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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.
31

Atividade antipirética e antiinflamatória de derivados 5-trifluormetil-4,5-diidro-1H-1-carboxiamida pirazol em ratos

Pasin, Juliana Saibt Martins January 2010 (has links)
A febre é um aumento regulado da temperatura corporal central, caracterizada por uma alteração no centro termorregulatório, a qual resulta da interação entre o sistema nervoso central e o imunológico. Enquanto a febre caracteriza lesão celular, infecção e inflamação, ela tem sido considerada o mais importante componente da resposta de fase aguda. Embora existam evidências de que a febre aumenta a defesa do hospedeiro, alguns estudos têm sugerido que o aumento da temperatura central a níveis febris pode ser prejudicial. Portanto, nas situações clínicas nas quais os riscos associados com a febre superam os benefícios, o tratamento antipirético é formalmente indicado. Os derivados pirazolínicos constituem um importante grupo de compostos orgânicos que têm sido extensivamente estudados devido às suas inúmeras atividades biológicas, que incluem atividade antipirética. Recentemente uma série de derivados pirazolínicos inéditos foi avaliada quanto à atividade antiedematogênica e antinociceptiva em camundongos. Estes compostos causam antinocicepção no teste da formalina e no modelo de artrite induzida por adjuvante de Freund, bem como diminuem o edema induzido por carragenina. Dados os efeitos antiinflamatórios descritos para estes compostos, o objetivo do estudo foi investigar o efeito de oito derivados 5-trifluormetil-4,5-diidro- 1H-1-pirazol-1-carboxiamida (TFDPs) sobre a temperatura corporal basal, a febre induzida por S. cerevisiae (0.135 g/Kg, i.p.) e a inflamação peritoneal em ratos Wistar machos de 28 dias de idade. Somente os compostos 3Et- e 3Pr-TFDP (140 e 200 μmol/kg respectivamente, s.c., 4 h após a injeção do S. cerevisiae) atenuaram a febre em 61.0% e 82.4%, respectivamente. Estes dois compostos foram selecionados para a investigação dos mecanismos de ação. Os efeitos sobre a atividade da ciclooxigenase-1 e -2 (COX-1 e COX-2), a oxidação in vitro do 1,1-difenil-2- picrilhidrazil (DPPH), os níveis de TNF-a e IL-1b e influxo de leucócitos na cavidade peritoneal dos ratos injetados com S. cerevisiae foram determinados. Enquanto 3Et- e 3Pr-TFDP não alteraram o aumento nos níveis de TNF-a e IL-1b induzido por S. cerevisiae, o derivado 3Et- TFDP causou uma redução de 42% na contagem de leucócitos na cavidade peritoneal. 3Et- e 3Pr-TFDP não alteraram a atividade da COX-1 e COX-2 in vitro, mas apresentaram atividade antioxidante no ensaio do DPPH, com CI50 de 39.3 (25.0-62.0) mM e 162.9 (135.6-195.7) mM, respectivamente. Em outro grupo de experimentos, foi avaliado o efeito do pré-tratamento dos animais com os compostos 3Et- e 3Pr-TFDP sobre a inflamação peritoneal induzida por S.cerevisiae em ratos. O pré-tratamento com 3Et-TFDP (140 μmol/kg, 5 mL/Kg, s.c.) preveniu significativamente o aumento no influxo de leucócitos, a permeabilidade vascular peritoneal e a atividade da mieloperoxidase (MPO), mas não teve efeito sobre os níveis de TNF-a e IL-1b. Por outro lado, 3Pr-TFDP (200 μmol/kg, 5 mL/Kg, s.c.) não apresentou efeito sobre nenhum desses parâmetros inflamatórios. O presente estudo descreve dois novos derivados pirazolínicos com atividade antipirética, cujos mecanismos de ação não envolvem inibição da COX ou inibição da liberação de citocinas pirogênicas. Além disso, foi demonstrado que o composto 3Et-TFDP apresenta potencial antiinflamatório, atuando