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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.
81

Charge Transfer And Hydrogen Bonding Interactions In Ferrocenyl Schiff Bases

Pal, Sushanta Kumar 09 1900 (has links) (PDF)
No description available.
82

Synthesis of Ligands and Macrocycles Based on 1,3-Diiminoisoindoline and Study of New Highly Fluorescent and Symmetric Pyrrole-BF<sub>2</sub> Chromophores

Tamgho, Ingrid-Suzy January 2014 (has links)
No description available.
83

Synthesis, characterization, and evaluation of silica and polymer supported catalysts for the production of fine chemicals

Shiels, Rebecca Anne 05 May 2008 (has links)
Catalysis is an important field of study in chemical engineering and chemistry due to its application in a vast number of chemical transformations. Traditionally, catalysts have been developed as homogeneous molecular species or as heterogeneous insoluble materials. While homogeneous catalysts are typically very active and selective, they are difficult to recover. Conversely, heterogeneous catalysts are easy to recover and reuse, but they generally are less selective. To address these issues, the immobilization of homogeneous catalyst analogs onto solid supports has been a subject of research for the past few decades. Nonetheless, the effects of immobilization are still not completely predictable, and so continued effort is required to develop new immobilized catalysts as well as to develop a better understanding of how different parameters affect catalytic behavior. This dissertation presents the synthesis, characterization, and evaluation of new immobilized catalysts for different applications. First, a solid base catalyst supported on silica was developed and studied in the synthesis of cyclic carbonates from epoxides and carbon dioxide. Next, polymer and silica supported vanadium Schiff base catalysts were developed and evaluated for use in the oxidative kinetic resolution of alpha-hydroxy esters, an enantioselective reaction. Lastly, salen catalyst analogs with amine reactive functional groups were synthesized and characterized for grafting onto aminosilicas with different degrees of amine group isolation. The grafted catalysts were then tested to determine how catalyst spacing on the surface affects their behavior. Throughout the presentation of these results, comparisons are made amongst the new supported catalysts and relevant existing catalysts to discern general trends which could be applied to a wider range of immobilized catalysts. Finally, research opportunities for further improvements in these areas are suggested.
84

Complexos mono- e bimetálicos de cobre(II) e de cobalto(III) com bases de Schiff tridentadas e tetradentadas : Sínteses, caracterizações e estudos em reações catalíticas / Mono- and bimetallic complexes of copper(II) and of cobalt(III) with tridentate and tetradentate schiff bases : synthesis, characterizations and studies in catalytic reactions

