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Photocytotoxic activity of a nitrosyl phthalocyanine ruthenium complex - A system capable of producing nitric oxide and singlet oxygen

CARNEIRO, Zumira Aparecida; MORAES, Juliana Cristina Biazzotto de; RODRIGUES, Fernando Postalli; LIMA, Renata Galvao de; CURTI, Carlos; ROCHA, Zenis Novaes da; PAULO, Michele; BENDHACK, Lusiane Maria; TEDESCO, Antonio Claudio; FORMIGA, Andre Luiz Barboza;
Fonte: ELSEVIER SCIENCE INC Publicador: ELSEVIER SCIENCE INC
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
368.94625%
The synthesis, structural aspects, pharmacological assays, and in vitro photoinduced cytotoxic properties of [Ru(NO)(ONO)(pc)] (pc = phthalocyanine) are described. Its biological effect on the B16F10 cell line was studied in the presence and absence of visible light irradiation. At comparable irradiation levels, [Ru(NO) (ONO)(pc)] was more effective than [Ru(pc)] at inhibiting cell growth, suggesting that occurrence of nitric oxide release following singlet oxygen production upon light irradiation may be an important mechanism by which the nitrosyl ruthenium complex exhibits enhanced biological activity in cells. Following visible light activation, the [Ru(NO)(ONO)(pc)] complex displayed increased potency in B16F10 cells upon modifications to the photoinduced dose; indeed, enhanced potency was detected when the nitrosyl ruthenium complex was encapsulated in a drug delivery system. The liposome containing the [Ru(NO)(ONO)(pc)] complex was over 25% more active than the corresponding ruthenium complex in phosphate buffer solution. The activity of the complex was directly proportional to the ruthenium amount present inside the cell, as determined by inductively coupled plasma mass spectroscopy. Flow cytometry analysis revealed that the photocytotoxic activity was mainly due to apoptosis. Furthermore...

Aerobic oxidation of monoterpenic alcohols catalyzed by ruthenium hydroxide supported on silica-coated magnetic nanoparticles

COSTA, Vinicius V.; JACINTO, Marcos J.; ROSSI, Liane M.; LANDERS, Richard; GUSEVSKAYA, Elena V.
Fonte: ACADEMIC PRESS INC ELSEVIER SCIENCE Publicador: ACADEMIC PRESS INC ELSEVIER SCIENCE
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
370.23098%
Ruthenium hydroxide supported on silica-coated magnetic nanoparticles was shown to be an efficient heterogeneous catalyst for the liquid-phase oxidation of a wide range of alcohols using molecular oxygen as a sole oxidant in the absence of co-catalysts or additives. The material was prepared through the loading of the amino modified support with ruthenium(III) ions from an aqueous solution of ruthenium(III) chloride followed by treatment with sodium hydroxide to form ruthenium hydroxide species. Characterizations suggest that ruthenium hydroxide is highly dispersed on the support surface, with no ruthenium containing crystalline phases being detected. Various carbonylic monoterpenoids important for fragrance and pharmaceutical industries can be obtained in good to excellent yields starting from biomass-based monoterpenic alcohols, such as isobomeol, perillyl alcohol, carveol, and citronellol. The catalyst undergoes no metal leaching and can be easily recovered by the application of an external magnet and re-used. (C) 2011 Elsevier Inc. All rights reserved.; CNPq; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); CAPES; FAPESP; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); FAPEMIG; Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG); INCT-Catalise (Brazil); INCT-Catalise (Brazil)

Catálise oxidativa de clusters de rutênio e porfirinas supramoleculares; Oxidative catalysis of ruthenium clusters and supramolecular porphyrins