sobre o influxo de leucócitos, permeabilidade vascular peritoneal e aumento da atividade da MPO induzidos por S. cerevisiae. Em conjunto, nossos dados sugerem que os derivados pirazolínicos 3Et- e 3Pr-TFDP parecem ser compostos antipiréticos e antiinflamatórios promissores. / Fever is a regulated increase of body core temperature characterized by a raised thermoregulatory set point, which results from the interaction of the central nervous and immune systems. While fever is a hallmark of injury, infection and inflammation, it has also been considered the most important component of acute-phase response. Although there is evidence supporting the idea that fever enhances host defenses, some studies have suggested that raising core temperature to the febrile range may be harmful. Therefore, in the clinical situations in which fever-associated risks outweigh benefits, antipyretic treatment is formally indicated. Pyrazoles constitute an important group of organic compounds that have been extensively studied due to their numerous biological activities. Recently a series of pyrazole derivatives have been screened for antinociceptive and antiedematogenic activity in mice. These compounds cause antinociception in the formalin test and in the Freund's adjuvant (CFA) animal model of arthritis and decrease carrageenin-induced edema. Given the effects reported for these compounds, we decided to investigate the effect of eight 5-hydroxy-5-trifluoromethyl-4,5-dihydro- 1H-1-carboxyamidepyrazoles (TFDPs) on body temperature, baker´s yeast-induced fever and peritoneal inflammation in 28 days-old male Wistar rats. Only 3ethyl- and 3propyl-TFDP (140 and 200 μmol/kg, respectively, s.c., 4 h after S. cerevisiae injection) attenuated baker’s yeastinduced fever by 61.0% and 82.4%, respectively. These two effective antipyretics were selected to investigate the mechanisms of action. The effects on cyclooxygenase-1 and -2 (COX-1 and COX-2) activities, on 1,1-diphenyl-2-picrylhydrazyl (DPPH) oxidation in vitro, on TNF-a and IL- 1b levels and on leukocyte counts in the washes of peritoneal cavities of rats injected with baker’s yeast were determined. While 3ethyl- and 3propyl-TFDP did not reduce baker’s yeastinduced increases of IL-1 or TNF- levels, 3ethyl-TFDP caused a 42% reduction in peritoneal leukocyte count. 3ethyl- and 3propyl-TFDP did not alter COX-1 and COX-2 activities in vitro, but presented antioxidant activity in the DPPH assay with an IC50 of 39.3 (25.0-62.0) mM and 162.9 (135.6-195.7) mM, respectively. In a other set of the experiments, we investigate the effect of 3- ethyl- and 3-propyl-5-hydroxy-5-trifluoromethyl-4,5-dihydro-1H-1-carboxyamidepyrazoles on S.cerevisiae-induced peritoneal inflammation in rats. Pre-treatment with 3ethyl-TFDP (140 μmol/kg, 5 mL/Kg) significantly prevented S.cerevisiae-induced increase in leukocyte influx, peritoneal vascular permeability and myeloperoxidase activity, but had no effect on TNF-a and IL-1b levels. On the other hand, 3propyl-TFDP (200 μmol/kg, 5 mL/Kg) had no effect on these inflammatory parameters. The current study describes two novel antipyretic pyrazole derivatives, whose mechanisms of action do not involve the classic inhibition of the COX pathway or pyrogenic cytokine release. In addition, it is shown that 3ethyl-TFDP presents antiinflammatory potential, since it reduces leukocyte influx, peritoneal vascular permeability and MPO activity. Taken together, our data suggest that the pyrazole derivatives 3ethyl- and 3propyl-TFDP seems a promising antipyretic and anti-inflammatory compounds.
32

