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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Estrutura e reatividade de complexos organometálicos de Au(III)

Delgado, Giset Yuliana Sanchez 11 August 2017 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-11-07T10:28:17Z No. of bitstreams: 1 gisetyulianasanchezdelgado.pdf: 4087455 bytes, checksum: 74e12bffed9f492497ef465546d6ac98 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-11-09T14:36:17Z (GMT) No. of bitstreams: 1 gisetyulianasanchezdelgado.pdf: 4087455 bytes, checksum: 74e12bffed9f492497ef465546d6ac98 (MD5) / Made available in DSpace on 2017-11-09T14:36:17Z (GMT). No. of bitstreams: 1 gisetyulianasanchezdelgado.pdf: 4087455 bytes, checksum: 74e12bffed9f492497ef465546d6ac98 (MD5) Previous issue date: 2017-08-11 / Na última década, os complexos de Au(III) tornaram-se uma classe importante de compostos com promissores efeitos anticancerígenos. Geralmente, em condições fisiológicas, os complexos de Au(III) são bastante reativos devido à alta afinidade dos íons de ouro em relação aos nucleófilos celulares e devido à instabilidade através das reações redox intracelulares. Métodos da teoria do funcional da densidade (DFT) foram aplicados no presente trabalho para calcular o potencial de redução padrão de nove complexos organometálicos de Au(III) do tipo [Au3+(R-C^N^C)L]n, usando dados experimentais disponíveis como referência. Em geral, os métodos DFT levaram a resultados satisfatórios com um erro médio absoluto inferior a 170 mV. O funcional CAM-B3LYP em combinação com o modelo de solvatação SMD, foi superior aos resultados de wB97xD, M11-L e B3LYP, com um erro médio absoluto de 81 mV em relação ao par redox ferroceno/ferrocênio (Fc+/Fc). No entanto, apesar do maior erro encontrado para os resultados B3LYP, a tendência qualitativa encontrada na série de moléculas estudadas foi a mais próxima daquela observada experimentalmente, o que permitiu propor um modelo de escalonamento usando o potencial de redução experimental como variável dependente e a energia livre de Gibbs calculada como variável independente. A regressão linear foi estatisticamente aceitável (R2=0,8) no nível B3LYP levando a um erro de apenas 35 mV. Além disso, a metodologia “the variable-temperature H-atom addition/abstraction (VT-HAA)” foi aplicada para os pares redox com cargas não equivalentes (complexos contendo cloreto como ligante), levando a uma melhora significativa na previsão do potencial de redução. O erro médio absoluto foi de apenas 87 mV, inferior ao encontrado com o protocolo padrão (144 mV). Na sequencia, a reatividade dos complexos de Au(III) foi estudada abordando dois diferentes caminhos para a redução do complexo [Au3+(C^N^C)Cl], os quais incluem reações de troca de ligantes associadas a processos de redução na presença de bionucleófilos de interesse (H2O, CH3SH CH3SeH e meim-4). Os resultados DFT mostraram que o caminho de reação mais favorável passa em primeiro lugar através da troca do cloreto ( =2,59 M-1 s-1 para CH3SeH) e, em seguida, o metabólito de Au(III) é reduzido ao análogo correspondente de Au(I) implicando na abertura do quelato (ɛ˚=+0,33 V para o derivado de CH3SeH). / In the last decade, Au(III) complexes become an important class of compounds with promising anticancer effects. Generally, under physiological conditions the Au(III) complexes are quite reactive due to the high affinity of gold ions toward cellular nucleophiles, and due to the instability through the intracellular redox reactions. Density functional theory (DFT) methods were herein applied to calculate the standard reduction potential of nine Au(III) organometallic complexes of the type [Au3+(R-C^N^C)L]n, using available experimental data as benchmark. Overall, the DFT methods lead to satisfactory results, with absolute error lower than 170 mV. The CAM-B3LYP functional in combination with the SMD solvation model was superior to wB97xD, M11-L and B3LYP results, with absolute error of 81 mV relative to ferrocene/ferrocenium (Fc+/Fc) redox couple. However, in spite of the larger error found for B3LYP results, the qualitative trend was closer to the observed one, which allowed the proposal of a scaling model using the experimental reduction potential as dependent variable and the calculated reaction Gibbs free energy as independent variable. The linear regression was statistically acceptable (R2=0.8) at B3LYP level and lead to an average error of only 35 mV. Besides, the variable-temperature H-atom addition/abstraction (VT-HAA) approach was applied for the redox couples with non-equivalent charges (complexes containing chloride as ligand), leading to a significant improvement in the reduction potential prediction. The mean absolute error was only 87 mV without any scaling procedure, which is much lower than found for standard approach, 144 mV. Moreover, the reactivity of Au(III) complexes was studied including two different pathways to the reduction of the [Au3+(C^N^C)Cl] complex, which involve ligand exchange reactions associated with reduction processes in the presence of bionucleophiles of interest (H2O, CH3SH CH3SeH e meim-4). The DFT results show that the most favorable reaction path passes firstly through chloride-exchange ( =2.59 M-1 s-1 for CH3SeH) and then the Au(III) metabolite is promptly reduced to the corresponding Au(I) analogue with ring-opening (ɛ˚=+0.33 V for CH3SeH derivative).
12

Compostos de coordenação de Ir(III), Re(I) e Ru(II) para aplicações em dispositivos moleculares / Ir(III), Re(I) and Ru(II) coordination compounds towards application in molecular devices