Nunes, Genebaldo Sales
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 11/07/2005 PT
Relevância na Pesquisa
368.94625%
A atividade catalítica de clusters trigonais de acetato de rutênio e porfirinas supramoleculares contendo quatro unidades de clusters periféricos ou complexos de bis(bipiridina)rutênio, na oxidação de substratos orgânicos por iodosil-benzeno ou terc-butil-hidroperóxido, é abordada nesta tese. Foram feitos estudos cinéticos para elucidar o mecanismo de catálise, com especial destaque para duas espécies supramoleculares isoméricas representadas por Mn(3-TRPyP) ou Mn(4-TRPyP), nos quais os complexos de bis(bipiridina)(cloro)rutênio se coordenam à tetrapiridilporfirina através das posições meta ou para da ponte piridínica, respectivamente. Além da maior seletividade proporcionada pelos catalisadores supramoleculares, a substituição do íon cloreto pela água nos complexos periféricos de rutênio, intensificou a atividade catalítica, gerando novos sítios ativos, do tipo Ru(IV)=O. Também foram estudados clusters trinucleares de rutênio, altamente reativos, no estado Ru(III)Ru(IV)Ru(IV)=O. Estes foram gerados eletroquimicamente em solução aquosa, apresentando pronunciada atividade catalítica na oxidação do alcool benzílico. Finalmente, uma espécie dimérica de cluster, ainda inédita, com ponte oxo, foi caracterizada e investigada do ponto de vista catalítico.; The catalytic activity of trinuclear ruthenium clusters and supramolecular tetrapyridylporphyrins containing four peripheral cluster units or bis(bipyridine)ruthenium complexes...

Sistemas de liberação contendo um complexo nitrosilo de rutênio como doador de NO para a terapia fotodinâmica tópica; Drug delivery system containig a nitrosyl ruthenium complex intended for topical photodinamyc therapy

Santana, Danielle Cristine Almeida Silva de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 14/06/2010 PT
Relevância na Pesquisa
371.2638%
O NO é uma molécula endógena, envolvida em numerosos processos fisiológicos e patológicos. Diversas substâncias capazes de liberar NO in vivo têm sido estudadas, incluindo os complexos nitrosilo de rutênio, como o [Ru(terpy)(bdqi-COOH)NO](PF6)3, capaz de liberar NO após fotoestímulo. Considerando que as funções específicas do NO dependem de sua localização e cinética de liberação, e que a sua aplicação tópica pode evitar possíveis efeitos colaterais, o objetivo deste trabalho foi estudar a absorção cutânea passiva e iontoforética do complexo [Ru(bdqi-COOH)(terpy)(NO)](PF6)3, assim como a do NO dele liberado. A atividade citotóxica do complexo também foi estudada em cultura de células tumorais A431 na presença e ausência de luz e de corrente elétrica. Foi desenvolvido e validado um método analítico para a quantificação do complexo de rutênio por CLAE e estudos de pré-formulação de solubilidade, coeficiente de partilha e estabilidade do complexo foram realizados antes dos estudos de penetração cutânea. O complexo de rutênio manteve-se estável em solução aquosa a temperatura ambiente até o período de 48h, mas instável em contato com a pele inteira, com a degradação de 61% após 8h. Em contato apenas com o estrato córneo (EC)...

Síntese e caracterização de complexos híbridos de rutênio e medida da atividade biológica contra Trypanosoma cruzi; Synthesis and characterization of hybrid complexes of ruthenium and measurement of biological activity against Trypanosoma cruzi

Santos, Maíta
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 06/07/2012 PT
Relevância na Pesquisa
368.94625%
Segundo a Organização Mundial de Saúde (OMS), mais de um bilhão de pessoas estão infectadas com uma ou mais doenças tropicais endêmicas encontradas especialmente entre as populações pobres da África, Ásia e América Latina. Nos últimos 25 anos, apenas 1% de todos os medicamentos desenvolvidos no mundo foram destinados ao tratamento de doenças tropicais, como a doença de Chagas. A doença de Chagas é causada por um protozoário intracelular, o Trypanosoma cruzi, e atualmente apenas dois compostos tem sido empregados para tratamento etiológico da doença de Chagas: nifurtimox e benznidazol. Entretanto, ambos os compostos apresentam considerável toxicidade sistêmica. Nesse contexto, o objetivo do presente trabalho foi desenvolver complexos híbridos de rutênio, com potencial atividade tripanocida, que possam atuar com maior eficácia em sítios biológicos específicos do Trypanosoma cruzi e com reduzida toxicidade sistêmica. Para tal efeito, moléculas com conhecida atividade microbicida como derivados aminoglicosídeos, óxido nítrico e benznidazol foram coordenados a complexos de rutênio originando as espécies Ru(desoxiestreptamina), Ru(neamina), cis-[Ru(bpy)2(Bz)(NO)](PF6)3 e cis-[Ru(NO2)(bpy)2(Bz)]PF6. Os complexos foram caracterizados por espectroscopia de absorção no UV-vis e FTIR...