Bucalon, Daniel Haguihara 20 May 2014 (has links)
Submitted by Daniele Amaral (daniee_ni@hotmail.com) on 2016-09-15T11:44:18Z No. of bitstreams: 1 DissDHB.pdf: 9941322 bytes, checksum: e5fee8012d9157d5ea6933c054636a3f (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-16T19:49:36Z (GMT) No. of bitstreams: 1 DissDHB.pdf: 9941322 bytes, checksum: e5fee8012d9157d5ea6933c054636a3f (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-16T19:49:44Z (GMT) No. of bitstreams: 1 DissDHB.pdf: 9941322 bytes, checksum: e5fee8012d9157d5ea6933c054636a3f (MD5) / Made available in DSpace on 2016-09-16T19:49:50Z (GMT). No. of bitstreams: 1 DissDHB.pdf: 9941322 bytes, checksum: e5fee8012d9157d5ea6933c054636a3f (MD5) Previous issue date: 2014-05-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / This dissertation details the synthesis with satisfactory reaction yields (between 56.3 and 96.5%) of mono- and bimetallic complexes of copper(II) and of cobalt(III), containing as ligands, tridentate and tetradentate Schiff bases. The compounds were characterized, for different techniques, such as melting point, elemental analysis, solubility in various solvents, conductometry, nuclear magnetic resonance (NMR) spectroscopy and spectroscopy in region of the IR and in the UVvis. The results of melting point indicate that the compounds have high purity and the elemental analysis showed consistent values. The solubility tests indicate different capabilities of intermolecular interactions and labilization distinct between the compounds. The obtained molar conductivities in electrolyte solution indicate proportions expected by the proposed structures. The obtained data by 1H and 13C NMR in compounds with cobalt(III) showed concordance with the proposed structures in solution. The spectra of the compounds in the IV region show proper bands, referring to the stretch of C=N bond, in the range of 1600-1650 cm-1, stretches relating to the bonds of the metal ion with the oxygen of the phenolate group, with chlorides and with the nitrogen atoms of the imine, amine groups, the imidazole and imidazolate were evidenced, besides to help differentiation of monometallic and bimetallic compounds. In the UV-vis region measured spectra were verified the presence of bands that should correspond to the electronic transitions of π → π* type which involve the molecular orbitals imine group (C=N), of bands d-d transitions due to the metal ion present also, but related transitions to the n→π* type were not verified. The compounds were tested as a catalyst in the oxidation of 3,5-DTBC and in studies of catalytic oxidation using O2 at 25°C were obtained values of enzyme kinetics parameters and these values are comparable with the literature, kcat = 1.28 x 10-1 s-1 εcat = 6.79 x 102 L mol-1 s-1 for CuCu3EtOtetraB (best of the series), there is evidence that the mechanism is different for each used complex. / Esta dissertação detalha as sínteses com rendimentos reacionais satisfatórios (entre 56,3 e 96,5%) de complexos mono- e bimetálicos de cobre(II) e de cobalto(III), contendo como ligantes, bases de Schiff tridentadas e tetradentadas. Os compostos foram caracterizados por diferentes técnicas, como ponto de fusão, análise elementar, solubilidades em diversos solventes, condutometria, espectroscopia de ressonância magnética nuclear (RMN) e espectroscopias na região do IV e do UV-vis. Os resultados de ponto de fusão indicam que os compostos tem alto grau de pureza e as análises elementares indicam valores coerentes. Os testes de solubilidades indicam capacidades de interações intermoleculares e de labilizações distintas entre os compostos. Os dados de condutividades molares em solução indicam as proporções de eletrólito previstas pelas estruturas propostas. Os dados obtidos pela RMN de 1H e 13C nos compostos de cobalto(III) mostram concordâncias com as estruturas propostas em solução. Os espectros dos compostos na região do IV evidenciam bandas peculiares como estiramento da ligação C=N, na faixa de 1600-1650 cm-1, estiramentos referentes às ligações do íon metálico com o oxigênio do grupo fenolato, com os cloros e com os nitrogênios dos grupos imina, amina, do imidazol e do imidazolato, além de auxiliar na diferenciação dos compostos monometálicos e bimetálicos. Nos espectros medidos na região do UV-vis foram verificadas as presenças de bandas que devem corresponder às transições eletrônicas do tipo π → π* nas quais envolvem os orbitais moleculares do grupo iminia (C=N), das bandas relativas às transições d-d devido ao íon metálico presente, e das transições do tipo n → π* da imina que não foram verificadas. Os compostos foram testados como catalisador na oxidação do 3,5-DTBC e nos estudos da oxidação catalítica usando O2 a 25ºC foram obtidos valores dos parâmetros de cinética enzimática e estes valores são comparáveis com a literatura, kcat = 1,28 x 10-1 s-1, εcat = 6,79 x 102 L mol-1 s-1 para CuCu3EtOtetraB (melhor da série), indícios de que o mecanismo seja diferente para cada complexo utilizado foram verificados.
85

Complexos de rutênio(III) com bases de Schiff tridentadas e tetradentadas do tipo Salophen : potenciais catalisadores na oxidação de catecol / Ruthenium (III) complexes with tridentate and tetradentate salophen type Schiff bases : Potential catalysts in the oxidation of catechol.