Atividade analgésica, anti-inflamatóriae vasorelaxante de dois derivados pirazólicos: 5-[1-(4- fluorfenil)-1H-pirazol-4-IL]-2H-tetrazola(LQFM 020) e 5- [1-(2-fluorofenil)-1H-pirazol-4-IL]-2H-tetrazola (LQFM 039) / Analgesic, anti-inflammatory and vasorelaxant activity of the two pirazoles derivative: 5-[1-(4- fluorfenil)-1H-pirazol-4-IL]-2H-tetrazola(LQFM 020) and 5- [1-(2-fluorofenil)-1H-pirazol-4-IL]-2H-tetrazola (LQFM 039)

Oliveira, Lanussy Porfiro de 31 October 2014 (has links)
Submitted by Cláudia Bueno (claudiamoura18@gmail.com) on 2015-11-11T20:45:46Z No. of bitstreams: 2 Dissertação - Lanussy Porfiro de Oliveira - 2014.pdf: 1478536 bytes, checksum: 2646f221282c9b288ef2da403ef374d4 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-11-12T09:40:17Z (GMT) No. of bitstreams: 2 Dissertação - Lanussy Porfiro de Oliveira - 2014.pdf: 1478536 bytes, checksum: 2646f221282c9b288ef2da403ef374d4 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-11-12T09:40:17Z (GMT). No. of bitstreams: 2 Dissertação - Lanussy Porfiro de Oliveira - 2014.pdf: 1478536 bytes, checksum: 2646f221282c9b288ef2da403ef374d4 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2014-10-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Inflammation is a complex process that aims to protect the body eliminating the harmful agent and to promote tissue repair is characterized by classic signs: pain, heat, redness and swelling as a result of failure to resolve the inflammatory process may occur loss of function. Control of pain and inflammation leads to the search for new drugs both analgesic and antiinflammatory drugs with good efficacy to aid in the treatment of these deseases. The aim of this study was to evaluate the pharmacological effects of two pyrazole derivatives. In acute nociception tests LQFM 020 (9, 17.5 and 35 mg/kg) and LQFM 039 (17.5, 35 and 70 mg/kg) reduced the number of writhing dose dependent manner to 53, 48 and 35; and 57, 52, 42, respectively, while the control group the number of writhes was 88. In the formalin test this antinociceptive effect was confirmed by the reduction in time reactivity to pain in both test phases, the time in the control group was 78 and 72s in the first phase and 150 and 128s in the second phase, with LQFM for 020 and 039 LQFM in the first phase was to reduce 50 and 47s and the second phase to 97 and 74s respectively. In bending the tail the groups of mice treated with LQFM 020 and LQFM 039 test were not able to increase the latency to thermal stimulus demonstrated that the analgesic effect does not involve central mechanisms. Furthermore, the results of the enzymatic activity of cyclooxygenase (COX) and phospholipase (PLA2) in vitro tests indicated no part of the mechanism of action involved in the activity of these compounds. In vascular reactivity tests LQFM 020 promoted vasorelaxant effect presenting maximum effect (Emax) of 93% in aortic preparations with endothelium and maximum effect (Emax) of 91% without endothelium . LQFM 039 also promoted vasorelaxant effect with maximum effect (Emax) of 80% when tested in preparations with endothelium and maximum effect (Emax) of 76% without endothelium, given this result, we investigated the mechanism of action of these compounds. Our results showed that LQFM 020 and LQFM 039 demonstrated the involvement of NO/cGMP pathway and suggest also the involvement of sensitive Ca2+ channels in the plasma membrane voltage. / A inflamação é um processo complexo que tem como objetivo proteger o organismo, eliminando o agente lesivo, e promover a reparação tecidual sendo caracterizada por: dor, calor, rubor, edema e como consequência da não resolução do processo inflamatório pode ocorrer a perda da função. O controle da dor e inflamação leva a busca por novos fármacos tanto analgésicos quanto anti-inflamatórios com boa eficácia para auxiliar no tratamento destas doenças. O objetivo desse trabalho foi avaliar os efeitos farmacológicos de dois derivados pirazólicos. Nos testes de nocicepção aguda, LQFM 020 (9, 17,5 e 35 mg/kg) e LQFM 039 (17,5, 35 e 70 mg/kg), reduziram o número de contorções abdominais de maneira dose dependente para 53, 48 e 35 e para 57, 52 e 42, respectivamente, enquanto que no grupo controle o número de contorções foi de 88. No teste da formalina este efeito antinociceptivo foi confirmado com a redução no tempo de reatividade à dor nas duas fases do teste, o tempo no grupo controle foi de 78 e 72s na primeira fase e de 150 e 128s na segunda fase sendo que para LQFM 020 e LQFM 039 na primeira fase a redução foi para 50 e 47s e na segunda fase para 97 e 74s respectivamente. No teste de flexão de cauda os grupos de camundongos tratados com LQFM 020 e LQFM 039 não aumentaram a latência ao estímulo térmico demonstrando que o efeito analgésico não envolve mecanismos centrais. Os resultados dos testes de atividade enzimática de cicloxigenase (COX) e fosfolipase (PLA2) in vitro sugere que a inibição destas enzimas não faz parte do mecanismo de ação envolvido na atividade desses compostos. Nos testes de reatividade vascular LQFM 020 promoveu efeito vasorrelaxante apresentando efeito máximo (Emax) de 93% em preparações de aorta com endotélio e efeito máximo (Emax) de 91% sem o endotélio. LQFM 039 também promoveu efeito vasorrelaxante com efeito máximo (Emax) de 80% quando testadas em preparações com endotélio e efeito máximo (Emax) de 76% sem o endotélio, dado este resultado, foi investigado o mecanismo de ação desses compostos. Os resultados mostraram que LQFM 020 e 039 LQFM demonstram o envolvimento da via NO / GMPc e também sugerem o envolvimento de canais de Ca2+ sensíveis à voltagem na membrana plasmática.
33