Reatividade de ésteres de fósforo(III) em tetraaminas de rutênio; Reactivity of phosphorus(III) esters in ruthenium tetraammines

Truzzi, Daniela Ramos
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 19/02/2014 PT
Relevância na Pesquisa
368.94625%
As alterações na reatividade de ésteres de fósforo(III) promovidas pela coordenação ao centro metálico de rutênio(II) e o mútuo efeito e influência trans entre ésteres de fósforo(III) e ligantes π-aceptores (NO+ e CO) foram o foco deste trabalho. Dados de Ressonância Magnética Nuclear adquiridos em função do tempo sugerem que a coordenação de fosfitos ao centro de rutênio(II) estabiliza essas moléculas com respeito à reações de hidrólise e de oxidação. Esta estabilização é maior quando a coordenação se dá no fragmento trans-[Ru(H2O)(NH3)4]2+ do que no trans-[Ru(NO)(NH3)4]3+ devido à menor competição pelos elétrons 4dπ(RuII) no aqua do que nos nitrosilos complexos. A correlação linear entre os valores numéricos das constantes de hidrólise dos alquil fosfitos nos complexos trans-[Ru(NO)(NH3)4P(III)]3+ (P(III) = P(OC3H7)3, P(OC4H9)3, P(OC2H5)3 e P(OH)(OC2H5)2) e os valores numéricos de δ13C mostram que a hidrólise de fosfitos coordenados a Ru(II) ocorre preferencialmente via mecanismo de Michaelis Arbusov. Apenas o nitrosilo em que P(III) = P(OCH3)3 não apresentou esta correlação, indicando que, neste caso, provavelmente a hidrólise se dá via mecanismo de Asknes. Os complexos trans-[Ru(NO)(NH3)4(P(O)(OH)2)]ZnCl4 e trans-[Ru(CO)(NH3)4(P(OH)3)]ZnCl4 foram isolados e caracterizados por Raio-X...

Photocytotoxic activity of a nitrosyl phthalocyanine ruthenium complex - A system capable of producing nitric oxide and singlet oxygen

CARNEIRO, Zumira Aparecida; MORAES, Juliana Cristina Biazzotto de; RODRIGUES, Fernando Postalli; LIMA, Renata Galvao de; CURTI, Carlos; ROCHA, Zenis Novaes da; PAULO, Michele; BENDHACK, Lusiane Maria; TEDESCO, Antonio Claudio; FORMIGA, Andre Luiz Barboza;
Fonte: ELSEVIER SCIENCE INC Publicador: ELSEVIER SCIENCE INC
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
368.94625%
The synthesis, structural aspects, pharmacological assays, and in vitro photoinduced cytotoxic properties of [Ru(NO)(ONO)(pc)] (pc = phthalocyanine) are described. Its biological effect on the B16F10 cell line was studied in the presence and absence of visible light irradiation. At comparable irradiation levels, [Ru(NO) (ONO)(pc)] was more effective than [Ru(pc)] at inhibiting cell growth, suggesting that occurrence of nitric oxide release following singlet oxygen production upon light irradiation may be an important mechanism by which the nitrosyl ruthenium complex exhibits enhanced biological activity in cells. Following visible light activation, the [Ru(NO)(ONO)(pc)] complex displayed increased potency in B16F10 cells upon modifications to the photoinduced dose; indeed, enhanced potency was detected when the nitrosyl ruthenium complex was encapsulated in a drug delivery system. The liposome containing the [Ru(NO)(ONO)(pc)] complex was over 25% more active than the corresponding ruthenium complex in phosphate buffer solution. The activity of the complex was directly proportional to the ruthenium amount present inside the cell, as determined by inductively coupled plasma mass spectroscopy. Flow cytometry analysis revealed that the photocytotoxic activity was mainly due to apoptosis. Furthermore...