Zanoni, Kassio Papi da Silva 01 April 2016 (has links)
Esta tese focou em três tópicos principais: caracterização de filmes compactos de TiO2 e seu comportamento em células solares sensibilizadas por corante; estudo das propriedades fotoquímicas e fotofísicas de um complexo fotoisomerizável de rênio(I); elucidação das propriedades fotofísicas e eletrônicas de complexos de irídio(III) e suas aplicações em dispositivos emissores de luz. Filmes compactos foram automontados nos fotoanodos de células solares sensibilizadas por corante (DSCs), sob o filme mesoporoso de TiO2/corante, utilizando sols de TiO2 ácidos e básicos como cátions e ânions, respectivamente. A obtenção dos sols foi realizada sob controle absoluto para resultar em propriedades morfológicas e ópticas apropriadas para filmes compactos de alta qualidade, como indicado por perfilometria e microscopia eletrônica de transmissão e varredura. As DSCs com bicamadas de TiO2 melhoraram as eficiências de conversão em até 62%. Uma investigação detalhada por parâmetros fotoeletroquímicos, IPCE, tempo de vida do elétron e espectroscopia de impedância eletroquímica demonstrou que o contato entre o vidro condutor (FTO) e o TiO2 é melhorado e que a recombinação de carga no FTO/I3- é diminuída. O novo complexo fac-[Re(CO)3(Ph2phen)(trans-stpyCN)]+ foi sintetizado para apresentar o intercâmbio entre as configurações trans e cis do ligante coordenado por meio de fotoisomerizações eficientes e reversíveis. As fotólises em 313, 334, 365 e404 nm resultam em mudanças espectrais no UV-Vis e RMN atribuídas à fotoisomerização trans-cis do ligante stpyCN coordenado. O processo reverso cis-trans também foi observado com irradiação em 255 nm, com um notável rendimento quântico (&#934 = 0,16), de mesma magnitude que para o processo trans-cis (Φ = 0,38). A caracterização fotofísica e os espectros de absorção do transiente corroboraram na atribuição de um comportamento incomum para os estados excitados quasedegenerados 3ILstpyCN e 3MLCTRe→Ph2phen. Complexos heterolépticos de Ir(III) foram sintetizados e suas propriedades fotofísicas avaliadas, como rendimentos quânticos e tempos de vida de emissão, constantes radiativas e não-radiativas e coordenadas CIE. Os parâmetros fotofísicos variaram sistematicamente com variações nos substituintes retiradores ou doares de elétrons, como corroborado por cálculos TD-DFT, que mostraram uma mistura de estados excitados IL-MLCT. Três desses complexos foram utilizados na camada ativa de dispositivos emissores de luz e caracterizados optoeletronicamente por curvas de corrente-brilho-potencial e espectros eletroluminescentes. / Three main topics are discussed in this thesis: characterization of TiO2 compact films towards high-performance dye-sensitized solar cells; investigations of photophysical and photochemical processes of a Re(I) complex; photophysical elucidation of Ir(III) complexes and their application in light emitting devices. All-nano-TiO2 compact films were auto-assembled in the photoanodes of dyesensitized solar cells (DSCs), beneath the TiO2 mesoporous film, employing acid and basic nano-TiO2 sols as cations and anions, respectively. TiO2 syntheses were performed under absolute control to lead to appropriate morphological and optical properties to yield high quality compact films, as indicated by profilometry, tunning and scanning electron microscopy. DSCs with TiO2 bilayers on top of the conducting glass (FTO) improved the conversion efficiency up to 62%. A detailed study by photoelectrochemical parameters, IPCE, electron lifetime and electrochemical impedance spectroscopy demonstrates that the contact between FTO and TiO2 was improved and that the FTO/I3- charge recombination was prevented. The novel fac-[Re(CO)3(Ph2phen)(trans-stpyCN)]+ complex was synthesized to show switchable trans-cis configurations of the coordinated stpyCN ligand through efficient and reversible photoassisted isomerizations. Photolyses at 313, 334, 365 and 404 nm led to UV-Vis and NMR spectral changes ascribed to the trans-to-cis photoisomerization of the coordinated ligand. The reverse cis-to-trans process was alsoobserved at 255 nm irradiation, with a remarkable quantum yield (Φ = 0.16), in the same magnitude to the one for trans-to-cis photoprocess (Φ = 0.38). Photophysical characterization and transient absorption spectra provided insights on the light-driven trans ? cis pathways and indicated an unusual behavior for the 3ILstpyCN excited state, induced by an interplay with the quasi-degenerated 3MLCTRePh2phen state. Heteroleptic Ir(III) complexes were synthesized and phophysical properties evaluated, such as emission quantum yields and lifetimes, radiative and non-radiative constants and CIE coordinates. The photophysical parameters varied systematically with variations in electron-donating or -withdrawing substituents on the ligands, as corroborated by TD-DFT calculations that showed an IL-MLCT mixing in their emissive excited state. Three complexes were employed in the active layer of light emitting devices and had their optoeletronic properties characterized by current-brightness-voltage curves and electroluminescent spectra.
13

Dispositivos moleculares para conversão de energia: filmes compactos de TiO2 em DSPECs e complexos de Ir(III) / Molecular devices for energy conversion: TiO2 compact films in DSPECs and Ir(III) complexes