Avaliação da toxicidade aguda e subaguda de um novo protótipo candidato a fármaco cardiovascular / Assessment of acute and subacute toxicity of a new cardiovascular drug candidate prototype

Moura, Soraia Santana de 28 November 2012 (has links)
Submitted by Erika Demachki (erikademachki@gmail.com) on 2017-03-16T21:37:33Z No. of bitstreams: 2 Dissertação - Soraia Santana de Moura - 2012.pdf: 3848911 bytes, checksum: 6c2c1f811c32328fc8cdb22d9edaf90a (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-03-20T13:38:54Z (GMT) No. of bitstreams: 2 Dissertação - Soraia Santana de Moura - 2012.pdf: 3848911 bytes, checksum: 6c2c1f811c32328fc8cdb22d9edaf90a (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-03-20T13:38:54Z (GMT). No. of bitstreams: 2 Dissertação - Soraia Santana de Moura - 2012.pdf: 3848911 bytes, checksum: 6c2c1f811c32328fc8cdb22d9edaf90a (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2012-11-28 / Fundação de Apoio à Pesquisa - FUNAPE / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Financiadora de Estudos e Projetos- Finep / Cardiovascular diseases are among the diseases of higher mortality rates in Brazil and worldwide . In contrast, it is reducing deaths of cardiovascular diseases due, in large part, to the production of drugs that can control their risk factors, but the wide reporting of side effects and contraindications persist and interfere negatively in the context of mortality these diseases. In this point, it is necessary to develop new drugs more effective and safer. The process of development of new drug requires numerous preclinical studies that generate information regarding safety profile in vivo determinants for making the decision to start clinical trials. Although it is a conventional practice, the use of animals in scientific research should happen consciously, always considering the ethical issues of animal experimentation. In this study, we investigated the basal cytotoxicity against 3T3 cells of seven pyrazole compounds (LQFM011, LQFM012, LQFM020, LQFM021, LQFM022, and LQFM023 LQFM024) and classified then in GHS system. Whereas the compound LQFM021 proved to be the most effective in the tests performed in parallel pharmacodynamic study, we investigated whether acute oral toxicity, subacute and mutagenicity of this compound. The results showed that the compounds have low cytotoxicity profile in basal cell line (3T3). The estimated LD50 values for compounds LQFM011, LQFM012, LQFM020, LQFM021, LQFM022, and LQFM023 LQFM024 were 548, 551, 568, 533, 457, 482, 565 mg / kg, respectively. The compounds LQFM020, LQFM023 LQFM024 were classified in category 5 GHS system and LQFM021 was classified in category 4. The subacute toxicological research for 28 days LQFM021 the compound showed that this compound did not affect the metabolic, hematological and biochemical animal parameters in any of the doses of exposure However, the histopathology indicated hepatotoxic and nephrotoxic potential of this compound and interference in the process of hematopoiesis, but did not indicate mutagenic potential. . Given the above, we conside / As doenças cardiovasculares estão entre as doenças de maior letalidade no Brasil e no mundo. Em contrapartida, vê-se um quadro redução das mortes atribuídas às enfermidades cardiovasculares devido, em grande parte, à produção de medicamentos capazes de controlar seus fatores de risco, porém, o vasto relato de efeitos colaterais e contraindicações persistem e interferem negativamente no quadro de morbimortalidade dessas doenças. Neste sentindo, é imprescindível buscar novos fármacos mais efetivos e seguros. O processo de desenvolvimento de um novo fármaco exige numerosos estudos pré-clínicos que geram informações quanto ao seu perfil de segurança in vivo, determinantes para a tomada de decisão de se iniciar os estudos clínicos. Embora seja uma prática convencional, o uso de animais em pesquisas científicas deve ocorrer de forma consciente, considerando sempre as questões éticas de experimentação animal. Neste trabalho, investigou-se a citotoxicidade basal frente as células 3T3 de sete compostos pirazolínicos (LQFM011, LQFM012, LQFM020, LQFM021, LQFM022, LQFM023 e LQFM024) e suas classificações no sistema GHS. Considerando que o composto LQFM021 demonstrou ser o mais eficaz nos ensaios realizados em paralelo de farmacodinâmica, investigou-se toxicidade oral aguda, subaguda e mutagenicidade do composto. Os resultados mostraram que os compostos possuem perfil de baixa citotoxicidade em linhagem basal (3T3). Os valores de DL50 estimados para os compostos LQFM011, LQFM012, LQFM020, LQFM021, LQFM022, LQFM023 e LQFM024 foram 548, 551, 568, 533, 457, 482, 565 mg/kg, respectivamente. Os compostos LQFM020, LQFM023 e LQFM024 foram classificadas na categoria 5 do sistema GHS e o composto LQFM021 foi classificado na categoria 4. A investigação toxicológica subaguda por 28 dias do composto LQFM021 mostrou que este composto não interferiu nos parâmetros metabólico, hematológico e bioquímico dos animais em nenhuma das doses de exposição. No entanto, o estudo histopatológico indicou potencial nefrotóxico e hepatotóxico deste composto e interferência sobre o processo de hematopoiese, entretanto, não apresentou potencial mutagênico. Diante do exposto, consideramos que o composto LQFM021 apresenta um baixo perfil de toxicidade e os estudos de continuidade devem ser encorajados.
34

