, ou seja, observou-se atividade fotodinâmica. Assim, os resultados demonstram que os compostos apresentam potencial para serem aplicáveis em Terapia Fotodinâmica.
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Liegel, Rodrigo Marchiori. "Aspectos da sensibilização em terapia fotodinâmica: avaliação das propriedades fotofísicas de metaloporfirinas catiônicas em meio homogêneo e micro-heterogêneo." Universidade de São Paulo, 2002. http://www.teses.usp.br/teses/disponiveis/46/46134/tde-30082018-112953/.
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Uma nova série de porfirinas catiônicas e seus respectivos metalocomplexos de Zn(II) e Cu(II) foi sintetizada. Esta nova série apresenta resíduos benzílicos substituídos ligados aos grupos piridínicos presentes nas posições meso do anel porfirínico. Estes compostos foram caracterizados e investigados utilizando várias técnicas, tais como: espectroscopia eletrônica de absorção e de emissão, RMN-1H, espectroscopia vibracional IR e raman ressonante, voltametria cíclica, espectroeletroquímica e fotólise por pulso de laser. Não foram observadas evidências de auto-agregação destes compostos em água, entretanto, estes apresentam agregação diferenciada em função da força iônica do meio, do ânion do eletrólito utilizado e do tamanho do substituinte periférico. Os potenciais de redução apresentam dependência ao caráter aceptor/doador de elétrons dos substituintes benzílicos. As porfirinas desta série apresentam parâmetros fotofísicos da mesma ordem de grandeza e comparáveis ao composto modelo 5, 10, 15,20-tetrakis(1-metilpiridínio-4-il)-porfirina (H2TMPyP) e seus metaloderivados em meio homogêneo. Em meio microhetrogêneo são observadas alterações nestes parâmetros fotofísicos, existindo um comportamento diferenciado em relação à H2TMPyP. Uma análise global dos resultados evidência que estes derivados são promissores fotossensibilizadores em sistemas de terapia fotodinâmica.A new series of cationic porphyrins and metalloporphyrins derivatives of Cu(II) and Zn(II) has been synthesized. These compounds show substituted benzylic residues attached to the piridil groups at the meso porphyrin ring positions. All porphyrins and metalloporphyrin have been fully characterized and investigated, employing approaches such as elemental analysis, electronic, vibrational and proton NMR spectroscopy, flash photolysis, and cyclic voltammetry. There is no evidence of self-aggregation of the porphyrin derivatives in pure water, however the addition of inorganic electrolytes to water solution induces aggregation in different extension, which depends on the nature of the electrolyte, the total ionic strength, and the benzylic substituent. Studies of cyclic voltammetry show that the reduction potentials are directly dependent on the electron donor/acceptor characteristics of the benzylic substituent and of the coordinated metal ion. All photophysical parameters investigated in homogeneous media are very similar through porphyrins and metalloporphyrins studied and are comparable to the model compound, the 5, 10, 15, 20-tetrakis(1-methylpyridinium-4-yl)porphyrin (H2TMPyP). Therefore, in micro-heterogeneous media, the new series of porphyrins presents some differences in the photophysical parameters, when compared to the model compound. In conclusion, the present results reveal that these new cationic porphyrins can be useful as photosensitizers in photodynamic therapy.
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Delmarre, David. "Incorporation de porphyrines dans les matrices sol-gel : études spectroscopiques et application à la détection de polluants." Cachan, Ecole normale supérieure, 1998. http://www.theses.fr/1998DENS0024.