Katayama, Juliana Midori Toia 09 September 2015 (has links)
Submitted by Izabel Franco (izabel-franco@ufscar.br) on 2016-09-23T20:28:33Z No. of bitstreams: 1 DissJMTK.pdf: 2219272 bytes, checksum: 9f24a292820e6aa9d2d9655ba3b87701 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-26T20:46:39Z (GMT) No. of bitstreams: 1 DissJMTK.pdf: 2219272 bytes, checksum: 9f24a292820e6aa9d2d9655ba3b87701 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-09-26T20:46:47Z (GMT) No. of bitstreams: 1 DissJMTK.pdf: 2219272 bytes, checksum: 9f24a292820e6aa9d2d9655ba3b87701 (MD5) / Made available in DSpace on 2016-09-26T20:46:54Z (GMT). No. of bitstreams: 1 DissJMTK.pdf: 2219272 bytes, checksum: 9f24a292820e6aa9d2d9655ba3b87701 (MD5) Previous issue date: 2015-09-09 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Ruthenium complexes are known as versatile electron-transfer and energy-transfer compounds. Due to these unique characteristics, ruthenium complexes exhibit a wide range of applications in various research areas such as artificial photosynthesis, photomolecular devices, biological probes, oxidation catalysts and organic synthesis. In the last two decades, salophen ligands and their complexes have received much attention, mainly because of their extensive applications in the fields of synthesis and catalysis. Thus, ruthenium(III) complexes with Schiff bases have several potential applications in the catalytic reactions such as cyclopropanation, epoxidation, aziridination, sulfimidation, catechols oxidation and Diels-Alder reactions. In this work were synthesized ligands and ruthenium complexes containing tridentate and tetradentate Schiff bases, which have substituted aromatic diimines, with satisfactory yields. The compounds synthesized in this work were characterized by melting point measurements, solubility tests, conductivity measurements, vibrational spectroscopy in the IR region, absorption spectra in the UV-vis, and cyclic voltammetry. The ligands were also characterized by nuclear magnetic resonance. The synthesized complex catalyzed oxidation of the substrate, 3,5-di-tert-butylcatechol, in their respective quinone; and these transformations were accompanied by absorption spectroscopy in the UV-vis region in 24 hours of reaction. The complexes’ structures have allowed structural and electronic effects to be evaluated and correlated with their catalytic activities. Although slow and low substrate conversion, less than 30%, trends were observed for correlations between structure and catalytic activity. The percentages of 3,5-di-tert-butilquinone obtained for the best catalysts among these complexes suggests that there is a step of forming a catalytically active species during the reaction time. / Complexos de rutênio são conhecidos como compostos versáteis na transferência de elétrons e de energia. Devido a estas características únicas, complexos de rutênio apresentam uma vasta gama de aplicações em diversas áreas de pesquisa, como a fotossíntese artificial, dispositivos fotomoleculares, sondas biológicas, catalisadores de oxidação e síntese orgânica. Nas últimas duas décadas, os ligantes do tipo salophen e seus complexos têm recebido muita atenção, principalmente por causa de suas inúmeras aplicações nos domínios da síntese e catálise. Diante disso, complexos de rutênio(III) com bases de Schiff apresentam várias possibilidades de aplicações em reações catalíticas como: ciclopropanação, epoxidação, aziridinação, sulfimidação, oxidação de catecóis e reações Diels-Alder. Nesse trabalho foram sintetizados ligantes e complexos de rutênio contendo bases de Schiff tridentadas e tetradentadas, os quais apresentam diiminas aromáticas substituídas, com rendimentos satisfatórios. Esses compostos sintetizados foram caracterizados por ponto de fusão, solubilidade, medidas de condutividade, espectroscopia vibracional na região do IV, espectroscopia de absorção na região do UV-vis e voltametria cíclica; sendo que os ligantes também foram caracterizados por Ressonância Magnética Nuclear. Os complexos sintetizados catalisaram a oxidação do substrato, 3,5-di-terc-butilcatecol, em sua respectiva quinona; sendo essas transformações acompanhadas por espectroscopia de absorção da região do UV-vis em 24 horas de reação. As estruturas dos complexos permitiram que efeitos estruturais e eletrônicos pudessem ser avaliados e correlacionados com suas as atividades catalíticas. Apesar de lentas e das baixas conversões de substrato, inferiores a 30%, tendências foram constatadas por correlações entre estrutura e atividades catalíticas. As porcentagens de 3,5-di-tercbutilquinona obtidas para os melhores catalisadores dentre esses complexos sugere que há uma etapa de formação de uma espécie cataliticamente ativa durante o tempo reacional.
86