Aerobic oxidation of monoterpenic alcohols catalyzed by ruthenium hydroxide supported on silica-coated magnetic nanoparticles

COSTA, Vinicius V.; JACINTO, Marcos J.; ROSSI, Liane M.; LANDERS, Richard; GUSEVSKAYA, Elena V.
Fonte: ACADEMIC PRESS INC ELSEVIER SCIENCE Publicador: ACADEMIC PRESS INC ELSEVIER SCIENCE
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
370.23098%
Ruthenium hydroxide supported on silica-coated magnetic nanoparticles was shown to be an efficient heterogeneous catalyst for the liquid-phase oxidation of a wide range of alcohols using molecular oxygen as a sole oxidant in the absence of co-catalysts or additives. The material was prepared through the loading of the amino modified support with ruthenium(III) ions from an aqueous solution of ruthenium(III) chloride followed by treatment with sodium hydroxide to form ruthenium hydroxide species. Characterizations suggest that ruthenium hydroxide is highly dispersed on the support surface, with no ruthenium containing crystalline phases being detected. Various carbonylic monoterpenoids important for fragrance and pharmaceutical industries can be obtained in good to excellent yields starting from biomass-based monoterpenic alcohols, such as isobomeol, perillyl alcohol, carveol, and citronellol. The catalyst undergoes no metal leaching and can be easily recovered by the application of an external magnet and re-used. (C) 2011 Elsevier Inc. All rights reserved.; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Synthesis and Characterization of Ruthenium Amidinate Complexes as Precursors for Vapor Deposition

Gordon, Roy Gerald; Lim, Booyong S.; Li, Zhengwen; Aaltonen, Titta; Li, Huazhi
Fonte: Bentham Science Publicador: Bentham Science
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
368.94625%
Three new ruthenium amidinate complexes were prepared: tris(diisopropylacetamidinato)-ruthenium(III), Ru(iPrNC(Me)NiPr)3 4; bis(diisopropyl-acetamidinato)ruthenium(II) dicarbonyl, Ru(iPrNC(Me)NiPr)2(CO)2 5; and bis(ditert- butylacetamidinato)ruthenium(II) dicarbonyl, Ru(tBuNC(Me)NtBu)2(CO)2 6. They have been synthesized and characterized by 1H NMR, TG and X-ray structure analysis. These three complexes were found to be monomeric and air stable. Compound 6 was found to have sufficient volatility and thermal stability for use in chemical vapor deposition (CVD) and atomic layer deposition (ALD) of ruthenium metal films.; Chemistry and Chemical Biology

Avaliação do Potencial Citotóxico, Genotóxico e Antitumoral do Ditionato de cis-Tetraamino(oxalato)rutênio(III) em Diferentes Linhagens Celulares; Assessment of the Potential genotoxic and the Antitumor Ditionato Tetraamino cis-(oxalate) ruthenium (III) in Different Cell lines

PEREIRA, Flávia de Castro
Fonte: Universidade Federal de Goiás; BR; UFG; Mestrado em Biologia; Ciências Biolóicas Publicador: Universidade Federal de Goiás; BR; UFG; Mestrado em Biologia; Ciências Biolóicas
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
375.96766%
Despite the resounding success of cisplatin and closely related platinum antitumor agents, the movement of other transition-metal antitumor agents toward the clinic has been exceptionally slow. Non-Platinum chemotherapeutic metallopharmaceuticals hold much promise for the future, and needs to be actively explored in a large variety of tumor types in combination therapies. The preparations of metallocomplexes with potential antitumor activity has been one of the main targets of transition metal chemistry since Rosenberg s discovery of cisplatin cisdiamminedichloridoplatinum (II), cis-[Pt(NH3)2Cl2]} cytotoxic activity in the 1960s. In 1978, cisplatin was approved as the first platinumbased drug for the oncology treatment, although several negative side-effects (nephrotoxicity, neurotoxicity, nausea, etc.) had been induced on treated patients. Nevertheless, cisplatin was followed by carboplatin {cis-diammine-1,1´ - yclobutanedicarboxylateplatinum(II), [Pt(NH3)2(cbdc)], approved in 1985} and oxaliplatin 1R,2Rdiamminocyclohexaneoxalatoplatinum(II), [Pt(dach)(ox)], approved in 1996}, which met requirements of improving antitumor activity and reducing disadvantages of cisplatin, carboplatin and oxaliplatin represent the second, and third platinum-based drug generations...