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Le but de ce travail de thèse était de réaliser des capteurs de molécules polluantes à l'aide de porphyrines incorporées dans des matrices sol-gel. La première partie de ce travail a été consacrée a l'étude des interactions entre molécules sondes et environnement local en solution et en milieu sol-gel. Ceci a été réalisé à l'aide de porphyrines d'étain qui se sont révélés sensibles aux effets de solvant et au ph. Puis dans un second temps a l'aide de porphyrines non-métallées a cause de leur sensibilité aux variations de ph qui ont permis de calculer le ph à l'intérieur des matrices sol-gel. Une fois les interactions entre molécules sondes et matrice mieux comprises, la deuxième partie de cette thèse a consiste à étudier les interactions entre molécules sondes et polluants. Les études ont été menées dans un premier temps en solution puis en milieu sol-gel. La détection d'amine a pu être réalisée en utilisant une porphyrine de cobalt greffable. Le seuil de détection de la pyridine est de 100g/l. La deuxième partie a consisté à étudier la détection des sels de métaux lourds par des porphyrines non-métallées. Les matériaux sol-gel ne se sont pas révélés intéressants pour ce type de détection mais il a été montre que 90% des ions diffusent dans la matrice, cette propriété pourrait se révéler intéressante dans la purification de l'eau. Enfin une nouvelle structure permettant de limiter les interactions en ions et matrice semble être prometteuse pour la détection des ions métalliques.
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Li, Yan, and 李艷. "Synthesis and reactivity of carbene complexes of iron, ruthenium and osmium porphyrins." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B31245730.
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Au, Sze-man Vanessa. "Synthesis, characterization and reactivities of bis(imido)-ruthenium(vi) and -osmium(vi) porphyrins /." Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B21021478.
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Tavares, Anabela Cristóvão. "Photoinactivation of bioluminescent bacteria by porphyrinic compounds." Master's thesis, Universidade de Aveiro, 2009. http://hdl.handle.net/10773/4512.
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Mestrado em Biologia Molecular e CelularA terapia fotodinâmica antimicrobiana representa uma alternativa promissora para inactivar eficientemente microrganismos patogénicos como bactérias, vírus, fungos e protozoários. Esta terapia baseia-se na utilização de um fotossensibilizador, que quando é activado por luz, gera espécies citotóxicas que destroem as células-alvo. A inactivação fotodinâmica das células microbianas pode ocorrer através de dois mecanismos oxidativos: a via do tipo I que envolve reacções de transferência de electrões/átomos de hidrogénio do fotossensibilizador com produção de radicais iónicos e a via do tipo II que envolve a transferência de energia do fotossensibilizador para oxigénio molecular com a subsequente formação de oxigénio singuleto. Tendo em conta os mecanismos de inactivação envolvidos no processo fotodinâmico das células microbianas alvo, o aparecimento de estratégias de resistência à terapia fotodinâmica e a recuperação da viabilidade microbiana parecem ser improváveis. O objectivo deste trabalho foi investigar o(s) mecanismo(s) envolvido(s) na inactivação fotodinâmica da bactéria recombinante bioluminescente Escherichia coli, utilizando três porfirinas catiónicas meso-substituídas como fotossensibilizadores. Foi também avaliada a possibilidade de recuperação da viabilidade bacteriana após fotoinactivação e a probabilidade de desenvolvimento de resistência bacteriana à terapia fotodinâmica antimicrobiana, utilizando duas bactérias Gram-negativas: Vibrio fischeri e E. coli bioluminescente. Para investigar o(s) mecanismo(s) de fotoinactivação dos três fotossensibilizadores, foram usados vários inibidores de oxigénio singuleto e de radicais livres. Suspensões de E. coli a 107 UFC mL-1 foram distribuídas em copos esterilizados e adicionadas de porfirina à concentração final de 5.0 μM para os derivados porfirínicos Tetra-Py+-Me e Tri-SPy+-Me-PF e 0.5 μM para a porfirina Tri-Py+-Me-PF. Para testar o mecanismo do tipo I foram usados como inibidores de radicais livres L-cisteína e D-manitol (100 mM). Para testar o mecanismo do tipo II foi usada a azida sódica (100 mM) como inibidor do oxigénio singuleto. As amostras foram expostas durante 270 minutos à luz branca (4 mW cm-2). A recuperação bacteriana foi testada através de um ensaio de fotoinactivação de 270 minutos a luz branca (4 mW cm-2) expondo as as suspensões bacterianas de V. fischeri e E. coli a 5.0 μM do derivado porfirínico Tri-Py+-Me-PF e mantendo as amostras no escuro durante uma semana de incubação após o tratamento. Para avaliar o possível desenvolvimento de resistência pelas células bacterianas à terapia fotodinâmica, suspensões bacterianas de V. fischeri e de E. coli foram expostas a luz branca (4 mW cm-2) durante 25 minutos com 5.0 μM de porfirina