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Adebayo, Francis Opeyemi. "Dietary habits and prevalence of obesity among type 2 diabetes patients seen at Scott Hospital, Morija, Lesotho." Thesis, University of Limpopo (Medunsa Campus), 2010. http://hdl.handle.net/10386/260.
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Thesis (M Med (Family Medicine))--University of Limpopo (Medunsa Campus), 2010.Introduction: Diabetes Mellitus still remains an important non- communicable disease globally. The burden of the disease continues to rise even in the sub-Saharan Africa. Aim: The study aimed to assess and describe the dietary practices and the prevalence of obesity among type 2 diabetic patients seen at Scott Hospital. Methods: A descriptive cross- sectional study was conducted among type 2 diabetic patients at Scott Hospital, Morija, Lesotho. A simple random sample of 50 participants was selected and each completed an interviewer administered questionnaire. The administration of the questionnaire was done by the researcher and a research assistant. Socio- demographic characteristics of the participants were obtained, anthropometric measurements were height and weight of each participant with subsequent determination of the BMI. Dietary intake was assessed using questions from a modified food frequency questionnaire of 16 food groups that reflect the commonest food items available. Results: The results showed that 86% (43/50) of the participants were females and 14% (7/50) were males with a female: male ratio of 6:1. The majority (72%) were above age 50 years and with regards to educational status, 62% had primary school education as the highest level attained. Four percent (4%) had no formal education. Fifty percent (50%) of the participants were unemployed. The mean weight of the participants was 84.22 ± 13.51 kg and the mean height was 157.76 ± 6.10 cm. The mean BMI was 33.97 ± 4.99 kg/m². Seventy-eight percent (38/50) of the participants were obese, and 14% (7/50) of the participants who were females, were morbidly obese with BMIs ≥ 40kg/m². The prevalence of obesity when stratified by gender showed that 57% (4/7) of male participants and 81% (35/43) of female participants were obese. According to the dietary assessments, food groups with the highest reported consumption per unit per month were; maize meals, breakfast-cereals and bread respectively. Conclusion: The study showed a predominantly female and elderly population of type 2 diabetics at Scott Hospital, Morija, Lesotho. The prevalence of obesity was high (78%) among the participants and this further supports the view that obesity is a major risk factor for type 2 diabetes. Reported dietary intake showed a higher consumption of carbohydrates and a very low intake of dietary fibre as represented by legumes. Keywords: Type 2 diabetes mellitus, dietary habits and obesity.
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Kemang, Leluma. "The role of Morija Arts and Cultural Festival as a mechanism for promoting tourism among local communities." Thesis, University of Zululand, 2012. http://hdl.handle.net/10530/1263.
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A dissertation submitted to the Faculty of Arts in partial fulfilment of the requirements for the Master Degree in Recreation and Tourism in the Department of Recreation and Tourism at the University of Zululand, South Africa, 2012.This research study was conducted with the view of investigating the Morija Arts and Cultural Festival as tourist attraction. Morija community has staged the event for more than ten (10) years. It was first held in 1999, but it seems that the event has not shown the great potential to the Morija communities. The broad intention of the study was to reveal the barriers and come up with a strategy, which would mobilise the potential of the cultural festival towards benefiting the local communities, tourists and other stakeholders. It is further the intention of this study to close the gaps which are existing in the management of the Morija Arts and Cultural Festival as tourist attraction in Lesotho.
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Holstein, Julian Victor Sebastian. "Morita cohomology." Thesis, University of Cambridge, 2014. https://www.repository.cam.ac.uk/handle/1810/245136.
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This work constructs and compares different kinds of categorified cohomology of a locally contractible topological space X. Fix a commutative ring k of characteristic 0 and also denote by k the differential graded category with a single object and endomorphisms k. In the Morita model structure k is weakly equivalent to the category of perfect chain complexes over k. We define and compute derived global sections of the constant presheaf k considered as a presheaf of dg-categories with the Morita model structure. If k is a field this is done by showing there exists a suitable local model structure on presheaves of dg-categories and explicitly sheafifying constant presheaves. We call this categorified Cech cohomology Morita cohomology and show that it can be computed as a homotopy limit over a good (hyper)cover of the space X. We then prove a strictification result for dg-categories and deduce that under mild assumptions on X Morita cohomology is equivalent to the category of homotopy locally constant sheaves of k-complexes on X. We also show categorified Cech cohomology is equivalent to a category of ∞-local systems, which can be interpreted as categorified singular cohomology. We define this category in terms of the cotensor action of simplicial sets on the category of dg-categories. We then show ∞-local systems are equivalent to the category of dg-representations of chains on the loop space of X and find an explicit method of computation if X is a CW complex. We conclude with a number of examples.