Coppo, Rodolfo Lopes 13 December 2018 (has links)
Nessa tese, duas frentes de trabalho foram abordadas: a aplicação de camadas compactas de TiO2 nanoestruturado em células fotoeletrossintéticas sensibilizadas por corante (DSPECs) e a síntese e caracterização de uma série de complexos polipiridínicos de Ir(III), visando à aplicação em dispositivos moleculares. A primeira investigação focou na obtenção de sóis de TiO2 nanoestruturado utilizando um método sol-gel. As deposições dessas nanopartículas pelo método Layer-by-Layer levaram ao crescimento de filmes finos, que foram aplicados no fotoanodo das DSPECs, entre o substrato condutor e o óxido mesoporoso, com o objetivo de avaliar o desempenho desses dispositivos. Os filmes obtidos são altamente compactos e a caracterização fotoeletroquímica das DSPECs apontou que eles propiciaram o aumento da fotocorrente em até 53%, em comparação aos dispositivos não modificados. A voltametria mostrou que as camadas compactas atuam também no deslocamento a potenciais mais negativos, o que pode levar a um aumento na eficiência da geração de oxigênio. As eficiências de conversão de fótons incidentes em corrente (IPCE) corroboraram o papel dessas camadas nos fotoanodos dos dispositivos. As medidas de decaimento de potencial/tempo de vida do elétron no eletrodo − realizados pioneiramente em DSPECs − demonstraram o sucesso na implementação dessa proposta inovadora. A segunda parte deste trabalho focou na obtenção de complexos de Ir(III) com potenciais aplicações em sistemas luminescentes. Três novos complexos polipiridínicos heterolépticos de Ir(III) [Ir(Fppy)2(CF3pic)], [Ir(ppy)2(CF3pic)] e [Ir(Meppy)2(CF3pic)], em que Fppy = 2-(2,4-difluorofenil)piridina, ppy = 2-fenilpiridina, Meppy = 2-(p-toluil)piridina e CF3pic = 3-(trifluorometil)piridina-2-carboxilato, foram obtidos para avaliar suas propriedades fotofísicas em diferentes meios. Dentre os compostos investigados, o [Ir(Fppy)2(CF3pic)] apresentou um perfil bastante diferenciado. Seu estado excitado em meio fluido, acetonitrila, é característico de 3MLCT (transferência de carga metal-ligante) com 13% de rendimento quântico de emissão. Em meio de rigidez intermediária, poli(metil metacrilato) (PMMA), observase uma inversão do estado excitado de mais baixa energia, com um decaimento radiativo típico de 3IL (transição eletrônica intra-ligante), ao passo que para os demais complexos investigados, a emissão em PMMA ainda é do tipo 3MLCT. Em meio vítreo, altamente rígido, a emissão de todos os compostos apresenta bandas características de 3IL, bastante estruturadas e deslocadas para o azul. O efeito rigidocrômico foi discutido e sumarizado em termos de diagramas de energia. Diagramas de cromaticidade também foram obtidos, mostrando as coordenadas CIE (Comission Internationale dEclairage) referentes às cores de emissão de cada complexo. Esse trabalho apresenta a importância da fotofísica desses compostos para potenciais aplicações em dispositivos moleculares. / The main focus of this thesis is: application of nanostructured TiO2 compact layers in dye-sensitized photoelectrosynthesis cells (DSPECs) and syntheses and characterization of Ir(III) polypyridyl complexes towards molecular devices. The first investigation focused on the preparation of nanostructured TiO2 sols using a sol-gel method. The deposition of these nanoparticles through the Layer-by-Layer method led to a thin film growth, which were applied at the photoanode of DSPECs between the conducting glass and the mesoporous network to evaluate the performance of these devices. The obtained thin films are highly compact and the photoelectrochemical characterization of DSPECs showed photocurrent enhancements of 53%, compared with non-modified devices. Voltammetry analyses depicted that the compact layers promote shifts to more negative potentials, which may lead to higher oxygen evolution efficiencies. Incident photon-to-current efficiencies (IPCE) corroborate the role of compact layers in these devices. Potential decay/electron lifetime measurements − pioneered in DSPECs − demonstrated a successful accomplishment of such an innovative approach. The second part of this work focused on the obtention of Ir(III) complexes with potential application in luminescent systems. Three new polypyridyl heteroleptic Ir(III) complexes [Ir(Fppy)2(CF3pic)], [Ir(ppy)2(CF3pic)] and [Ir(Meppy)2(CF3pic)], where Fppy = 2-(2,4-difluorophenyl)pyridine, ppy = 2-phenylpyridine, Meppy = 2-(p-tolyl)pyridine and CF3pic = 3-(trifluoromethyl)pyridine-2-carboxylate, were obtained to evaluate their photophysical properties in different media. Among the investigated complexes, [Ir(Fppy)2(CF3pic)] showed a distinct profile and its excited state in fluid medium, acetonitrile, is typically 3MLCT (metal-to-ligand charge transfer) in character with an emission quantum yield of 13%. In an intermediate-rigidity medium, as poly(methyl metacrilate) (PMMA), an inversion of the lowest-lying state is observed, with a 3IL (intra-ligand) character emission, whereas for other complexes in PMMA remain 3MLCT. In glassy medium, highly rigid, all compounds depict characteristic 3IL bands, well structured and blue-shifted. This rigidochromic effect was rationalized through energy diagrams. Chromaticity diagrams were also obtained and show theCIE (Comission Internationale dEclairage) coordinates for the emitted color of each complex. This work features an appealing study of complex photophysics, where potential application of these compounds are pointed out.
14

Cycloisomérisations catalysées par les sels du gallium et les complexes NHC-Gallium(III) / Cycloisomerizations Catalyzed by Gallium Salts and NHC-Gallium(III) Complexes