Tri-Py+-Me-PF. Colónias isoladas de células sobreviventes após o primeiro tratamento foram novamente expostas à luz visível usando o mesmo protocolo de irradiação. Este procedimento foi repetido dez vezes para cada estirpe. Os resultados obtidos neste trabalho indicam que as reacções mediadas pelo oxigénio singuleto (mecanismo do tipo II) têm um papel predominante sobre o mecanismo do tipo I no processo de fotoinactivção da bactéria bioluminescente E. coli pelos derivados Tri-Py+-Me-PF, Tetra-Py+-Me e Tri-SPy+-Me-PF. As bactérias inactivadas através da terapia fotodinâmica não recuperaram a sua actividade após uma semana de incubação no escuro. As estirpes V. fischeri e E. coli não desenvolveram resistência a esta terapia ao fim de dez gerações. Apesar do uso de inibidores representar um método simples e eficiente para determinar qual(is) a(s) via(s) implicada(s) no processo de inactivação fotodinâmica, a escolha dos inibidores deve ter em conta a estrutura química do fotossensibilizador. A ausência de desenvolvimento de resistência bacteriana e a não recuperação da viabilidade bacteriana após uma semana de incubação indica que a terapia fotodinâmica antimicrobiana representa um método adequado para inactivar bactérias de forma eficaz usando Tri-Py+-Me-PF.
The antimicrobial photodynamic therapy seems to be a very promising possibility for the efficient inactivation of pathogenic microorganisms and it has been demonstrated in bacteria, virus, fungi and protozoa. The concept of this therapy is that a photosensitizer localized in the target cells, when activated by light, generates cytotoxic species that destroy those cells. Two oxidative mechanisms of photoinactivation are considered to be implicated in the inactivation of the target cells: the type I pathway that involves electron/hydrogen atom-transfer reactions to produce radical ions and the type II pathway that involves energy transfer to produce singlet oxygen from molecular oxygen. Having into consideration the type of damages that occur in the microorganisms after the photoinactivation process, the emergence of strategies of resistance to photodynamic therapy and microbial recovery seem to be unlikely. The aim of this work was to investigate the mechanism(s) involved in the photodynamic inactivation of a recombinant bioluminescent Escherichia coli, using three meso-substituted cationic porphyrin derivatives as photosensitizers. It was also evaluated in this study the possible recovery of bacterial viability after photodynamic inactivation and the probable development of bacterial resistance to antimicrobial photodynamic therapy using two Gram-negative bacteria: Vibrio fischeri and the bioluminescent E. coli. To investigate the mechanism(s) of photoinactivation of the three photosensitizers in study, various scavengers of singlet oxygen and of free radicals were used. Suspensions of E. coli at 107 CFU mL-1 were distributed in sterilized beakers and the porphyrins were added to a final concentration of 5.0 μM for the porphyrinic derivatives Tetra-Py+-Me and Tri-SPy+-Me-PF porphyrins and 0.5 μM for Tri-Py+-Me-PF porphyrin. To test type I mechanism L-cysteine (100 mM) and D-mannitol (100 mM) were used as free radical scavengers. To test type II mechanism, sodium azide (100 mM) was used as singlet oxygen quencher. The mixtures were exposed for 270 minutes to white light (4 mW cm-2). The bacterial recovery was tested with a photoinactivation assay of 270 minutes with white light (4 mW cm-2) exposing bacterial suspensions of V. fischeri and E. coli to 5.0 μM of the porphyrinic derivative Tri-Py+-Me-PF and maintained the samples in the dark during one week of incubation after treatment. In order to assess the possible development of resistance of bacterial cells after photoinactivation, bacterial suspensions of V. fischeri and E. coli were exposed to white light (4 mW cm-2) for 25 minutes with 5.0 μM of Tri-Py+-Me-PF. After the first irradiation period, surviving colonies were reexposed to visible light using the same irradiation protocol. This procedure was repeated ten times for each strain. The results obtained in this work suggest that singlet oxygen-mediated reactions (type II mechanism) play the most important role on the photoinactivation process of the bioluminescent E. coli by Tri-Py+-Me-PF, Tetra-Py+-Me and Tri-SPy+-Me-PF derivatives. The results also show that inactivated bacteria do not recover their viability after photoinactivation and that no resistance to photodynamic therapy appears after ten generations for V. fischeri and E. coli. Although the use of scavengers represents a simple and an efficient approach to determine which pathway(s) is(are) implicated in the photodynamic inactivation process, the choice of the scavenger must take into account the chemical structure of the photosensitizer. The antimicrobial photodynamic therapy represents an adequate method to inactivate bacteria, since bacterial cells do not recover their viability after one week of incubation nor develop resistance to the photoinactivation process using Tri-Py+-Me-PF.