From small molecules to nano-scale architectures - a supramolecular approach

Scott, Benjamin M. T. January 1900 (has links)
Doctor of Philosophy / Department of Chemistry / Christer B. Aakeroy / We have shown that supramolecular synthons can be used to construct discrete two or three component co-crystals and 1-D inorganic-organic chains and dramatically influence the arrangement of nanoparticle assemblies. A collection of supramolecular reagents (SR's) have been designed and synthesised to carry out a systematic study into hydrogen bonding. In order to test Etter's guideline "the best proton donor and acceptor remaining after intramolecular hydrogen-bond formation will form an intermolecular hydrogen-bond" and to develop a hierarchy of interactions, a series of co-crystals between the supramolecular reagents and hydrogen-bond donors (carboxylic acids) have been synthesised. Co-crystals with pyrazole benzamide SR's have demonstrated the ability to fine-tune hydrogen-bond formation. By utilising a poor hydrogen-bond acceptor (pyrazole) the incoming carboxylic acid opts to form a heteromeric acid-amide dimer via N-H[three dots]O hydrogen bonds. Additionally, we have shown that the hydrogen-bond acceptor strength of the pyrazole can be turned up through simple covalent modifications (i.e. isomer change or addition of methyl groups to the pyrazole ring). Although the heteromeric acid-amide dimer is observed, O-H[three dots]N hydrogen bonds to the pyrazole are also observed in cases when more than one donor site is present (i.e. di-carboxylic acids and 4-hydroxybenzoic acid). Furthermore, co-crystals with picolyl-indazole and pyrimidine-pyrazole SR's agree with Etter's guideline. In all cases, the incoming carboxylic acid forms an O-H[three dots]N hydrogen bond to the best acceptor (pyridine and pyrazole, respectively). The homomeric amide-amide dimer has been used to construct inorganic-organic hybrid materials. The reaction between the pyrazole benzamide ligands with acac or "paddle-wheel" complex ions yielded 1-D chains. Furthermore, pyrimidine-bispyrazole and functionalised 1,3-bisbenzylpyrazole ligands have been utilised as chelating-ligands for reliable metal coordination. Finally, the power of supramolecular synthons to control the arrangement of much larger nanoparticle assemblies has been shown. Both homomeric (acid-acid, alcohol-alcohol) and heteromeric (acid-imidazole, alcohol-imidazole) hydrogen bonding cause significant changes in nanoparticle assemblies.
35