Tang, Shun 15 November 2013 (has links)
Afin de développer des méthodes alternatives à l'activation de systèmes Pi en catalyse homogène par des métaux nobles coûteux et toxiques, nous nous sommes focalisés sur des complexes métalliques et plus particulièrement ceux de la colonne du group XIII. Cette thèse approche une contribution à ce champ d'études, et nous nous sommes particulièrement concentrés sur la chimie de gallium.Trois principaux aspects ont été étudiés dans ce manuscrit: la réactivité des halogénures de gallium(III), des complexes bien définis de gallium (III) portant carbènes N- hétérocycliques (NHCs), et leur activation de systèmes en catalyse.La thèse est divisée en trois chapitres. Le premier chapitre donne un aperçu des travaux effectués dans le domaine de la synthèse organique faisant intervenir des composés de gallium (III) , en se concentrant sur ​​leur utilisation en tant qu’ acides de Lewis et .Dans le deuxième chapitre, nous avons tenté d'exploiter le potentiel catalytique de GaCl3 dans une nouvelle réaction de cycloisomérisation/Friedel-Crafts en tandem. Une section dédiée à l'étude sur l’hydratation d’alcyne catalysée par GaCl3 est également fournie.Le troisième chapitre commence par une description de la synthèse d'une série de complexes de gallium (III) portant diverses NHCs comme ligands pour surmonter les limites des halogénures de gallium(III) en catalyse. Ensuite, des études de méthodologie sur le processus de tandem impliquant arenynes-1,6 avec les gallium(III) complexes neutres et cationiques ont été décrits. Une évaluation cinétique pour des catalyseurs, des divers substrats et l'influence de contreanions sont discutés. En outre, les efforts dans la version asymétrique de cette tandem transformation et des autres cyclisations sont également présentés.Le dernier chapitre reprend les résultats les plus importants obtenus dans la thèse. Et les orientations futures de la recherche sur l'utilisation des complexes NHC- gallium (III) sont discutées. / Recently, in order to develop alternative activation methods for Pi-systems in homogeneous catalysis instead of employing expensive and toxic noble metal catalysts, first row transition metals and main group metal complexes have attracted great attention. This thesis is a contribution to it, and we focus on gallium chemistry. There are three main aspects dominating this thesis: gallium(III) halides, well-defined gallium(III) complexes bearing N-heterocyclic carbenes (NHCs), and -systems activation in catalysis.The thesis is divided into three chapters. Chapter I provides an overview of the field of organic synthesis involving gallium(III) compounds, focusing on their use as - or -Lewis acids.In Chapter II, we expose our attempts to exploit the catalytic potential of gallium(III) chloride in a novel tandem cycloisomerization/Friedel-Crafts reaction. A section dedicated to the study on GaCl3-catalyzed alkyne hydration is also provided.Chapter III begins with a description of the synthesis of a series of gallium(III) complexes bearing various NHCs as ligands in order to overcome the limitations of gallium(III) halides in catalysis. Next, methodology studies on the tandem process involving 1,6-arenynes with the neutral and cationic gallium(III) complexes are described. The evaluation of scission kinetics for catalysts, substrates variation and influence of counteranions are discussed. In addition, efforts towards the asymmetric version of this tandem transformation and some other cyclizations are also presented.The concluding chapter reiterates the most important results obtained in the body chapters of the thesis. To conclude, the future directions for the research on the use of the NHC-gallium(III) complexes are discussed.
15

Síntese, caracterização e estudo da ação antituberculose e citotóxica de hidrazonas derivadas de isoniazida e de seus complexos de cobre(II) e gálio(III) / Synthesis, characterization and study of antituberculosis and cytotoxic action of isoniazid-derived hydrazones and its copper(II) and gallium(III) complexes

Gisele dos Santos Silva Firmino 30 January 2015 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / No presente trabalho é descrita a obtenção de hidrazonas derivadas de isoniazida e de seus complexos de cobre(II) e gálio(III) candidatos a protótipos de fármacos antituberculose e antitumoral. Para investigar o efeito da modificação química sobre as bioatividades do fármaco isoniazida, foram preparados cinco derivados hidrazônicos: 2-piridinocarboxaldeído isonicotinoil hidrazona (HPCIH, 1), 2-acetilpiridina isonicotinoil hidrazona (HAPIH, 2), 2-benzoilpiridina isonicotinoil hidrazona (HBPIH, 3), 2-piridinoformamida isonicotinoil hidrazona (HPAmIH, 4) e 2-pirazinoformamida isonicotinoil hidrazona (HPzAmIH, 5), sendo o composto HPAmIH (4) inédito. Análises de ponto de fusão, espectroscopia de infravermelho (IV), espectrometria de massas, ressonância magnética nuclear (RMN), análise elementar e termogravimetria confirmaram a obtenção e pureza das hidrazonas. Foi determinada ainda a estrutura de HPCIH (1) por difração de raios X de monocristal. Essas moléculas foram