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區詩敏{272b21} and Sze-man Vanessa Au. "Synthesis, characterization and reactivities of bis(imido)-ruthenium(vi) and -osmium(vi) porphyrins." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B31238117.
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Rice, M. J. "Synthetic models of cytochrome P450 and photosynthesis." Thesis, University of Cambridge, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233252.
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The work presented in this dissertation describes the prepartion and characterisation of various strapped porphyrin compounds which are designed to model cytochrome P450 and the charge separation in photosynthesis. The major part of this work is concerned with models of cytochrome P450. After a brief introduction to the philosophy of modelling, there follows a review of work on the enzyme and various compounds which are designed to reproduce the enzymic characteristics. The synthesis of two singly bridged porphyrins is reported. These incorporate a pendent methyl ester in the centre of the strap and aim to mimic the proposed acylation step in the catalytic cycle. Evaluation as models was performed by a series of experiments involving the addition of potassium superoxide to the manganese complexes of these compounds. Characterisation of the mode of reactivity required the use of many physical techniques and necessitated the synthesis of a radio-labelled sample of one of the porphyrins. The results obtained suggest that superoxide binds preferentially to the bridge-free face of the macrocycle. Doubly bridged analogues of the above models were prepared which force the two faces of the porphyrin to be equivalent. Superoxide binding studies indicated a different mode of reactivity to the singly bridged models, for one of the compounds, and experiments to distinguish between possible interpretations of the results are suggested. A crown ether thiolate doubly bridged porphyrin was prepared as a model for the carbon monoxide complex of the enzyme. This was characterised by ultraviolet spectroscopy and attempts to produce a stable crystalline adduct are described. The remaining part of this work concerns a model for the charge separation process in photosynthesis. A discussion of natural systems and previous models is followed by a description of a tetraene pyromellitimide doubly bridged porphyrin, which shows significant quenching of the porphyrin fluorescence.
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Zhou, Congying. "Ruthenium porphyrins and dirhodium (II, II) carboxylates catalyzed ylide-mediated cycloadditions and carbenoid transfer reactions." Click to view the E-thesis via HKUTO, 2004. http://sunzi.lib.hku.hk/hkuto/record/B31046484.
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Zhou, Congying, and 周聰穎. "Ruthenium porphyrins and dirhodium (II, II) carboxylates catalyzed ylide-mediated cycloadditions and carbenoid transfer reactions." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B31046484.
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Cromer, Rémy. "Porphyrines n-substituees : modelisation de l'inhibition d'hemoproteines." Université Louis Pasteur (Strasbourg) (1971-2008), 1986. http://www.theses.fr/1986STR13015.