Estudo do potencial citotóxico, genotóxico e do mecanismo de morte celular de complexos de rutênio (II) em células de Sarcoma 180; Study of potential cytotoxic, genotoxic and cell death mechanism of ruthenium II compounds in sarcoma-180 cells

Pires, Wanessa Carvalho
Fonte: Universidade Federal de Goiás; Brasil; UFG; Programa de Pós-graduação em Ciências Farmacêuticas (FF); Faculdade Farmácia - FF (RG) Publicador: Universidade Federal de Goiás; Brasil; UFG; Programa de Pós-graduação em Ciências Farmacêuticas (FF); Faculdade Farmácia - FF (RG)
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
368.94625%
It is estimated that 27 million new cancer cases will occur in the world until 2030. Due to this high number of cases, researches for new chemotherapeutic agents that are efficient for the malignant neoplastic disease treatment have intensified. Ruthenium complexes have been highlighted from those metal complexes that are being contemplated for the cancer treatment, because they exhibit the characteristics of selectivity for tumor cells and thus be less toxic to normal cells. Consequently, we evaluated the cytotoxic potential of six new complexes of ruthenium (II) and two of those with promising activity were selected to assess the genotoxic potential, the mechanism of death and interference on cell cycle dynamics. The cytotoxicity of these complexes was evaluated by MTT assay showing that for all six ruthenium complexes there was a reduction of viability of the tumor cells K562 and S-180 at low concentrations and cytotoxicity at higher concentrations to normal cells L-929 and lymphocyte. The ruthenium II complexes Ru 05 and Ru 08 got the best resolutions in the MTT assay and were selected for testing genotoxicity and mechanism of death. Data indicate that the Ru 05 and 08 induced changes in cell cycle through test performed by flow cytometry...

Half-sandwich Complexes of Ruthenium; Synthesis and Application to Catalysis

Lee, Sun Hwa
Fonte: Brock University Publicador: Brock University
Tipo: Electronic Thesis or Dissertation
ENG
Relevância na Pesquisa
368.94625%
This thesis describes syntheses and catalytic reactivity of several half-sandwich complexes of ruthenium. The neutral ruthenium trihydride complex, Cp(PPri3)RuH3(1), can efficiently catalyse the H/D exchange reaction between various organic substrates and deuterium sources, such as benzene-d6. Moreover, the H/D exchange reactions of polar substrates were also observed in D2O, which is the most attractive deuterium source due to its low cost and low toxicity. Importantly, the H/D exchange under catalytic conditions was achieved not only in aromatic compounds but also in substituted liphatic compounds. Interestingly, in the case of alkanes and alkyl chains, highly selective deuterium incorporation in the terminal methyl positions was observed. It was discovered that the methylene units are engaged in exchange only if the molecule contains a donating functional group, such as O-and N-donors, C=C double bonds, arenes and CH3. The cationic half-sandwich ruthenium complex [Cp(PPri3)Ru(CH3CN)2]+(2) catalyses the chemoselective mono-addition of HSiMe2Ph to pyridine derivatives to selectively give the 1,4-regiospecific, N-silylated products. An ionic hydrosilylation mechanismis suggested based on the experiments. To support this mechanistic proposal...

Imaging investigations of the ruthenium(III) anti-cancer drugs, NAMI-A and KP1019, and novel analogues.

Antony, Sumy
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2014
Relevância na Pesquisa
375.13082%
The success of platinum-based anti-cancer agents, such as cisplatin, has led to further investigation of the utilisation of other non-platinum metal compounds in cancer therapy. The research has generated particular interest in ruthenium-based chemotherapeutics, as ruthenium species display numerous characteristics which make them appropriate for drug design. Numerous small-molecule ruthenium complexes e.g., NAMI-A (new anti-metastatic inhibitor; ‘A’ stands for first compound in the series; [ImH][trans-RuCl₄(DMSO)(Im)]; Im = imidazole) and KP1019 (Keppler compound 1019; [IndH][trans-RuCl₄Ind₂]; Ind = indazole), have been discovered and found to exhibit promising anticancer properties without complete knowledge about the mechanism of their activity. To develop more targeted drugs with reduced toxicity, it is important to have an accurate knowledge about the mechanism of anti-metastatic activity of these drugs in a complete biological system. Our specific interest in this research has been concerned with the investigation of anti-metastatic activity of analogues of NAMI-A and KP1019 by advanced techniques such as synchrotron-based X-ray fluorescence imaging (XRF) and fluorescent microscopy imaging. A series of ruthenium(III) complexes...