A bioinorganic investigation of some metal complexes of the Schiff base, N,N'-bis(3-methoxysalicylaldimine)propan-2-ol

Mopp, Estelle 13 April 2012 (has links)
This thesis includes the synthesis, characterisation, antioxidant and antimicrobial activities of Cu(II)-, Co(II)- and Co(III) complexes with N,N'-bis(3- methoxysalicylaldimine)propan-2-ol, 2-OH-oVANPN. The Schiff base ligand, 2-OHoVANPN, is derived from o-vanillin and 1,3-diaminopropan-2-ol. The o-vanillin condensed with 1,3-diaminopropan-2-ol in a 2:1 molar ratio yields this potential tetraor pentadentate ligand. The complexes synthesized are tetra (or penta or hexa) coordinated. Formation of the complexes is symbolized as follows:- MX₂ + 2-OH-oVANPN (2:1) -> [M(2-OH-oVANPN)Xn] + HnX MX₂ + 2-OH-oVANPN (2:1) -> [Mn(2-OH-oVANPN)OH] + H₂X₂ MX₂ + (o-vanillin : diaminopropanol) (1:1) -> [M(1:1)X₂] MX₂ + (o-vanillin : diaminopropanol) (1:1) -> [M₃(1:1)X₄] M = Cu(II), Co(II) or Co(III); X = Cl; n = 1, 2. Their structural features have been deduced from their elemental analytical data, IR spectral data, and electronic spectral data. With the exception of {Cu₃(C₁₁H₁₄N₂O₃)(Cl)₄(H₂O)₆}(A4), the Cu(II) complexes were monomeric with 2-OH-oVANPN acting as a tetradentate ligand. A binuclear Co(II) complex, [Co₂(C₁₉H₁₉N₂O₅)(OH)] (B1), was synthesised and the rest of the Co(II) and Co(III) complexes were monomeric with chloride ions coordinating to the metal centre in some cases. Electronic data suggest that the cobalt(II) complexes have octahedral geometries and the copper(II) complexes have square planar structures – Co(III) is likely to be octahedral. Thermal analyses, which included the copper-block-method for determining sublimation temperatures, revealed that some copper(II) and cobalt(II) complexes are hygroscopic and sublime at 200 °C and below. DSC analyses of the Cu(II) complexes gave exotherms around 300 °C for complexes K[Cu(C₁₉H₂₀N₂O₅)(OH)]·2H₂O (A1) and [Cu(C₁₁H15N₂O₃)(Cl)₂]·2H₂O (A2) and above 400 °C for [Cu(C₁₁H₁₆N₂O₃)(Cl)₂] (A3) and {Cu₃(C₁₁H₁₄N₂O₃)(Cl)₄(H₂O)₆} (A4). Antioxidant studies were carried out against the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH·). The cobalt(II) complex, [Co₂(C₁₉H₁₉N₂O₅)(OH)] (B1), which was synthesized in the presence of KOH, had no antioxidant activity, whilst the other cobalt(II) complexes, [Co(C₁₇H₁₇N₂O₅(Cl))]·1½H₂O (B2), [Co(C₁₉H₂₂N₂O₅) (Cl)₂]·5½H₂O (B3) and [Co(C₁₉H₂₂N₂O₅)(Cl)₂]·5½H₂O (B4), which were synthesised in the absence of KOH, demonstrated antioxidant activity. The latter complexes are candidates for cancer cell line testing, while [Cu(C₁₁H₁₆N₂O₃)(Cl)₂] (A3), {Cu₃(C₁₁H₁₄N₂O₃)(Cl)₄(H₂O)₆} (A4), [Co(C₁₉H₂₁N₂O₅)(Cl)₂ ]·5H₂O (C2) and [Co(C₁₉H₂₀N₂O₅)(Cl)]·3H₂O (C3) may show anticancer activity through possible hydrolysis products. Most of the complexes synthesized displayed antimicrobial activity against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Aspergillus niger and Candida albicans. The results indicated that complexes [Cu(C₁₁H₁₆N₂O₃)(Cl)₂](A3), [Co(C₁₉H₂₂N₂O₅)(Cl)₂]·5½H₂O (B3) and [Co(C₁₉H₂₁N₂O₅)(Cl)₂ ]·5H₂O (C2) are active against the Gram-negative Ps. aeruginosa and that the ligand, 2-OH-oVANPN, did not have any activity. The same trend was observed with 2-OH-oVANPN, {Cu₃(C₁₁H₁₄N₂O₃)(Cl)4(H₂O)₆} (A4) and [Co(C₁₉H₂₀N₂O₅)(Cl)]·3H₂O (C3) against the Gram-positive S. aureus. As for activity against E. coli and C. albicans, some complexes showed more activity than the ligand. There is an observed trend here that the metal complexes are more active (toxic) than the corresponding ligand, which is in agreement with Tweedy’s chelation theory.
87