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Migration cobalt-azote des groupements : phenyl et styryl. L'etude des reactions de migration dans les porphyrines de cobalt(iii) aryliques a justifie l'utilisation de ces dernieres pour modeliser l'hydrazinolyse des hemoproteines. Les porphyrines de cobalt(iii) aryliques ont un comportement analogue a celui des porphyrines de fer(iii) aryliques. Oxydation des styryl -co(iii) porphyrines. Mecanisme de reaction. Extension de cette reaction a la cyclisation en serie arylique qui permet la synthese de la premiere porphyrine n,n'-(phenylene-1,2) analogue du produit d'inhibition suicide obtenu apres activation de l'amino-1 benzotriazole par divers enzymes a cytochrome p-450
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Hatcher, Jancie Stinecipher. "Synthesis, characterization, and monolayer formation of sulfur-substituted tetraphenylporphyrins." Thesis, Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/29977.
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Leung, Ka-yan Sarana. "Complexes of iminato, nitrido, imido, and hydrazido ruthenium of osmium porphyrins /." Hong Kong : University of Hong Kong, 2002. http://sunzi.lib.hku.hk/hkuto/record.jsp?B25212072.
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Zhang, Rui. "Asymmetric organic oxidation by chiral ruthenium complexes containing D2 and D4 symmetric porphyrinato ligands." Click to view the E-thesis via HKUTO, 2000. http://sunzi.lib.hku.hk/hkuto/record/B42576246.
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Miyahara, Tomoo. "Theoretical studies on the photochemistry of porphyrins and biologically important compounds." 京都大学 (Kyoto University), 2003. http://hdl.handle.net/2433/148879.
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Sun, Wai-yin Raymond, and 辛偉賢. "The antitumor and antiviral properties of gold (III) porphyrins and their related complexes." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B31245973.
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Boukhris, Abdallah. "Étude par diffraction des rayons X des porphyrines de gallium, germanium et indium, synthons potentiels de conducteurs électriques unidimensionnels." Nancy 1, 1986. http://www.theses.fr/1986NAN10038.
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Étude des composés GA(OEP)(SO::(3)CH::(3)), GA(OEP)N::(3), GE(TPMEPP)(N::(3))::(2), GE(OEP)F::(2) et (OEP) IN-MN(CO)::(5). Caractérisation des groupements azido dans les porphyrines de gallium et de germanium. Première liaison simple métat-métal dans la série des métalloporphyrines. Dopage de fluoro-octaethylporphyrines de gallium et d'octaméthylporphyrines de nickel par l'iode moléculaire. Incommensurabilité des réseaux iode et porphyrine, caractère polymérique des métalloporphyrines. Étude de la conductivité électrique
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Carver, Aaron Dalnamath. "Selective Oxidations by Iron(III) Porphyrins and Iron(III) Corroles." TopSCHOLAR®, 2014. http://digitalcommons.wku.edu/theses/1395.
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The selective oxidation of organic compounds represents a leading technology for chemical industries. They are used in chemical synthesis in the pharmaceutical and petrochemicals industries, and possible the decontamination of harmful substances. However, oxidations reaction are among the most challenging processes to control. Many stoichiometric oxidants with heavy metals are expensive, or toxic maybe both, and therefore unfeasible to be utilized. The ideal processes for catalytic oxidation would use molecular oxygen or hydrogen peroxide as the primary oxygen source, with transition metal catalysts to mimic the predominant oxidation catalysts in Nature, the cytochrome P450 enzymes. This study focuses on the synthesis of porphyrin and corrole macrocyclic ligands and the corresponding iron(III) complexes which are fully characterized by UV-vis, GC/MS, and NMR spectroscopies. In this work, the potential of catalytic oxidation reactions towards organic sulfides by these metal complexes were studied. The iron(III) porphyrin and iron(III) corrole catalysts have shown excellent activity and selectivity for sulfoxidation reactions. Various reaction conditions and environmental effects were investigated including solvent, axial ligands, water, amounts of oxygen source, and substrate scope. The optimal conditions were determined for iron(III) porphyrin/ corrole-catalyzed sulfoxidations with PhI(OAc)2 as the mild oxygen source. Competitive catalytic oxidation of substituted thioanisoles versus thioanisole by iron(III) corrole with PhI(OAc)2 were studied. The spectral studies of iron(III) corrole with PhI(OAc)2 in the presence of organic sulfide showed that a well-known diiron(IV)-μ-oxo biscorrole was formed with a second-order rate constant of k2= (3.5 ± 0.3)×103 M-1·s-1. A catalytic cycle was proposed on the basis of the mechanistic study, suggesting a highly reactive iron(V)-oxo corrole as the active oxidizing intermediate.