efetivas em inibir o crescimento de cepas de micobactérias Mycobacterium tuberculosis H37Rv (ATCC 27294) nas concentrações testadas, com exceção de HPzAmIH (5). As hidrazonas HAPIH (2) e HBPIH (3) foram os compostos orgânicos mais ativos (concentração inibitória mínima, CIM = 0,625 g/mL), apresentando atividade antimicobacteriana apenas duas vezes inferior à do fármaco isoniazida.Quanto à ação contra células tumorais, as hidrazonas HAPIH (2) e HBPIH (3) foram as mais potentes contra as linhagens OVCAR-8 (tumor de ovário - humano), HCT-116 (tumor de cólon - humano) e SF-295 (glioblastoma humano), com inibições de 34,98 a 98,63% do crescimento celular, na concentração de 5 g/mL, enquanto que a isoniazida não foi efetiva contra as linhagens estudadas. Para avaliar o efeito da coordenação a metais sobre a atividade farmacológica das hidrazonas, foram sintetizados os complexos de cobre(II) e gálio(III), sendo todos inéditos: [Cu(HPCIH)Cl2]∙H2O (6), [Cu(HAPIH)Cl2]∙H2O (7), [Cu2(HBPIH)2Cl2]Cl2∙4H2O(8), [Cu(HPAmIH)Cl2]∙H2O (9), [Cu(HPzAmIH)Cl2]∙H2O (10), [Ga(HPCIH)2](NO3)32H2O (11), [Ga(HAPIH)(APIH)](NO3)22H2O (12), [Ga(HPAmIH)(PAmIH)](NO3)22H2O(13) e [Ga(HPzAmIH)(PzAmIH)](NO3)2H2O (14). Os complexos foram caracterizados por espectroscopia de IV, análise elementar, condutivimetria, RMN e espectroscopia eletrônica. Em geral, os complexos também demonstraram ação contra M. tuberculosis, sendo que apenas para 6, 9, 10 e 14 foi verificada melhor atividade em relação às hidrazonas livres. Os complexos metálicos foram tanto quanto ou mais ativos contra as células tumorais OVCAR-8, HCT-116 e SF-295 do que as hidrazonas livres. Merecem destaque os complexos 79 e 12, que apresentaram inibição de crescimento celular de 72,2100%, na concentração de 5 g/mL. Os resultados demonstram portanto que em geral os compostos 114 são menos ativos do que a isoniazida contra M. tuberculosis, enquanto que a modificação química do fármaco, formando-se hidrazonas com posterior complexação cobre(II) e gálio(III) constituíram uma estratégia interessante na obtenção de compostos mais potentes contra células tumorais / In this work we describe the synthesis of isoniazide-derived hydrazones and their copper(II) and gallium(III) complexes candidates for drug prototypes to treat antituberculosis and cancer. Five hidrazone derivatives have been prepared in order to investigate the effect of chemical modification on the bioactivities of the drug isoniazid: 2-pyridinecarboxaldehyde isonicotinoyl hydrazone (HPCIH, 1), 2-acetylpyridine isonicotinoyl hydrazone (HAPIH, 2), 2-benzoylpyridine isonicotinoyl hydrazone (HBPIH, 3), 2-pyridineformamide isonicotinoyl hydrazone (HPAmIH, 4) and pyrazineformamide 2-isonicotinoyl hydrazone (HPzAmIH, 5), being HPAmIH (4) unpublished. Melting point, infrared spectroscopy (IR), mass spectrometry, nuclear magnetic resonance (NMR), elemental analysis and thermogravimetric analysis has confirmed the formation of hydrazones as well as its purity. All compounds have been effective in inhibiting the growth of Mycobacterium tuberculosis H37Rv (ATCC 27294) mycobacteria strains in the tested concentrations, except HPzAmIH (5). The hydrazones HAPIH (2) and HBPIH (3) have been the most active compounds (minimum inhibitory concentration, MIC = 0.625 g/mL), which have presented the antimycobacterial activity only two times lower than isoniazid drug. In relation to the action against tumor cells, the hydrazones HAPIH (2) and HBPIH (3) have been the most potent compounds against the cell lines OVCAR-8 (ovarian tumor - human), HCT-116 (colon tumor - human) and SF-295 (glioblastoma - human), with inhibitions from 34.98 to 98.63% of cellular growth at a concentration of 5 g/mL. Isoniazid, in turn, hasnt been effective against all cell lines studied. To evaluate the effect of coordinating the metal on the pharmacological activity of hydrazones, complexes of copper (II) and gallium (III) have been synthesized, being all novel compounds: [Cu(HPCIH)Cl2]∙H2O (6), [Cu(HAPIH)Cl2]∙H2O (7), [Cu2(HBPIH)2Cl2]Cl2∙4H2O(8), [Cu(HPAmIH)Cl2]∙H2O (9), [Cu(HPzAmIH)Cl2]∙H2O (10), [Ga(HPCIH)2](NO3)32H2O (11), [Ga(HAPIH)(APIH)](NO3)22H2O (12), [Ga(HPAmIH)(PAmIH)](NO3)22H2O (13) and [Ga(HPzAmIH)(PzAmIH)](NO3)2H2O (14).The complexes have been characterized by IR spectroscopy, NMR, elemental analysis, conductivimetry and electron spectroscopy. In general, these complexes have also shown action against M. tuberculosis, whereas only 6, 9, 10 and 14 have demonstrated better activity than the free hydrazones. The metal complexes have been equally or more active against human the cancer cell lines OVCAR-8, HCT-116 and SF-295 than the free hydrazones. The complexes 79 and 12 deserve to be highlighted, which have shown 72.2100% inhibition of cell growth in the 5 g/mL concentration. The results therefore demonstrate that in general compounds 114 are less active than isoniazid against M. tuberculosis, while chemical modification of the drug, forming hydrazones and subsequent complexation with the copper (II) and gallium(III) metal ions have been an interesting strategy to obtain compounds more potent against tumor cells
16