Síntese, caracterização e avaliação biológica de complexos de vanádio e de ouro com bases de Schiff e benzimidazóis

Mota, Vinicius Zamprogno 28 February 2012 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-07-11T20:15:29Z No. of bitstreams: 1 viniciuszamprognomota.pdf: 2945652 bytes, checksum: 2543aba1c0b97eaf6ce52fe22b1d8f33 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-07-13T16:38:27Z (GMT) No. of bitstreams: 1 viniciuszamprognomota.pdf: 2945652 bytes, checksum: 2543aba1c0b97eaf6ce52fe22b1d8f33 (MD5) / Made available in DSpace on 2016-07-13T16:38:27Z (GMT). No. of bitstreams: 1 viniciuszamprognomota.pdf: 2945652 bytes, checksum: 2543aba1c0b97eaf6ce52fe22b1d8f33 (MD5) Previous issue date: 2012-02-28 / Certos íons metálicos bem como seus complexos estão presentes em sistemas biológicos exercendo importantes funções biológicas. No entanto, a utilização dos íons metálicos e de seus compostos, no início, era de modo empírico. A investigação sistemática científica de complexos parece ter vindo somente após os estudos de Paul Ehrlich e Robert Koch. Bases de Schiff diimínicas, assim como seus derivados benzimidazóis, possuem atividades biológicas conhecidas. Alguns complexos contendo vanádio (IV ou V) e de ouro (I ou III) também possuem reconhecidos usos biológicos. Portanto, complexos envolvendo as Bases de Schiff diíminicas e benzimidazóis com íons metálicos de vanádio e de ouro é um importante tema de estudo dentro do campo da Química Bioinorgânica. Dentro deste contexto, este trabalho tratou da síntese e caracterização de bases de Schiff diimínicas e benzimidazóis obtidos a partir da condensação entre 1,2-fenilenodiamina e benzaldeído ou seus derivados. Este trabalho também relata a síntese, caracterização e estudo biológico de complexos envolvendo bases de Schiff diimínicas e benzimidazóis obtidos com os íons de vanádio (IV) e de ouro (I e III). Ao final, são relatados quatorze compostos, sendo seis ligantes e oito complexos. Sete destes compostos ainda não foram relatados na literatura. Os compostos, exceto IMOH e [AuIIMOMeCl], foram testados contra protozoários do gênero Leishmania na etapa promastigota, sendo as espécies L. amazonesis, L. braziliensis, L. chagasi e L major. Os resultados mais expressivos foram encontrados para os compostos envolvendo o íon AuIII. Os complexos de AuIII também foram testados contra a fase amastigota do parasita contra as espécies L. amazonesis, L. braziliensis e L major. / The metal ions and their complexes are present in biological systems exersing important biological functions. However, the use of metal ions and their compounds, it was empirically. Systematic investigation of metals complexes seems to have come only after the studies of Paul Ehrlich and RobertKoch. Diiminics Schiff bases, as well as benzimidazole derivatives, have known biological activities. Some complexes containing vanadium (IV or V) and gold (I or III) also have recognized biological uses. Therefore, complexes involving Schiff Bases diíminicas and benzimidazole metal ions vanadium and gold is a major field of study within the field of Bioinorganic Chemistry. Within this context, this paper deals with the synthesis and characterization of Schiff bases and diimínicas benzimidazole obtained from the condensation between benzaldehyde and 1,2-phenylenediamine or its derivatives. This paper also reports the synthesis, characterization and biological study of complexes involving Schiff bases and diimínicas benzimidazole obtained with ions of vanadium (IV) and gold (I and III). In the end, fourteen compounds are reported, six and eight ligand complexes. Seven of these compounds have not been reported in the literature. The compounds, except IMOH and [AuIIMOMeCl], were tested against the protozoa of the Leishmania promastigote stage, with the species L. amazonesis, L. braziliensis, L. chagasi and L major. The most significant results were found for compounds involving ion AuIII. The AuIII complexes were also tested against the amastigote stage of the parasite species against L. amazonesis, L. braziliensis and L major.
88