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Renko, Zafiarisoa Dolor. "Synthèse totale de porphyrines protégées sur leurs deux faces (Porphyrines "Gyroscopes")." Paris 6, 1986. http://www.theses.fr/1986PA066274.
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La synthèse d'une nouvelle génération de porphyrines protégées sur leurs deux faces a été réalisée. Il s'agit d'un dérivé d'une octamethylporphyrine substituée en ses positions méso alpha et gamma par deux groupes phényles eux-mêmes fonctionnalises en position ortho et ortho par des anses peptidiques d'acides aminés optiquement actifs. L'une des anses comporte une pyridine. La synthèse totale de cette porphyrine a été effectuée en vue d'obtenir de nouveaux modèles d'hémoprotéines et de nouveaux catalyseurs d'époxydation asymétrique.
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Azevedo, Vítor Manuel Madureira. "Lipidomic study of the red marine macroalgae as source of bioactive compounds." Master's thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/17513.
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Mestrado em Mestre em Bioquímica, ramo da Bioquímica ClínicaMarine macroalgae, or seaweeds, have gained an increased interest in recent times for the use in various biotechnological applications, due to the added-value of their chemical constituents. Among them, glycolipids and phospholipids display several commercial applications in a wide spectrum of industries, such as food, pharmaceutical and cosmetic. In an effort to further understand the lipid composition of macroalgae, the present work reports, for the first time, the isolation and characterization of the polar lipid profile of the red macroalgae Porphyra dioica cultivated on a land-based integrated multi-trophic aquaculture (IMTA) system, using a lipidomic-based approach employing hydrophilic interaction liquid chromatography-eletrospray ionization mass spectrometry (HILIC-ESI-MS). The fatty acid profile of this species of seaweed was also determined, accounting for season variability and its life cycle. The polar lipid profile of P. dioica revealed the presence of over 69 molecular species, corresponding to glycolipids (sulfoquinovolsyldiacylglycerols, sulfoquinovosylmonoacylglycerols, digalactosyldiacylglycerols) and glycerophospholipids (lyso- and phosphatidylglycerols), lyso- and phosphatidylcholines), as well as phytyl derivatives. Some of these polar lipids contain polyunsaturated fatty acids (PUFAs), namely arachidonic acid (C20:4) and eicosapentaenoic acid (C20:5), thus revealing the ability of P. dioica to biosynthesize this long chain PUFAs. P.dioica from the winter season revealed to be richer in PUFA content, accounting for 37.0% of total fatty acid (TFA) content, as opposed to P. dioica from the summer season (25.0% of TFA content). Eicosapentaenoic acid (EPA) content was revealed to be being significantly higher in the winter season (25.2% of TFA content). The diploid sporophyte conchocelis phase of P. dioica showed to possess the highest amount of PUFAs (47.0% of TFA content), with arachidonic acid being the most abundant fatty acid (21.2% of TFA content). Several of the lipids identified have been reported to possess nutritional and health benefits, thus allowing the valorisation of P. dioica from IMTA as a source of bioactive compounds, adequate for the use in a wide range of different applications and as a functional food, rich in omega-3 fatty acids.