Designing New Heterometallic [2 x 2] Grids using Pyrazolate-bridged Ligands

Wong, Joanne 24 October 2019 (has links)
No description available.
36

Synthese neuer tri- und hexadentater Stickstoffbasen für Eisen(II) Spin Crossover Komplexe / Synthesis of novel tri- and hexadentate nitrogen bases for Iron(II) Spin Crossover complexes

Heider, Silvio 29 August 2013 (has links) (PDF)
Die vorliegende Arbeit thematisiert Eisen(II)-Komplexe mit Spinübergangseigenschaften. Dafür wurden neue hexadentate Liganden auf Basis von N,N'-Bis(2,2'-bipyridin-6-ylmethyl)-2,2'-biphenylendiamin entwickelt. Die in Kapitel 3.1 vorgestellten Systeme variieren dabei in den jeweiligen Substituenten der 6,6‘-Positionen der Biphenyleinheit. Es wird der Einfluss dieser Gruppen auf die magnetischen Eigenschaften der resultierenden Komplexe gezeigt. Im darauffolgenden Kapitel 3.2 wird ein variiertes Ligandensystem vorgestellt, in welchem anstelle einfacher Substituenten Donorfunktionen eingeführt wurden, sodass ein symmetrischer dinuklearer Eisen(II)-Komplex zugänglich war. In diesem sind die beiden Spin Crossover (SCO) Zentren erstmalig durch eine Biphenyleinheit verbrückt. Die durchgeführten Untersuchungen geben Hinweise auf eine allostere Wechselwirkung. Weiterhin wurde der Ligand durch N-Methylierung in ein tertiäres Amin überführt und die entsprechenden Komplexe mit Fe(II), Co(II) und Zn(II) synthetisiert (Kapitel 3.3). Diese wurden strukturell und elektrochemisch untersucht und hinsichtlich ihrer Redoxeigenschaften und Magnetismus mit den Komplexen der sekundären Amine verglichen. Ebenfalls wurde das Grundgerüst des auf sekundären Aminen basierenden Liganden so variiert, dass der terminale Donor durch stickstoffhaltige Fünfringheterocyclen – anstelle von Pyridin – verkörpert wurde (Kapitel 3.4). So konnten Eisen(II)-SCO Komplexe erhalten werden, welche eine wesentlich niedrigere Übergangstemperatur aufwiesen und somit magnetische Untersuchungen im Festkörper sowie des Photomagnetismus ermöglichten. Schließlich wurden neue tridentate Amine (2-(6-R-Pyridin-2-yl)-1,10-phenanthrolin) und deren Eisen(II)-Komplexe synthetisiert (Kapitel 3.5). Für einige dieser Komplexe konnte bereits das Spin Crossover Verhalten in Lösung untersucht werden. / The present thesis addresses iron(II) complexes with spin transition properties. For this purpose new hexadentate ligands were developed on the basis of N,N’-bis(2,2’-bipyridine-6-ylmethyl)-2,2’-biphenylenediamine. The systems introduced in chapter 3.1 vary in respect to the substituents in the 6,6’-positions of the biphenyl unit. The influence of these varying moieties on the magnetic behavior of the resulting complexes is shown. In the following chapter 3.2 a tuned ligand system is introduced, in which the substituents are donor functions so that a symmetrical dinuclear iron(II) complex was feasible. In this the two Spin Crossover (SCO) centers are for the first time connected by a biphenyl core. The executed experiments give hints to an allosteric interaction in this dinuclear compound. Moreover the ligand was reacted by N-methylation yielding a tertiary amine and the corresponding complexes with Fe(II), Co(II) and Zn(II) were synthesized (chapter 3.3). Those were investigated structurally and electrochemically and were then compared with the complexes with secondary amines in respect to their redox and magnetic properties. The ligand motif based on secondary amines was also modified in a way that the terminal donor was represented by nitrogen based five-ring heterocycles instead of pyridine (chapter 3.4). So iron(II) SCO complexes were available which showed much lower thermal transition temperatures and thus magnetic investigations in the solid state as well as investigations on the photomagnetic properties became possible. Ultimately, novel tridentate amines (2-(6-R-pyridine-2-yl)-1,10-phenanthroline) and the corresponding iron(II) complexes were synthesized (chapter 3.5). For some of those complexes the spin transition could already be monitored in solution.
37