Síntese de derivados aminoquinolínicos e avaliação do efeito em protozoários

Souza, Isabela de Oliveira 07 March 2017 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-05-25T14:41:06Z No. of bitstreams: 1 isabeladeoliveirasouza.pdf: 8840752 bytes, checksum: de1f7daf9c0f6025ccc57475de168c79 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-05-25T14:48:39Z (GMT) No. of bitstreams: 1 isabeladeoliveirasouza.pdf: 8840752 bytes, checksum: de1f7daf9c0f6025ccc57475de168c79 (MD5) / Made available in DSpace on 2017-05-25T14:48:39Z (GMT). No. of bitstreams: 1 isabeladeoliveirasouza.pdf: 8840752 bytes, checksum: de1f7daf9c0f6025ccc57475de168c79 (MD5) Previous issue date: 2017-03-07 / Este trabalho mostra a síntese de 26 derivados aminoquinolínicos e suas avaliações em protozoários. Para uma melhor apresentação do projeto este foi dividido em três séries: a primeira está relacionada à síntese de hidrazonas e a segunda à síntese de bases de Schiff. Os dois núcleos bioativos foram conjugados envolvendo o conceito de hibridação molecular. Já a terceira série envolveu a síntese de complexos de prata, a partir dos ligantes 4-aminoquinolínicos. Todos os compostos foram devidamente caracterizados utilizando técnicas espectroscópicas que permitiram a identificação dos mesmos. Os compostos sintetizados tiveram seu potencial antiparasitário avaliado em parasitos do gênero Leishmania e Plasmodium, que são responsáveis pelas doenças Leishmanioses e Malária, respectivamente. Além disto, tiveram sua toxidez avaliada em células de mamíferos, tendo sido escolhidos macrófagos peritoneais de camundongos. Em relação à atividade leishmanicida, parte dos compostos foram ativos em Leishmania sp, com destaque para o composto 1a em formas amastigotas de L. amazonensis (CI50 de 8,1 µM), resultado próximo ao fármaco utilizado como referência, Miltefosina (CI50 de 4,15µM). A maioria dos compostos não apresentou citotoxicidade expressiva para os macrófagos, com exceção dos compostos 1b, 1f e 2d. Os testes em Plasmodium ainda estão em fase de análise. Os resultados aqui apresentados confirmam o potencial biológico de derivados aminoquinolinas e estimulam a continuidade dos estudos com esta classe de moléculas para o tratamento de doenças parasitárias. / This work demonstrates the synthesis of 26 aminoquinolinic derivatives and their evaluation in protozoa. For a better display, the project was divided into three series: the first is related to hydrazone synthesis and the second to synthesis of Schiff bases. The two bioactive nuclei were conjugated involving the concept of molecular hybridization. The third series involved the synthesis of silver complexes from the 4-aminoquinoline ligands. All components were properly characterized using spectroscopic techniques that allowed their identification. The synthesized compounds had their antiparasitic potential evaluated in parasites of the genus Leishmania and Plasmodium, which are responsible for Leishmaniasis and Malaria, respectively. In addition, their toxicity was evaluated in mammalian cells using murine peritoneal macrophages. Regarding the leishmanicidal activity, part of the compounds presented activity against Leishmania sp, with emphasis on compound 1a in amastigotes of L. amazonensis (IC 50 of 8.1 μM), a close result to the reference drug Miltefosine (IC 50 of 4.15 μM). Most compounds did not present expressive cytotoxicity for macrophages, except for compounds 1b, 1f and 2d. Plasmodium tests are still under review. These results confirm the potential biological of aminoquinoline derivatives and stimulate further studies with this class of molecules for the treatment of parasitic diseases.
89