As macroalgas têm vindo a ganhar um interesse cada vez maior para o uso em diversas aplicações biotecnológicas, devido ao valor acrescentado dos seus diferentes constituintes. Entre estes, os glicolípidos e os fosfolípidos podem ser usados comercialmente em diferentes indústrias, tais como as indústrias alimentar, farmacêutica e cosmética. Com o objetivo de compreender melhor a composição lipídica das macroalgas, o presente trabalho relata, pela primeira vez, a caracterização do perfil de lípidos polares da macroalga vermelha Porphyra dioica, cultivada num sistema de aquacultura multi-trófica integrada (IMTA), utilizando para esse fim uma abordagem lipidómica baseada na espectrometria de massa (HILIC-ESI-MS). Foi também determinado o perfil de ácidos gordos da referida espécie de alga, tendo em consideração a variabilidade sazonal e o seu ciclo de vida. O perfil de lípidos polares da alga P. dioica revelou a presença de mais de 69 espécies moleculares diferentes, correspondendo a classes de glicolípidos (sulfoquinovosildiacilgliceróis, sulfoquinovosilmonoacilgliceróis e digalactosildiacilgliceróis), fosfolípidos (liso- e fosfatidilglicerol, liso- e fosfatidilcolinas) e derivados fitil. Alguns destes lípidos polares contêm ácidos gordos polinsaturados (PUFAs) na sua composição, nomeadamente o ácido araquidónico (C20:4) e ácido eicosapentaenóico (C20:5), revelando, assim, a capacidade da alga P. dioica em biossintetizar este tipo de ácidos gordos polinsaturados de cadeia longa. Considerando a variação sazonal do conteúdo em ácidos gordos, a P. dioica cultivada no inverno revelou ser mais rica em PUFAs, correspondendo a 37.0% do conteúdo total de ácidos gordos, contrariamente à P. dioica cultivada no verão (25.0%). O conteúdo em ácido eicosapentaenóico (EPA) é significativamente maior na estação de inverno (25.2%). O perfil em ácidos gordos também variou com o ciclo de vida P. dioica, sendo que na fase de conchocelis a quantidade de PUFA é significativamente mais elevada (47.0% de conteúdo de ácidos gordos), sendo o ácido araquidónico o ácido gordo mais abundante (21.2% de conteúdo de ácidos gordos).Várias classes de lípidos polares foram identificados como possuindo benefícios nutricionais e para a saúde, permitindo assim a valorização da alga vermelha P. dioica produzida em IMTA como uma fonte de compostos bioativos, adequados para o uso numa grande variedade de aplicações como um alimento funcional, rica em ácidos gordos polinsaturados ómega-3.
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Belair, Jeffery P. "The Photophysical Characterization of N-Confused Tetraphenylporphyrin and the Characterization of Zinc N-Confused Tetraphenylporphyrin." University of Akron / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=akron1133950418.
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Öztek, Muzaffer Tonguç. "The study of three different layered structures as model systems for hydrogen storage materials." Doctoral diss., University of Central Florida, 2011. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5001.
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The strength and success of the hydrogen economy relies heavily on the storage of hydrogen. Storage systems in which hydrogen is sequestered in a solid material have been shown to be advantageous over storage of hydrogen as a liquid or compressed gas. Many different types of materials have been investigated, yet the desired capacity and uptake/release characteristics required for implementation have not been reached. In this work, porphyrin aggregates were investigated as a new type of material for hydrogen storage. The building blocks of the aggregates are porphyrin molecules that are planar and can assume a face to face arrangement that is also known as H-aggregation. The H-aggregates were formed in solution, upon mixing of aqueous solutions of two different porphyrins, one carrying positively charged and the other one carrying negatively charged functional groups. The cationic porphyrin used was meso-tetra(4-N,N,N-trimethylanilinium) porphine (TAP) and it was combined with four different anionic porphyrins, meso-tetra(4-sulfonatophenyl)porphine (TPPS), meso-tetra(4-carboxyphenyl) porphine (TCPP), Cu(II) meso-tetra(4-carboxyphenyl) porphine, and Fe(III) meso-tetra(4-carboxyphenyl) porphine. The force of attraction that held two oppositely charged porphyrin molecules together was electrostatic attraction between the peripheral groups. Solid state aggregates were successfully isolated either by solvent evaporation or by centrifuging and freeze drying. TCPP-TAP and Cu(II)TCPP-TAP aggregates were shown to interact with hydrogen starting