Síntese, caracterização e estudo da ação antituberculose e citotóxica de hidrazonas derivadas de isoniazida e de seus complexos de cobre(II) e gálio(III) / Synthesis, characterization and study of antituberculosis and cytotoxic action of isoniazid-derived hydrazones and its copper(II) and gallium(III) complexes

Gisele dos Santos Silva Firmino 30 January 2015 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / No presente trabalho é descrita a obtenção de hidrazonas derivadas de isoniazida e de seus complexos de cobre(II) e gálio(III) candidatos a protótipos de fármacos antituberculose e antitumoral. Para investigar o efeito da modificação química sobre as bioatividades do fármaco isoniazida, foram preparados cinco derivados hidrazônicos: 2-piridinocarboxaldeído isonicotinoil hidrazona (HPCIH, 1), 2-acetilpiridina isonicotinoil hidrazona (HAPIH, 2), 2-benzoilpiridina isonicotinoil hidrazona (HBPIH, 3), 2-piridinoformamida isonicotinoil hidrazona (HPAmIH, 4) e 2-pirazinoformamida isonicotinoil hidrazona (HPzAmIH, 5), sendo o composto HPAmIH (4) inédito. Análises de ponto de fusão, espectroscopia de infravermelho (IV), espectrometria de massas, ressonância magnética nuclear (RMN), análise elementar e termogravimetria confirmaram a obtenção e pureza das hidrazonas. Foi determinada ainda a estrutura de HPCIH (1) por difração de raios X de monocristal. Essas moléculas foram efetivas em inibir o crescimento de cepas de micobactérias Mycobacterium tuberculosis H37Rv (ATCC 27294) nas concentrações testadas, com exceção de HPzAmIH (5). As hidrazonas HAPIH (2) e HBPIH (3) foram os compostos orgânicos mais ativos (concentração inibitória mínima, CIM = 0,625 g/mL), apresentando atividade antimicobacteriana apenas duas vezes inferior à do fármaco isoniazida.Quanto à ação contra células tumorais, as hidrazonas HAPIH (2) e HBPIH (3) foram as mais potentes contra as linhagens OVCAR-8 (tumor de ovário - humano), HCT-116 (tumor de cólon - humano) e SF-295 (glioblastoma humano), com inibições de 34,98 a 98,63% do crescimento celular, na concentração de 5 g/mL, enquanto que a isoniazida não foi efetiva contra as linhagens estudadas. Para avaliar o efeito da coordenação a metais sobre a atividade farmacológica das hidrazonas, foram sintetizados os complexos de cobre(II) e gálio(III), sendo todos inéditos: [Cu(HPCIH)Cl2]∙H2O (6), [Cu(HAPIH)Cl2]∙H2O (7), [Cu2(HBPIH)2Cl2]Cl2∙4H2O(8), [Cu(HPAmIH)Cl2]∙H2O (9), [Cu(HPzAmIH)Cl2]∙H2O (10), [Ga(HPCIH)2](NO3)32H2O (11), [Ga(HAPIH)(APIH)](NO3)22H2O (12), [Ga(HPAmIH)(PAmIH)](NO3)22H2O(13) e [Ga(HPzAmIH)(PzAmIH)](NO3)2H2O (14). Os complexos foram caracterizados por espectroscopia de IV, análise elementar, condutivimetria, RMN e espectroscopia eletrônica. Em geral, os complexos também demonstraram ação contra M. tuberculosis, sendo que apenas para 6, 9, 10 e 14 foi verificada melhor atividade em relação às hidrazonas livres. Os complexos metálicos foram tanto quanto ou mais ativos contra as células tumorais OVCAR-8, HCT-116 e SF-295 do que as hidrazonas livres. Merecem destaque os complexos 79 e 12, que apresentaram inibição de crescimento celular de 72,2100%, na concentração de 5 g/mL. Os resultados demonstram portanto que em geral os compostos 114 são menos ativos do que a isoniazida contra M. tuberculosis, enquanto que a modificação química do fármaco, formando-se hidrazonas com posterior complexação cobre(II) e gálio(III) constituíram uma estratégia interessante na obtenção de compostos mais potentes contra células tumorais / In this work we describe the synthesis of isoniazide-derived hydrazones and their copper(II) and gallium(III) complexes candidates for drug prototypes to treat antituberculosis and cancer. Five hidrazone derivatives have been prepared in order to investigate the effect of chemical modification on the bioactivities of the drug isoniazid: 2-pyridinecarboxaldehyde isonicotinoyl hydrazone (HPCIH, 1), 2-acetylpyridine isonicotinoyl hydrazone (HAPIH, 2), 2-benzoylpyridine isonicotinoyl hydrazone (HBPIH, 3), 2-pyridineformamide isonicotinoyl hydrazone (HPAmIH, 4) and pyrazineformamide 2-isonicotinoyl hydrazone (HPzAmIH, 5), being HPAmIH (4) unpublished. Melting point, infrared spectroscopy (IR), mass spectrometry, nuclear magnetic resonance (NMR), elemental analysis and thermogravimetric analysis has confirmed the formation of hydrazones as well as its purity. All compounds have been effective in inhibiting the growth of Mycobacterium tuberculosis H37Rv (ATCC 27294) mycobacteria strains in the tested concentrations, except HPzAmIH (5). The hydrazones HAPIH (2) and HBPIH (3) have been the most active compounds (minimum inhibitory concentration, MIC = 0.625 g/mL), which have presented the antimycobacterial activity only two times lower than isoniazid drug. In relation to the action against tumor cells, the hydrazones HAPIH (2) and HBPIH (3) have been the most potent compounds against the cell lines OVCAR-8 (ovarian tumor - human), HCT-116 (colon tumor - human) and SF-295 (glioblastoma - human), with inhibitions from 34.98 to 98.63% of cellular growth at a concentration of 5 g/mL. Isoniazid, in turn, hasnt been effective against all cell lines studied. To evaluate the effect of coordinating the metal on the pharmacological activity of hydrazones, complexes of copper (II) and gallium (III) have been synthesized, being all novel compounds: [Cu(HPCIH)Cl2]∙H2O (6), [Cu(HAPIH)Cl2]∙H2O (7), [Cu2(HBPIH)2Cl2]Cl2∙4H2O(8), [Cu(HPAmIH)Cl2]∙H2O (9), [Cu(HPzAmIH)Cl2]∙H2O (10), [Ga(HPCIH)2](NO3)32H2O (11), [Ga(HAPIH)(APIH)](NO3)22H2O (12), [Ga(HPAmIH)(PAmIH)](NO3)22H2O (13) and [Ga(HPzAmIH)(PzAmIH)](NO3)2H2O (14).The complexes have been characterized by IR spectroscopy, NMR, elemental analysis, conductivimetry and electron spectroscopy. In general, these complexes have also shown action against M. tuberculosis, whereas only 6, 9, 10 and 14 have demonstrated better activity than the free hydrazones. The metal complexes have been equally or more active against human the cancer cell lines OVCAR-8, HCT-116 and SF-295 than the free hydrazones. The complexes 79 and 12 deserve to be highlighted, which have shown 72.2100% inhibition of cell growth in the 5 g/mL concentration. The results therefore demonstrate that in general compounds 114 are less active than isoniazid against M. tuberculosis, while chemical modification of the drug, forming hydrazones and subsequent complexation with the copper (II) and gallium(III) metal ions have been an interesting strategy to obtain compounds more potent against tumor cells
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Compostos de coordenação de Ir(III), Re(I) e Ru(II) para aplicações em dispositivos moleculares / Ir(III), Re(I) and Ru(II) coordination compounds towards application in molecular devices