Synthesis of Novel Neutral and Cationic Diamine-bis(ether-phosphine)ruthenium(II) Complexes in Homogeneous and Heterogeneous States as Tools for Parallel Catalyst Screening; Synthese neuartiger neutraler und kationischer Diamin-bis(ether-phosphan)ruthenium(II)-Komplexe in homogener und heterogener Phase als Werkzeug für paralleles Katalysator-Screening

Al-Gharabli, Samer Ibrahim Abed-Rabbo
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
DE_DE
Relevância na Pesquisa
374.78297%
A matrix of neutral diamine–bis(ether–phosphine)ruthenium(II) complexes were synthesized by treatment of the precursor complex RuCl2(h2-Ph2PCH2CH2OCH3)2 with various chelating diamines. The reaction of these complexes with one equivalent of AgSbF6, AgBF4, or TlPF6 led to the abstraction of one chloride by simultaneously coordinating one ether-oxygen atom to ruthenium with formation of the monocationic analogous. If a large excess of silver or thallium salt is used, the dichloro complexes are converted to the dications [Ru(h2-Ph2PCH2CH2OCH3)2(diamine)]2+. To merge parallel synthesis and interphase chemistry, the ether-phosphine ligand Ph2PCH2CH2OCH3 was modified by providing an adequate spacer carrying a triethoxysilyl group (T-silyl) at the periphery of the ligand system. The modified ligand C6H5P(CH2CH2OCH3)C6H4CH2NHC(O)NHCH2CH2CH2Si(OEt)3 was used in the synthesis of a matrix of T–silyl functionalized neutral ruthenium(II) complexes Cl2Ru(P~O)2(diamine) by addition of the same series of aliphatic and aromatic diamines to the bis(chelated) precursor complex Cl2Ru(P~O)2. The corresponding monocationic ruthenium(II) complexes [ClRu(PÇO)(P~O)(diamine)][BF4] were also prepared. The T–silyl functionalized diamine-bis(ether-phosphine)ruthenium(II) complexes were then sol-gel processed in the presence of different amounts of co-condensation agents. The resulting hybrid polymers offer a new array of complexes with variable mobilities...

Diamine(phosphine)ruthenium(II) Complexes and Their Application in The Catalytic Hydrogenation of alpha,beta-Unsaturated Ketones in Homogeneous and Heterogeneous Phase; Diamin(phosphin)ruthenium(II)-Komplexe und ihre Anwendung in der katalytischen Hydrierung von alpha,beta-ungesättigten Ketonen in homogener und heterogener Phase

Warad, Ismail
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
EN
Relevância na Pesquisa
371.2638%
The objective of this thesis was the preparation and characterization of ruthenium(II)- complexes with different types of diamine and phosphine ligands. Such species are active in the selective hydrogenation of alpha,beta-unsaturated ketones under mild conditions in homogeneous and heterogeneous phase. Several diamine(ether-phosphine)ruthenium(II) complexes have been successfully supported onto a polysiloxane matrix by the sol-gel process after modifying the ether-phosphine ligand with T-silyl function. The catalytic activity of the homogeneous and interphase ruthenium(II) catalysts in the selective hydrogenation of alpha,beta-unsaturated ketones as model substrates has been probed. Most of these complexes were highly catalytically active in the hydrogenation of the alpha,beta-unsaturated ketone trans-4-phenyl-3-butene-2-one. Further experiments were devoted to the role of the co-catalysts. In most cases the conversions and selectivities toward the formation of the unsaturated alcohol trans-4-phenyl-3-butene-2-ol were 100% with high turnover frequencies under mild conditions. To improve the enantioselectivity of the secondary alcohol (up to 99% R and S) which has been produced using complexes with achiral diamines, the kinetic resolution of enantiomerically enriched trans-4-phenyl-3-butene-2-ol was performed in a consecutive approach using lipase-catalyzed enantioselective transesterification of the alcohol in toluene.; Ziel dieser Arbeit war die Darstellung und Charakterisierung von Ruthenium(II)-komplexen mit unterschiedlichen Diamin- und Phosphinliganden. Diese Spezies ist sowohl in homogener als auch in heterogener Phase unter milden Bedingungen aktiv bei der selektiven Hydrierung von alpha...