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Freitas, Vivianny Aparecida Queiroz. "Ação da curcumina e morina em leveduras do Complexo Cryptococcus neoformans." Universidade Federal de Goiás, 2017. http://repositorio.bc.ufg.br/tede/handle/tede/7402.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Cryptococcosis is a fungal disease caused by yeasts belonging to the complex Cryptococus neoformans. The antifungal arsenal available for the treatment of this disease is still restricted and is related to the high toxicity and side effects of some drugs, causing great harm to the patients. In this context, it is necessary to discover new bioactives to quell the infections and reduce the adverse effects. The plants have rich source of secondary bioactive metabolites such as tannins, terpenoids, saponins, alkaloids, flavonoids and other compounds, registered with expressive antimicrobial properties. Therefore, the research of natural compounds and derivatives of natural products has been relevant in recent years, due to their relevance in the discovery of new drugs, in addition to which the association of drugs or compounds with different mechanisms of action has been used as an alternative in conventional therapy. We evaluated the mechanisms of action and antifungal effect of natural compounds, curcumin and morin, on Cryptococcus neoformans and Cryptococcus gattii isolates. The antifungal activity was determined across the minimum inhibitory concentration (MIC) and minimum fungicide (MFC). Polyphenols showed MICs ranging from 2 to 256 μg/mL. The compounds showed a synergistic interaction in 30% (6/20) and 15% (3/20) of the isolates when dealing with morin and curcumin, respectively, associated with fluconazole. In the interaction with amphotericin B morin presented synergism in 70% (14/20) of the isolates. Both compounds did not exhibit antagonism in any of the combinations. Changes in fungal cell morphology were observed, and in contact with red blood cells, presented low toxicity. The mechanisms of action revealed that both polyphenols act on the membrane of the fungal cell, inhibiting the synthesis of ergosterol and causing damage to it. These results demonstrate the potential of the compounds as natural bioactives, with great impact on the discovery of new drugs and their efficacy to be used in the treatment of fungal infections.
A Criptococose é uma doença fúngica causada por leveduras pertencentes ao complexo Cryptococus neoformans. O arsenal antifúngico disponível para o tratamento dessa doença ainda é restrito e está relacionado à elevada toxicidade e efeitos colaterais de alguns fármacos, causando grande prejuízo aos pacientes Neste contexto, se faz necessário descobrir novos bioativos para debelar as infecções e reduzir os efeitos adversos. As plantas apresentam rica fonte de metabólitos secundários bioativos como taninos, terpenóides, saponinas, alcalóides, flavonoides e outros compostos, registrados com expressiva propriedade antimicrobiana. Portanto, a pesquisa de compostos naturais e derivados de produtos naturais tem sido pertinente nos últimos anos, devido à sua relevância na descoberta de novos medicamentos, além do que, a associação de fármacos ou compostos, com diferentes mecanismos de ação tem sido utilizada como alternativa na terapia convencional. Nós avaliamos os mecanismos de ação e o efeito antifúngico dos compostos naturais, curcumina e morina, sobre isolados de Cryptococcus neoformans e Cryptococcus gattii. A atividade antifúngica foi averiguada através da determinação da concentração inibitória mínima (CIM) e fungicida mínima (CFM). Os polifenóis, apresentaram CIMs que variaram de 2 a 256 μg/mL. Os compostos apresentaram interação sinérgica em 30% (6/20) e 15%(3/20) dos isolados se tratando da morina e curcumina, respectivamente, associada ao fluconazol. Na interação com a anfotericina B a morina apresentou sinergismo em 70% (14/20) dos isolados. Ambos os compostos não apresentaram antagonismo em nenhuma das combinações. Alterações na morfologia da célula fúngica foram observadas, e em contato com as hemácias, apresentaram baixa toxicidade. Os ensaios de mecanismos de ação revelaram que ambos os polifenóis atuam na membrana da célula fúngica inibindo a síntese de ergosterol e causando danos a mesma. Estes resultados demonstram o potencial dos compostos como bioativos naturais, apresentando grande impacto na descoberta de novos fármacos e sua eficácia para serem utilizados no tratamento de infecções fúngicas.
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Melo, Samara Su?nya Nogueira Serafim de. "Valor nutritivo de fenos de moringa (moringa oleifera lam) com diferentes idades de corte." Universidade Federal do Rio Grande do Norte, 2012. http://repositorio.ufrn.br:8080/jspui/handle/123456789/17185.