Synthesewege zu neuen Mehrkernkomplexen von Pyrazol-NHC-Hybridliganden mit Übergangsmetallen - mit Fokus auf Silber-Komplexe / Synthesis Routs for Multicore Complexes of Pyrazol-NHC-Hybridligands with Transition Metals - Focussing on Silver Complexes

Georgiou-Smith, Maria 15 November 2010 (has links)
No description available.
38

Synthèses concises de pyrazoles et pyridones diversement fonctionnalisées dans le but d'effectuer des réactions de couplages croisés sélectifs

Delaunay, Thierry 17 December 2010 (has links) (PDF)
Ce mémoire est subdivise en deux parties. La première partie concerne la synthèse de pyrazoles présentant un intérêt sur le plan agrochimique. En effet, le noyau pyrazole est présent dans de nombreux composes ayant des activités biologiques diverses et en particulier antifongique. Au cours de ce travail, nous avons développé diverses approches convergentes de pyrazoles diversement substitués au moyen de réactions de couplages croisés pallado-catalyses sélectifs et séquentiels à partir de pyrazoles possédant différents points d'encrages. Dans la deuxième partie, nous nous sommes intéressés à la synthèse de diverses furopyridones en tant qu'analogues de produits naturels possédant une activité antifongique, et notamment le Cladobotryal. Dans ce but, diverses alcynylpyridones ont été synthétisées et mises en jeu dans divers processus de cyclisation pour atteindre de manière divergente une série de furo[3,2-c]pyridin-4-ones, furo[3,2-c]pyridin-6-ones et furo[2,3-b]pyridin-4-ones
39

Influência dos parâmetros reacionais na N-alquilação de 3,5-dimetil-1h-pirazol sob irradiação de micro-ondas / Reaction parameters influence in the 3,5-dimethyl-1h-pyrazole N-alkylation under microwave irradiation

Trindade Filho, Jefferson 27 February 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work describes the reaction parameters influence in the 3,5-dimethyl-1H-pyrazole N-alkylation under microwave irradiation. The experiments were performed in different conditions with the purpose of verified the influence of temperature, basic, pressure, solvent effect and ionic liquid effect as passive heating elements (PHEs). The used alkylant agents were 1-butyl bromide, 2-butyl bromide, 1-ethyl iodide, 1-ethyl bromide and 1-butyl chloride. The ionic liquids [BMIM][BF4], [EMIM][BF4], [OMIM][BF4] and [BPy][BF4] were applied as PHEs. Initially, it was possible verified which elevated temperatures (100 - 150°C) allows to perform the reaction in very short reaction times (2,5 - 10 min). In general, it was observed which the base need is related to low reaction temperatures and alkylant agents of low reactivity. In addition, enhanced conversions were obtained with the solvent polarity and/or internal pressure increase. When different ionic liquids were used as PHEs, no relevant conversion difference was observed to the studied reaction. / Este trabalho descreve a influência dos parâmetros reacionais sobre a N-alquilação de 3,5-dimetil-1H-pirazol assistida por irradiação de micro-ondas. Os experimentos foram conduzidos em diferentes condições a fim de verificar a influência da temperatura, base, pressão, efeito do solvente e efeito do líquido iônico como elemento passível de aquecimento (EPA). Como agentes alquilantes, foram utilizados 1-bromobutano, 2-bromobutano, 1-iodoetano, 1-bromoetano e 1-clorobutano. Os líquidos iônicos [BMIM][BF4], [EMIM][BF4], [OMIM][BF4] e [BPy][BF4] foram utilizados como EPAs. Através dos experimentos realizados, foi possível verificar que elevadas temperaturas (100 - 150°C) permitem a utilização de curtos tempos reacionais (2,5 - 10 min). De modo geral, foi observado que a necessidade de base está relacionada a baixas temperaturas reacionais e agentes alquilantes de baixa reatividade. Além disso, melhores conversões foram obtidas com o aumento da polaridade do solvente e/ou da pressão interna do vaso reacional. Quando diferentes líquidos iônicos foram utilizados como EPAs, não foram observadas diferenças significativas de conversão para a reação estudada.
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Estudos estruturais e em química medicinal visando a identificação de novos inibidores da acetilcolinesterase Ipisox, Prisox, Ocisox, 4d, b07, 13b e c90 / Structural studies and in medicinal chemistry aiming at the identification of new inhibitors of acetylcholinesterase Ipisox, Prisox, Ocisox, 4d, b07, 13b and c90