Kassio Papi da Silva Zanoni 01 April 2016 (has links)
Esta tese focou em três tópicos principais: caracterização de filmes compactos de TiO2 e seu comportamento em células solares sensibilizadas por corante; estudo das propriedades fotoquímicas e fotofísicas de um complexo fotoisomerizável de rênio(I); elucidação das propriedades fotofísicas e eletrônicas de complexos de irídio(III) e suas aplicações em dispositivos emissores de luz. Filmes compactos foram automontados nos fotoanodos de células solares sensibilizadas por corante (DSCs), sob o filme mesoporoso de TiO2/corante, utilizando sols de TiO2 ácidos e básicos como cátions e ânions, respectivamente. A obtenção dos sols foi realizada sob controle absoluto para resultar em propriedades morfológicas e ópticas apropriadas para filmes compactos de alta qualidade, como indicado por perfilometria e microscopia eletrônica de transmissão e varredura. As DSCs com bicamadas de TiO2 melhoraram as eficiências de conversão em até 62%. Uma investigação detalhada por parâmetros fotoeletroquímicos, IPCE, tempo de vida do elétron e espectroscopia de impedância eletroquímica demonstrou que o contato entre o vidro condutor (FTO) e o TiO2 é melhorado e que a recombinação de carga no FTO/I3- é diminuída. O novo complexo fac-[Re(CO)3(Ph2phen)(trans-stpyCN)]+ foi sintetizado para apresentar o intercâmbio entre as configurações trans e cis do ligante coordenado por meio de fotoisomerizações eficientes e reversíveis. As fotólises em 313, 334, 365 e404 nm resultam em mudanças espectrais no UV-Vis e RMN atribuídas à fotoisomerização trans-cis do ligante stpyCN coordenado. O processo reverso cis-trans também foi observado com irradiação em 255 nm, com um notável rendimento quântico (&#934 = 0,16), de mesma magnitude que para o processo trans-cis (Φ = 0,38). A caracterização fotofísica e os espectros de absorção do transiente corroboraram na atribuição de um comportamento incomum para os estados excitados quasedegenerados 3ILstpyCN e 3MLCTRe→Ph2phen. Complexos heterolépticos de Ir(III) foram sintetizados e suas propriedades fotofísicas avaliadas, como rendimentos quânticos e tempos de vida de emissão, constantes radiativas e não-radiativas e coordenadas CIE. Os parâmetros fotofísicos variaram sistematicamente com variações nos substituintes retiradores ou doares de elétrons, como corroborado por cálculos TD-DFT, que mostraram uma mistura de estados excitados IL-MLCT. Três desses complexos foram utilizados na camada ativa de dispositivos emissores de luz e caracterizados optoeletronicamente por curvas de corrente-brilho-potencial e espectros eletroluminescentes. / Three main topics are discussed in this thesis: characterization of TiO2 compact films towards high-performance dye-sensitized solar cells; investigations of photophysical and photochemical processes of a Re(I) complex; photophysical elucidation of Ir(III) complexes and their application in light emitting devices. All-nano-TiO2 compact films were auto-assembled in the photoanodes of dyesensitized solar cells (DSCs), beneath the TiO2 mesoporous film, employing acid and basic nano-TiO2 sols as cations and anions, respectively. TiO2 syntheses were performed under absolute control to lead to appropriate morphological and optical properties to yield high quality compact films, as indicated by profilometry, tunning and scanning electron microscopy. DSCs with TiO2 bilayers on top of the conducting glass (FTO) improved the conversion efficiency up to 62%. A detailed study by photoelectrochemical parameters, IPCE, electron lifetime and electrochemical impedance spectroscopy demonstrates that the contact between FTO and TiO2 was improved and that the FTO/I3- charge recombination was prevented. The novel fac-[Re(CO)3(Ph2phen)(trans-stpyCN)]+ complex was synthesized to show switchable trans-cis configurations of the coordinated stpyCN ligand through efficient and reversible photoassisted isomerizations. Photolyses at 313, 334, 365 and 404 nm led to UV-Vis and NMR spectral changes ascribed to the trans-to-cis photoisomerization of the coordinated ligand. The reverse cis-to-trans process was alsoobserved at 255 nm irradiation, with a remarkable quantum yield (Φ = 0.16), in the same magnitude to the one for trans-to-cis photoprocess (Φ = 0.38). Photophysical characterization and transient absorption spectra provided insights on the light-driven trans ? cis pathways and indicated an unusual behavior for the 3ILstpyCN excited state, induced by an interplay with the quasi-degenerated 3MLCTRePh2phen state. Heteroleptic Ir(III) complexes were synthesized and phophysical properties evaluated, such as emission quantum yields and lifetimes, radiative and non-radiative constants and CIE coordinates. The photophysical parameters varied systematically with variations in electron-donating or -withdrawing substituents on the ligands, as corroborated by TD-DFT calculations that showed an IL-MLCT mixing in their emissive excited state. Three complexes were employed in the active layer of light emitting devices and had their optoeletronic properties characterized by current-brightness-voltage curves and electroluminescent spectra.
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Molecular tectonics : heterometallic coordination networks based on chiral luminescent Ir(III) complexes / Tectonique moléculaire : réseaux de coordination hétérométalliques basés sur des complexes d'Iridium(III) chiraux et luminescents

Xu, Chaojie 13 October 2015 (has links)
Les réseaux de coordination sont des architectures cristallines hybrides organiques-inorganiques pouvant présenter des propriétés découlant de leurs compositions et de leurs architectures. L’objectif de ce travail fut la synthèse de réseaux de coordination hétérométalliques à base de complexes d’Iridium (III) chiraux et luminescents.Dans un premier temps, la synthèse de nouveaux complexes d’Iridium cationiques bis-cyclométallés sous forme racémique et énantiopure a été réalisée avec succès. L'étude de leurs propriétés photophysiques a montré une émission dans le rouge par excitation dans le visible. La formation de réseaux de coordination à partir de ces métallatectons cationiques a ensuite été étudiée. Un réseau de coordination homochiral monodimensionnel luminescent a notamment été obtenu via l’auto-assemblage d'un complexe énantiopure avec un sel de cadmium(II). D’autre part, la synthèse de complexes d’Iridium neutres tris-cyclométallés possédant un troisième ligand dérivé de l’unité 2-phénylpyridine comportant des sites de coordination périphériques a été optimisée et les propriétés photophysiques de ces complexes discrets ont été étudiées. L'utilisation de ces complexes comme métallatectons neutres a conduit à la formation de différents réseaux de coordination luminescents. / Coordination networks or Metal Organic Frameworks (MOFs) are hybrid organic–inorganic crystalline architectures that, depending on their composition and organization, may display tailored properties. The aim of this PhD work was to synthesize heterometallic coordination networks based on chiral luminescent Iridium(III) complexes. On the one hand, the synthesis of cationic bis-cyclometallated Ir(III) complexes, both as racemate and as enantiopure species, was achieved. These complexes display red emission upon excitation in the visible domain. Formation of coordination networks using the prepared cationic metallatectons was studied. Notably, a luminescent enantiopure 1D coordination network was obtained upon self-assembly of one of the enantiopure cationic metallatectons with Cd(II) salts. On the other hand, synthesis of racemic neutral tris-cyclometallated Ir(III) complexes was also optimized and their photophysical properties studied. Different coordination networks have been also generated and studied.
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Periferní funkcionalizace polydentátních Schiffových ligandů pro přípravu biologicky aktivních komplexů Fe(III) a Co(III) / Peripheral functionalization of polydentate Schiff ligands for preparation of biologically active Fe(III) and Co(III) complexes