New stationary phases with diaminebis(phosphine)ruthenium(II) complexes for the catalytic hydrogenation of carbonyl compounds; Neue stationäre Phasen mit Diaminobis(phosphin)ruthenium(II)-Komplexen für die katalytische Hydrierung von Carbonylverbindungen

Reginek, Michaela
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
EN
Relevância na Pesquisa
374.38938%
Catalytic hydrogenation of polar double bonds such as C=O is in demand of fine chemical and pharmaceutical chemistry, especially the asymmetric version of this reaction. Among the diaminedichlorobis(phosphine)ruthenium(II) complexes, there exist examples with extraordinary catalytic performance for this type of hydrogenation. Separation of these catalysts from other reactants after hydrogenation still is a time, energy, and chemical consuming process. Moreover, the complexes might be destroyed during this procedure. Therefore it is of great economical interest to combine the advantages of homogeneous and heterogeneous catalysis by applying the concept of “Chemistry in Interphases” for diaminedichlorobis(phosphine)ruthenium(II) complexes. In a first approach a highly crosslinked polyethylene imine resin, a so-called ULTRARESIN was applied as organic polymeric support. A dichlorobis[(methoxyethyldiphenyl)-phosphine]ruthenium(II) and a dichlorobis[1,3-bis(diphenylphosphino)propane]-ruthenium(II) complex fragment were each successfully anchored to this matrix by coordination to diamine spacers of different length. The diamine spacers were covalently linked to the resin via an amide bond. The new interphase catalysts were employed for the catalytic hydrogenation of acetophenone to 1-phenylethanol...

Efeitos sinérgicos em polipiridinas de rutênio binucleares para reação de oxidação de água e eletrocatálise; Synergic effects in dinuclear ruthenium polypyridyl for water oxidation reaction and electrocatalysis

Matias, Tiago Araujo
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 25/06/2015 PT
Relevância na Pesquisa
372.1122%
Complexos polipiridínicos de rutênio mononuclares vem sendo ativamente estudados como catalisadores da reação de oxidação de água a oxigênio, mas o complexo ativado dos catalisadores mais eficientes envolve a formação de um dímero, indicando a importância da estrutura binuclear para ativação dos mesmos. Assim, nesta tese propomos o estudo dos possíveis efeitos sinérgicos em complexos binucleares de rutênio polipiridinas angulares para ativação das espécies de alta valência do tipo RuV=O e RuIV=O. Assim, foram preparadas séries de complexos polipiridínicos de rutênio empregando os ligantes tridentados derivados de terpiridinas e bidentados tipo bipiridina na forma cloro complexos e aqua complexos mono e binucleares, capazes de atuar como precursores das espécies ativas de alta valência por meio de reações de transferência de elétrons acoplado a transferência de prótons (PCET). Os complexos [RuCl(bpy)(phtpy)](PF6), [Ru2Cl2(bpy)2(tpy2ph)](PF6)2 e [Ru2Cl2(Clphen)2(tpy2ph)](PF6)2 (phtpy= 4'-fenil-2,2':6',2''-terpiridina, bpy= 2,2´-bipiriridina, Clphen= 5-cloro-1,10-fenantrolina e tpy2ph= 1,3-bis(4'-2,2':6',2''-terpiridil)benzeno) e seus aqua complexos foram sintetizados e caracterizados por técnicas espectroscópicas e eletroquímicas. Os complexos [RuCl(bpy)phtpy](PF6)...