from 150 [degrees]C up to 250 [degrees]C. The uptake capacity was about 1 weight %. Although this value is very low, this is the first observation of porphyrin aggregates absorbing hydrogen. This opened the way for further research to improve hydrogen absorption properties of these materials, as well as other materials based on this model.; Two other materials that are also based on planar building blocks were selected to serve as a comparison to the porphyrin aggregates. The first of those materials was metal intercalated graphite compounds. In such compounds, a metal atom is placed between the layers of graphene that make up the graphite. Lithium, calcium and lanthanum were selected in this study. Theoretical hydrogen capacity was calculated for each material based on the hydriding of the metal atoms only. The fraction of that theoretical hydrogen capacity actually displayed by each material increased from La to Ca to Li containing graphite. The weight % hydrogen observed for these materials varied between 0.60 and 2.0 %. The other material tested for comparison was K[sub x]MnO[sub2], a layered structure of MnO[sub2] that contained the K atoms in between oxygen layers. The hydrogen capacity of the K[sub x]MnO[sub2] samples was similar to the other materials tested in the study, slightly above 1 weight %. This work has shown that porphyrin aggregates, carbon based and manganese dioxide based materials are excellent model materials for hydrogen storage. All three materials absorb hydrogen. Porphyrin aggregates have the potential to exhibit adjustable hydrogen uptake and release temperatures owing to their structure that could interact with an external electric or magnetic field. In the layered materials, it is possible to alter interlayer spacing and the particular intercalates to potentially produce a material with an exceptionally large hydrogen capacity. As a result, these materials can have significant impact on the use of hydrogen as an energy carrier.ID: 029809891; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Thesis (Ph.D.)--University of Central Florida, 2011.; Includes bibliographical references (p. 86-101).
Ph.D.
Doctorate
Chemistry
Sciences
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Lesieur, Pierre. "Etude de l'orientation moléculaire dans les films de Langmuir-Blodgett." Paris 6, 1986. http://www.theses.fr/1986PA066290.
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Ce travail constitue une caractérisation des films de Langmuir-Blodgett par résonance paramagnétique électrique et par diffusion Raman résonante en lumière polarisée. Les films sont constitués de multicouches, mixtes ou alternées, de porphyrines amphiphiles et d'acide docosanoïque. Le sujet porte sur l'orientation des macrocycles porphyriniques par rapport au substrat supportant les couches
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Veyrat, Marc. "Synthèse de porphyrines et métalloporphyrines chirales dérivées d'aldéhydes alicycliques : application à la catalyse d'époxydation asymétrique d'alcènes." Université Joseph Fourier (Grenoble ; 1971-2015), 1994. http://www.theses.fr/1994GRE10191.
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De nombreux prototypes de porphyrines comportant des superstructures chirales elaborees ont ete synthetises au cours de la derniere decennie, en vue de l'utilisation de leurs complexes metalliques comme catalyseurs d'epoxydation asymetrique des alcenes. L'utilite de ces composes est en general limitee, du fait de leur synthese laborieuse et des etapes de separation d'isomeres qu'elle comporte. L'approche originale decrite dans cette these fournit des catalyseurs asymetriques de structure plus simple, d'obtention plus facile, et donc potentiellement plus utiles. Une etude preliminaire, centree sur la preparation de metallo-mesotetrakis(cyclohexyl)porphyrines, etablit les bases de la methodologie synthetique. Les nouvelles porphyrines chirales sont ensuite obtenues, en une seule etape, par condensation du pyrrole avec des aldehydes alicycliques chiraux facilement disponibles, tels que le (1r)-(-)-myrtenal ou l'ester methylique de l'acide (1r)-cis-hemicaronaldehydique. Dans le second cas, la porphyrine produite consiste exclusivement en l'isomere bb dont la symetrie d#2 est la plus appropriee a l'enantioselectivite recherchee. De fait, l'exces enantiomerique observe pour l'epoxydation de divers alcenes atteint 70% dans le meilleur cas (dihydronaphtalene). Des etudes structurales par rmn a temperature variable et par diffraction des rayons x permettent d'etablir une relation entre la rigidite stereochimique de la porphyrine chirale et l'induction asymetrique observee