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Previous issue date: 2012-03-29This study was conducted to evaluate the consumption and digestibility of dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), total carbohydrates (TC), non-fiber carbohydrates (NFC) and neutral detergent fiber (NDF) in sheep fed hay moringa (Moringa oleifera Lam) obtained with four cutting ages (28, 35, 42 and 49 days). We used 20 females Morada Nova breed, with 20kg of live weight, distributed in a completely randomized design and maintained in metabolism cages. There was a negative linear effect of age of cutting on DM intake, with an estimated maximum consumption of 0.67 kg / day for the hay produced at 28 days of cutting. It was also observed linear behavior, with an estimated maximum consumption 172g/dia, 0.36 kg / day; 18g/dia, at 35, 42 and 49 days old, for CP, OM and EE, respectively. For NDF, quadratic effect was found with advancing maturity of the plant. The apparent digestibility of DM, CP, OM and TC linearly decreased with advancing age of cutting hay Moringa oleifera. It was concluded that the hay Moringa oleifera showed better nutritional value after 28 days of cutting
O presente trabalho foi conduzido com o objetivo de avaliar o consumo e as digestibilidades aparentes de mat?ria seca (MS), mat?ria org?nica (MO), prote?na bruta (PB), extrato et?reo (EE), carboidratos totais (CHOT), carboidratos n?o fibrosos (CNF) e fibra em detergente neutro (FDN) em ovinos alimentados com feno de moringa (Moringa oleifera Lam) obtido com quatro idades de corte (28, 35, 42 e 49 dias). Foram utilizadas 20 f?meas da ra?a Morada Nova, com 20 kg de peso vivo m?dio, distribu?das em um delineamento inteiramente casualizado e mantidas em gaiolas de metabolismo. Observouse efeito linear decrescente da idade de rebrota sobre o consumo de MS, estimando-se consumo m?ximo de 0,67 kg/dia para o feno elaborado aos 28 dias de corte. Tamb?m foi observada resposta linear decrescente, estimando-se consumos m?ximos de 172 g/dia; 0,36 kg/dia; 18 g/dia, aos 35; 42 e 49 dias de idade, para PB, MO e EE, respectivamente. Para FDN, encontrou-se efeito quadr?tico com o avan?o da maturidade da planta. As digestibilidades aparentes de MS, PB, MO e CHOT diminu?ram linearmente com o avan?o da idade de corte do feno de Moringa ole?fera. Concluiu-se que o feno de Moringa ole?fera apresentou melhor valor nutritivo aos 28 dias de corte
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Afara, Bassima. "Morita equivalence of semigroups." Thesis, Heriot-Watt University, 2012. http://hdl.handle.net/10399/2637.
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Morita equivalence is a general way of classifying structures by means of their actions that is weaker than isomorphism but at the same time useful. It arose first in the study of unital rings in the 1950’s [35] but has since been extended to many other kinds of strucures, including classes of non- unital rings. It was first applied to semigroup theory in the 1970’s in the work of Banaschewski [5] and Knauer [19] who independently determined when two monoids were Morita equivalent. However they were unable to extend their definition to arbitrary semigroups since Banaschewski showed that Morita equivalence reduced to isomorphism. It was not until the 1990’s that Talwar [40, 41] was able to find a good definition of Morita equivalence for a class of semigroups that included all monoids but also all regular semigroups: the class of semigroups with local units. Such a semigroup is one in which each element has a left and a right idempotent identity. Talwar’s work was not developed further until the twenty-first century when a variety of mathematicians including Funk, Laan, Lawson, M´arki and Steinberg started to develop the Morita theory of semigroups in detail [9, 20, 25, 39]. Our thesis takes as its starting point Lawson’s reinterpretation of Talwar’s work. The thesis consists of three chapters. An essential ingredient in Morita theory is the notion of an equivalence of categories. For this reason, Chapter 1 of this thesis reviews all the categorical definitions needed. In Chapter 2, we describe in detail the work of Banaschewski and Knauer on the Morita theory of monoids. These two chapters contain no new work. We begin Chapter 3 by explaining why the obvious way of defining the Morita equivalence of two semigroups does not work. We then describe Lawson’s approach to Talwar’s work. This provides the foundation for our thesis. Our new contributions to the theory are contained in Sections 3.2, 3.3 and 3.4 and are based on Rees matrix semigroups. Talwar showed that the classical Rees matrix theorem for completely simple semigroups could be regarded as a Morita theorem: a semigroup is Morita equivalent to a group if and only if it is completely simple if and only if it is isomorphic to a Rees matrix semigroup over a group. This raises the question of determining what role Rees matrix semigroups play in the Morita theory of semigroups with local units. We investigate three different problems based on this idea: Section 3.2 In this section, we try to provean exact generalisation of the Rees theorem. We are interested in the case where S is Morita equivalent to T if and only if S is isomorphic to some kind of Rees matrix semigroup over T. Section 3.3 In this section, we prove that S is Morita equivalent to T if and only if S is a locally isomorphic image of a special kind of Rees matrix semigroup over T. This result was first proved by Laan and M´arki [20] but we give a new proof that generalizes the classical proof of the Rees theorem. Section 3.4 Finally, we solve the following problem: given an inverse semi-group S find all inverse semigroups T which are Morita equivalent to S. Our solution uses special kinds of Rees matrix semigroups over S. In this section, we also describe those semigroups which are Morita equivalent to semigroups with commuting idempotents. This builds on early work by Khan and Lawson [17, 18].