Síntese, caracterização e estrutura cristalina de redes metalorgânicas com ligantes mistos N- e O- doadores

Flores, Leonã da Silva 21 August 2015 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-01-05T09:56:54Z No. of bitstreams: 1 leonadasilvaflores.pdf: 7703560 bytes, checksum: 6e5f7330b9f5bb6e7d5e649e91d606e6 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-01-25T16:05:33Z (GMT) No. of bitstreams: 1 leonadasilvaflores.pdf: 7703560 bytes, checksum: 6e5f7330b9f5bb6e7d5e649e91d606e6 (MD5) / Made available in DSpace on 2016-01-25T16:05:33Z (GMT). No. of bitstreams: 1 leonadasilvaflores.pdf: 7703560 bytes, checksum: 6e5f7330b9f5bb6e7d5e649e91d606e6 (MD5) Previous issue date: 2015-08-21 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O objetivo deste trabalho foi o de sintetizar MOFs com ligantes mistos, N- e O- doadores, utilizando alguns cátions metálicos da primeira série de transição como conectores de rede. Foram obtidas as redes de coordenação CoPDC2D e ZnPDC2D, que são isoestruturas as quais se estendem bi-dimensionalmente. Essas formam laços com 16-circuitos (circuitos mais curtos que contemplam 16 átomos), e incluem apenas o ligante 2,5-piridinodicarboxilato 2,5-pdc e os cátions (Co2+ e Zn2+) na coordenação. Algumas diferenças entre as sínteses aqui reportadas e aquelas publicadas são mostradas. Este trabalho também reporta brevemente o estudo topológico dessas redes bidimensionais. Todavia, foi obtida uma nova rede de coordenação ZnPDC1D, envolvendo a formação de laço (circuitos mais curtos de átomos), os quais se estendem unidimensionalmente, e envolvem os cátions Zn2+ e o ligante 2,5-pdc. Além disso, foi reportada uma série de novos complexos CuPDC0D, MnPDC0D, CuPDC0Dq e CuPDC0Dr, aniônicos, envolvendo apenas o ligante 2,5-pdc e os íons Cu2+ e Mn2+. Estes sistemas formam monômeros, MnPDC0D e CuPDC0Dr, ou dímeros oxo-metalatos, CuPDC0D e CuPDC0Dq, e contemplam cátions etilenodimina na rede cristalina, formando complexos metálicos (no caso do CuPDC0Dq. Finalmente, faz-se uma discussão sobre os ligantes nitrogenados 1,2-bis(2-piridil)etilenediamina 2-bpen e 1,2-bis(4-piridil)etilenediamina 4-bpen, que foram sintetizados, porém não foi observada a coordenação destes em nenhum dos sistemas aqui reportados. Tal fato foi atribuído à hidrólise dos ligantes nitrogenados (Bases de Schiff) e, portanto, foi proposto um mecanismo para essa hidrólise nos sistemas obtidos. A estrutura cristalina do ligante 2-bpen, ainda não reportada na literatura, foi discutida. / The aim of this work was the synthesis of MOFs with mixed ligands N- and O- donors from some metal cations of first series transition, as connectors of the net. In this work has been obtained coordination networks CoPDC2D and ZnPDC2D, that are iso-structures, which extend two-dimensionally forming loops with 16-shortest circuits, including the ligand 2,5-pyridinedicarboxylate 2,5-pdc and the Co2+ and Zn2+ cations, respectively. Both structures were recently published, however there some differences between the syntheses and the yield. Moreover, this work reports briefly the topological study of these two-dimensional networks. Additionally, were obtained a new coordination network ZnPDC1D, including loops formation, which extend one-dimensionally containing the cation Zn2+ and 2,5-pdc ligand. Here, were reported a series of new complexes CuPDC0D, MnPDC0D, CuPDC0Dq and CuPDC0Dr, anionic, including just the 2-5-pdc ligand and some this having Cu2+ e Mn2+ ions. This systems are monomers MnPDC0D and CuPDC0Dr or oxometalates dimmers CuPDC0D and CuPDC0Dq, including etilenodiamine on the crystalline network and, in some cases, participating on coordination CoPDC0Dq. Finally, are discussed about the nitrogenous ligands 1,2-bis(2-pyridil)etilenediamine 2-bpen and 1,2-bis(4-pyridil)etilenediamine 4-bpen, that were synthesized and characterized but not was observed the coordination in any system here reported. This has been attributed to the hydrolysis of nitrogenous ligands and, therefore, was proposed a mechanism for hydrolysis of these systems. The crystal structure of ligand 2-bpen, not yet reported in literature, was discussed.
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Desenvolvimento de métodos voltamétricos para a quantificação de LSD utilizando-se o eletrodo de pasta de carbono modificado com complexo de base de Schiff / Development of voltammetric methods for the quantification of LSD using a carbon paste electrode modified by a Schiff base complex