Silva, Givanildo Santos da 25 February 2016 (has links)
This work presents a crystal chemistry study of seven compounds grouped into three classes: isoxazoles, pyrazoles and pyrazolines here called IPISOX, PRISOX, 4D, OCISOX, C90, B07 e 13B, in order to identify novel acetylcholinesterase inhibitors. The structures of the listed compounds were determined by X-ray diffraction method using monocrystalline samples of the aforementioned substances. The disagreement rates seen between the model and the model defined by the diffraction pattern were: 0.0708; 0.0399; 0.0513; 0.0562; 0.0726; 0.0519; 0.0457 to IPISOX, PRISOX, OCISOX, 4D, B07, 13B e C90, respectively. A appendix refers to several methods involved in the process of recrystallization was attached to work, since it received 13 of the 16 substances to study were improperly to be subjected to the technique of Xray diffraction. To obtain factors responsible for the stability of the lens system were carried Closed Layer Interactions Analysis (ICF). The average values of delocalized electron energies determined in kcal.mol-1 were: 19.00 (IPISOX) ; 23.00 (PRISOX) ; 12.00 (OCISOX and B07) ; 9.00 (4D) ; 6,00 (13B) and 5.00 (C90) . Such relocations are from electronic transitions of the type n * (donor receiver). Other electronic relocation of C-N *O-H and C-H *O-H were also observed for some compounds. However, the first mentioned are relevant to the stability of the electron lens packaging. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Este trabalho apresenta um estudo cristaloquímico de sete compostos agrupados em três classes: isoxazóis, pirazóis e pirazolinas aqui denominados de IPISOX, PRISOX, 4D, OCISOX, C90, B07 e 13B, no intuito de identificar novos inibidores da Acetilcolinesterase. As estruturas dos compostos mencionados foram determinadas por método de difração de Raios X usando amostras monocristalinas das substâncias mencionadas anteriormente. Os índices de discordância verificado entre o modelo proposto e o modelo definido pelo padrão de difração foram: 0,0708; 0,0399; 0,0513; 0,0562; 0,0726; 0,0519; 0,0457 para IPISOX, PRISOX, OCISOX, 4D, B07, 13B e C90, respectivamente. Um apêndice referente aos diversos métodos envolvidos no processo de recristalização foi anexado ao trabalho, uma vez que 13 das 16 substâncias recebidas para estudo estavam em forma inadequada para serem submetidas à técnica de difração de raios X. Visando obter fatores responsáveis pela estabilidade do sistema cristalino foram realizadas Análises de Interações de Camada Fechada (ICF). Os valores médios das energias de deslocalização eletrônica determinados, em kcal.mol-1, foram: 19,00 kcal.mol-1 (IPISOX); 23,00 (PRISOX); 12,00 (OCISOX E B07); 9,00 (4D); 6,00 (13B) E 5,00 (C90). Tais deslocalizações são oriundas de transições eletrônicas do tipo n * (doador receptor). Outras deslocalizações eletrônicas do tipo C-N *O-H e C-H *O-H também foram observadas para alguns compostos. No entanto, as primeiras mencionadas são relevantes para a estabilidade eletrônica do empacotamento cristalino.

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