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Merisi, Piercarlo. "Ring equivalences from Morita theory." Thesis, University of Exeter, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307287.
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Rhyner, Bruno. "Morita-Psychotherapie und Zen-Buddhismus /." Zürich : Völkermuseum der Universität Zürich, 1988. http://catalogue.bnf.fr/ark:/12148/cb35516087g.
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Segrt, Kruna. "Morita theory in enriched context." Nice, 2012. http://www.theses.fr/2012NICE4005.
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Nous développons une version homotopique de la théorie de Morita classique en utilisant la notion de monade forte. C’était Anders Kock qui a montré qu’une monade T dans une catégorie monoidale Σ est forte si et seulement si la monade T est enrichie. Nous montrons que cette correspondance entre force et enrichissement se traduit par un 2-isomorphisme de 2-catégories. Sous certaines conditions sur la monade T, nous montrons que la catégorie homotopique des T-algèbres est équivalente au sens de Quillen à la catégorie homotopique des modules sur le monoïde d’endomorphismes de la T-algèbre T (I) librement engendré par l’unité de Σ. Dans le cas particulier ou le Σ est la catégorie des Γ-espaces de Segal munie de la structure de modèle stable de Bousfield-Friedlander et T est la monade forte associée à une Γ-théorie bien pointée, nous retrouvons un théorème de Stefan Schwede, comme corollaire du théorème homotopique de MoritaWe develop a homotopy theoretical version of classical Morita theory using the notion of a strong monad. It was Anders Kock who proved that a monad T in a monoidal category Σ is strong if and only if T is enriched in Σ. We prove that this correspondence between strength and enrichment follows from a 2-isomorphism of 2-catgories. Under certain conditions on T, we prove that the category of T-algebras is Quillen equivalent to the category of modules over the endomorphism monoid of the T-algebra T (I) freely generated by the unit I of Σ. In the special case where Σ is the category of Γ-spaces equipped with Bousfield-Friedlander’s stable model structure and T is the strong monad associated to a well-pointed Γ-theory, we recover a theorem of Stefan Schwede, as an instance of a general homotopical Morita theorem
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Noeske, Felix. "Morita-Äquivalenzen in der algorithmischen Darstellungstheorie." kostenfrei, 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=977196240.
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Hinchcliffe, Victoria. "The filter dimension is morita invariant." Thesis, University of Sheffield, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.505562.
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Jansen, Stefan. "H-Äquivariante Morita-Äquivalenz und Deformationsquantisierung." [S.l. : s.n.], 2006.
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Fidélis, Michele Ribeiro. "Teorema de Morita para categoria derivada." Universidade Federal de Viçosa, 2013. http://locus.ufv.br/handle/123456789/4923.
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Previous issue date: 2013-07-26Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
In this work we present concepts and results of triangulated and derived categories. The main objective is to prove Rickard s theorem, also known as Morita s theorem for derived categories. As an application of this result we show that finiteness of finitistic dimension is invariant under derived equivalences, as it is proved in Finiteness of finitistic dimension is invariant under derived equivalences by Shengyong Pan and Changchang Xi.
Neste trabalho apresentamos conceitos e resultados de categorias trianguladas e derivadas. O principal objetivo é demonstrar o Teorema de Rickard, também conhecido como Teorema de Morita para categorias derivadas. Como aplicação deste resultado mostramos que a dimensão finítistica é preservada por equivalência derivada, conforme o artigo "Finiteness of finitistic dimension is invariant under derived equivalences" de Shengyong Pan e Changchang Xi.
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Chan, Ka-wing Patricia. "The therapeutic effects of residential morita therapy." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B29727704.
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Segrt, Ratkovic Kruna. "Théorie de Morita dans un contexte enrichi." Phd thesis, Université Nice Sophia Antipolis, 2012. http://tel.archives-ouvertes.fr/tel-00785301.