Ribeiro, Maria Fernanda Muzetti 29 October 2015 (has links)
Nos últimos anos, vários métodos eletroanalíticos foram desenvolvidos a fim de tornarem mais práticas e acessíveis às análises químicas de substâncias entorpecentes realizadas pela polícia científica. Com a sensibilidade e seletividade compatíveis com as dos métodos instrumentais convencionais, é a portabilidade da técnica eletroanalítica que se sobressai e tem apresentado grande potencial para tais aplicações. O uso de complexos metálicos com as bases de Schiff como modificadores do eletrodo de trabalho, tornou ainda mais promissora a utilização destes métodos para a detecção e quantificação de entorpecentes. Os eletrodos de pasta de carbono também contribuem para a praticidade da eletroanalítica, uma vez que são produzidos de forma simples e barata. Desta forma, neste projeto foram desenvolvidos métodos voltamétricos para a quantificação da dietilamida do ácido lisérgico (LSD), utilizando-se o eletrodo de pasta de carbono modificado com o complexo [UO2(Ac-ophen)]·H2O. A aplicação do KCl como eletrólito suporte, em solução aquosa, diferencia estes métodos do encontrado na literatura. Nas análises, foram empregadas as técnicas de voltametria cíclica, onda quadrada e de pulso diferencial. A linearidade no aumento da corrente frente às variações da concentração do LSD possibilitou a obtenção das curvas analíticas com desvio padrão e limites de detecção e quantificação de 2,45, 0,62 e 1,02 mol L-1, respectivamente, como melhores resultados. As análises de recuperação das amostras, 103 e 108%, demostra a possibilidade da utilização destas no âmbito forense. / The development of electroanalytical methods for forensic science has been growing in recent years by the fact of their practicality and low cost. Once sensibility and selectivity values are compatible to conventional methods, as chromatography and spectrometry, the portability of this system consists on interesting advantages. The simple modification of the carbon paste working electrode with Schiff bases complexes became even more promising to use this method for the detection and quantification of narcotics. The carbon paste electrode itself contributes for the practicality of the analyses, once it is made of simple carbon powder, which can be disposable. This project aimed to develop voltammetric methods for the quantification of the lysergic acid diethylamide (LSD) using a carbon paste electrode modified with the complex [UO2(Ac-ophen)]·H2O. The use of aqueous solution of KCl as supporting electrolyte characterizes a less pollutant methodology, differently of other methods that still use toxic solvents The combination of the differential pulse and square wave voltammetries with the modified carbon paste was crucial for the detection of trace levels of the LSD. The linear response in various concentrations of LSD results on analytical curves with standard deviation, detection, and quantification limits of 2,45, 0,62, 1,02 mol L-1, respectively. And the recovery values of 103 and 108 % indicates the possibility of using this method in the forensic science

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