Protein binding by dinuclear polypyridyl ruthenium(ii) complexes and the effect of cucurbit[10]uril encapsulation

Li, F.; Feterl, M.; Warner, J.; Day, A.; Keene, F.; Collins, J.
Fonte: Royal Soc Chemistry Publicador: Royal Soc Chemistry
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
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The effect of human serum on the minimum inhibitory/bactericidal concentrations of the potential antimicrobial agents ΔΔ-[{Ru(phen)₂}₂(μ-bb(n))]⁴⁺ {ΔΔ-Rubb(n); where phen = 1,10-phenanthroline, bb(n) = 1,n-bis[4(4′-methyl-2,2′-bipyridyl)]-alkane for n = 12 and 16} against four strains of bacteria – Gram positive Staphylococcus aureus and methicillin-resistant S. aureus (MRSA), and Gram negative Escherichia coli and Pseudomonas aeruginosa – has been determined. The results demonstrated that the ruthenium(II) complexes have significantly decreased in vitro activity in serum. Fluorescence spectroscopy was used to confirm that the decrease in antimicrobial activity was due to the strong binding of the ruthenium complexes with the serum proteins human serum albumin (HSA) and transferrin. A series of ruthenium complexes showed stronger binding to HSA than apo-transferrin but comparable or less than with holo-transferrin, with the binding affinity to all three proteins decreasing in the order trinuclear > dinuclear > mononuclear. The dinuclear complex ΔΔ-Rubb₁₂ displaced warfarin from HSA, tentatively suggesting that the ruthenium complexes bind at or near the warfarin-binding site, Sudlow's site 1. The binding of ΔΔ-Rubb₁₂ and ΔΔ-Rubb₁₆ to the macrocyclic host molecule cucurbit[10]uril (Q[10]) was examined by NMR spectroscopy. The large upfield ¹H NMR chemical shift changes observed for the methylene protons in the bridging ligands upon addition of Q[10]...

Photophysicochemistry of porphyrins and ruthenium complexes adsorbed on mesoporous TiO2 thin films

Sampaio, Renato Neiva
Fonte: Universidade Federal de Uberlândia Publicador: Universidade Federal de Uberlândia
Tipo: Tese de Doutorado
POR
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Durante muitos anos, a busca por novos compostos, orgânicos, organometálicos e inorgânicos tem atraído considerável interesse no meio científico devido às suas potenciais aplicações na tecnologia, medicina e no desenvolvimento de ciência básica e aplicada. Dentre estes novos materiais, se destacam as porfirinas e complexos de rutênio por sua versátil manipulação estrutural via engenharia molecular e suas propriedades foto-físicas e fotoquímicas. Para que viabilize a estimativa de perspectivas dessa classe de compostos para potenciais aplicações, torna-se imperativo desenvolver caracterizações sistemáticas de suas propriedades moleculares, principalmente aquelas envolvendo a formação de seus estados excitados a as possíveis interações com as entidades presentes no meio. Um tópico vigente de intenso interesse de pesquisa científica nos últimos dez anos é a aplicação de moléculas altamente absorvedoras de luz visível, tais como porfirinas e complexos de rutênio, como corantes sensibilizadores em células solares sensibilizadas por corantes (CSSCs). As CSSCs representam um atrativa tecnologia para suprir a demanda mundial por energia renovável. Tais dispositivos são compostos por filmes finos mesoporosos de óxidos metálicos esféricos de escala nanométrica...

Electrochemical studies of Fe-21Cr-1Ni duplex stainless steels with 0.15 wt% ruthenium at different temperatures

Olaseinde,O.A.; van der Merwe,J.W.; Cornish,L.A.; Chown,L.H.; Olubambi,P.A.
Fonte: Journal of the Southern African Institute of Mining and Metallurgy Publicador: Journal of the Southern African Institute of Mining and Metallurgy
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2012 EN
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The 2101 lean duplex stainless steel has wide potential application in storage, heat exchangers, and in the oil and gas industries. This work investigates the electrochemical behaviour of 2101 duplex stainless steel with an addition of 0.15 wt% ruthenium, using potentiodynamic techniques in 1M H2SO4 at 25°, 40°, 60°, and 80°C. The microstructures of samples were characterized using optical metallography and scanning electron microscopy. The results showed that the ruthenium addition moved the corrosion potential of alloy 2101 to a more positive potential. All samples containing ruthenium displayed longer passive regions at 25°C and 80°C compared to those without ruthenium. Alloys without ruthenium had higher critical current density (?'crit) values when compared to the alloys with ruthenium. Ruthenium additions decreased the passive current densities and inhibited anodic dissolution. At room temperature the corrosion rate of alloys with ruthenium was lower than these without ruthenium.