Kotásková, Lucie January 2020 (has links)
Diploma thesis deals with preparation of peripherally functionalized polydentate Schiff ligands, suitable for metal coordination, such as Fe(III) or Co(III). The compounds, formed by this functionalization using organic molecule or stable organic radical, provide coordination site for another central atom. The compounds were synthesized for their potential biological activity. The organic ligands series was prepared, and these ligands were submitted to coordination reactions with selected transition metals. The prepared compounds were characterized by nuclear magnetic resonance, mass spectrometry, electron paramagnetic resonance and X-ray structure analysis.
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Spectroscopie Raman de complexes de fer(II) et fer(III) à transition de spin

Rollet, Frédéric-Guillaume 06 1900 (has links)
Les transitions de spin provoquent des changements de propriétés physiques des complexes de métaux du bloc d les subissant, notamment de leur structure et propriétés spectroscopiques. Ce mémoire porte sur la spectroscopie Raman de composés du fer(II) et du fer(III), pour lesquels on induit une transition de spin par variation de la température ou de la pression. Trois complexes de fer(II) de type FeN4(NCS)2 avec des comportements de transition de spin différents ont été étudiés : Fe(Phen)2(NCS)2 (Phen : 1,10-Phénanthroline), Fe(Btz)2(NCS)2 (Btz : 2,2’-bi-4,5-dihydrothiazine) et Fe(pyridine)4(NCS)2. Un décalage de l’ordre de 50 cm-1 est observable pour la fréquence d’étirement C-N du ligand thiocyanate des complexes FeN4(NCS)2, lors de la transition de spin induite par variation de la température ou de la pression. Il est possible d’utiliser cette variation de fréquence afin de tracer un profil de transition. Quatre complexes isomères de type FeL222(CN)2 (L222 : 2,13- diméthyl-6,9-dioxa-3,12,18-triazabicyclo[12.3.1]-octadéca-1(18),2,12,14,16-pentaène) ont également été étudiés. Un taux de décalage de l’ordre d’environ 0,03 cm-1/K est observé pour plusieurs bandes du complexe FeL222(CN)2. La bande à 1415 cm-1 disparaît à plus haute température au profit d’une bande à 1400 cm-1. Pour le complexe de chiralité R,R’, les bandes à 1008 cm-1 et 1140 cm-1 se déplacent vers des fréquences plus élevées à partir de 223 K. Les transitions de spin sont observées dans certains complexes de fer(III). Dans cette famille de composés, le complexe Fe(EtDTC)3 (EtDTC : N,N-diéthyldithiocarbamate) a été étudié . Aucun changement n’a été observé dans l’intensité des bandes d’étirement fer-soufre sur les spectres à température variable. Cependant, la bande Fe-S associée à la forme bas-spin à 530 cm-1 augmente en intensité au profit de la bande associée à la forme haut-spin à 350 cm-1 lors des mesures à haute pression, passant d’un rapport d’amplitude de 50% à pression ambiante à 80% à 21 kbar. Un dédoublement de la bande d’étirement C-N du ligand dithiocarbamate à 1495 cm-1 est également observé à des pressions supérieures à 5 kbar. Une comparaison des changements des fréquences de vibration de tous les complexes est effectuée. / AbstractSpin crossover processes lead to significant changes of molecular structures and spectroscopic properties measured for complexes of d-block transition metals. This thesis focuses on vibrational Raman spectroscopy of iron(II) and iron(III) compounds with spin transitions induced through temperature and pressure variations. Three iron(II) complexes of type FeN4(NCS)2 with different spin transition patterns have been studied: Fe(Phen)2(NCS)2 (Phen : 1,10-Phenanthroline), Fe(Btz)2(NCS)2 (Btz : 2,2’-bi-4,5- dihydrothiazine) and Fe(pyridine)4(NCS)2. A 50 cm-1 shift has been found for the C-N stretching frequency of the thiocyanate ligand in these compounds as a consequence of the spin transition induced by temperature or pressure. These frequency variations have been used to trace different transition profiles. Four different isomers of FeL222(CN)2 (L222 : [2,13-dimethyl-6,9-dioxa-3,12,18-triazabicyclo[12.3.1]-octadeca-1(18),2,12,14,16- pentaene]) type complexes have also been studied. A variation with temperature of approximately 0,03 cm-1/K has been observed for a few bands for the FeL222(CN)2 complex. A band at 1415 cm-1 decreases in intensity in favour of a band at 1400 cm-1 as temperature rises. The bands at 1008 cm-1 and 1140 cm-1 for the complex of R,R’ configuration shift to higher frequencies around 223 K. Spin transitions have also been investigated in some iron(III) complexes. In this family of compounds, the Fe(EtDTC)3 (EtDTC : N,N-diéthyldithiocarbamate) complex has been studied. No change has been observed in the intensity of the iron-sulphur stretching bands in spectra measured at variable temperature. However, at high pressure the low-spin Fe-S band at 530 cm-1 gains intensity compared to the high spin band at 350 cm-1. A splitting of the C-N stretching band of the dithiocarbamate ligand at 1495 cm-1 is observed at pressures above 5 kbar. A comparison of all changes in vibrational spectra is presented.

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