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Nous développons une version homotopique de la théorie de Morita classique en utilisant la notion de monade forte. C'était Anders Kock qui a montré qu'une monade T dans une catégorie monoidale E est forte si et seulement si la monade T est enrichie. Nous montrons que cette correspondance entre force et enrichissement se traduit par un 2-isomorphisme de 2-catégories. Sous certaines conditions sur la monade T, nous montrons que la catégorie homotopique des T-algèbre est équivalente au sens de Quillen à la catégorie homotopique des modules sur le monoïde d'endomorphismes de la T-algèbre T (I) librement engendré par l'unité I de E . Dans le cas particulier où E est la catégorie des Γ-espaces de Segal munie de la structure de modèle stable de Bousfi eld-Friedlander et T est la monade forte associée à une Γ-théorie bien pointée, nous retrouvons un théorème de Stefan Schwede, comme corollaire du théorème homotopique de Morita.
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Gomes, Juliana Cristina 1983. "Morita-Baylis-Hillman na síntese de antitumorais." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/250255.
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Orientador: Fernando Antônio Santos CoelhoDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química
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Resumo: O importante papel desempenhado pela aromatase na síntese de estrógenos qualificou essa enzima como alvo para o desenvolvimento de inibidores seletivos, que podem ser utilizados no tratamento do cancer de mama. Recentemente, pesquisadores descreveram o isolamento de uma diidrocumarina da planta brasileira conhecida popularmente como sempre-viva. Essa substância apresentou-se como um importante inibidor de aromatase, o que nos impulsionou a propor uma síntese total para essa substância natural. A síntese proposta envolve apenas 10 etapas reacionais sendo que sete etapas já foram concluídas. A segunda parte deste trabalho destina-se a preparação diastereosseletiva de derivados de tetraidro-1,8- naftiridinas 3,4- substituídas através de adutos de Morita-Baylis-Hillman. Esta classe de compostos tem atraído considerável atenção devido, principalmente, a presença do esqueleto estrutural [1,8]-naftiridínico estar presente em muitos compostos naturais e sintéticos, que exibem várias propriedades biológicas. A síntese de vários derivados de [1,8]-naftiridinas foi realizada através de uma metodologia fácil, eficiente e que envolve apenas 3 etapas, com rendimentos globais variando de 18- 60%. O método é baseado em uma sequência em cascata envolvendo uma reação de adição de Michael e uma reação de substituição nucleofílica aromática, na qual formam um ciclo e controlam a estereoquímica relativa dos dois centros em uma única etapa
Abstract: The important role played by aromatase in the synthesis of estrogen makes this enzyme an important therapeutic target for the development of new selective inhibitors to be used in the treatment of breast cancer. Recently, a dihydrisocumarine having a remarkable inhibitory effect against aromatase has been isolated from a brazilian plant popularly known as ¿sempre-viva¿. The biological activity of this new substance stimulated us to propose an appproach to the total synthesis of this natural compound. The initially proposed synthetic approach involves 10 steps. In this work seven steps have been performed. In the second part of this work we describe a new diastereoselective approach to the preparation of 3.4-substituted tetrahydro-1,8- naphthyridines from Morita-Baylis-Hillman adducts. This class of compounds has attracted considerable attention, mainly because the [1,8]-naphthyridyl skeleton is present in many natural and synthetic biologically active compounds. The syntheses of several [1,8]-naphthyridine derivatives were accomplished using a facile and efficient methodology, in 3 steps and overall yield ranging from 18-60%. The method is based on a cascade sequence involving a Michael addition reaction, followed by a nucleophilic aromatic substitution reaction. In a one single step, a new cycle is formed and the relative stereochemistry of the two asymmetric centers is controlled
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Quimica Organica
Mestre em Química
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Uggioni, Bruno Brogni. "Sobre produtos cruzados e equivalência de Morita." reponame:Repositório Institucional da UFSC, 2013. http://repositorio.ufsc.br/handle/123456789/103526.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Físicas e Matemáticas, Programa de Pós-Graduação em Matemática Pura e Aplicada, Florianópolis, 2013Made available in DSpace on 2013-07-16T21:07:35Z (GMT). No. of bitstreams: 1 316856.pdf: 554921 bytes, checksum: 95ab3e3185f35cd80e7801fe50cf1357 (MD5)
Nesse trabalho estudamos a teoria de equivalência de Morita-Rieffel para álgebra de operadores por uma perspectiva geral e a aplicamos para entender produtos cruzados para ações de grupos compactos em C*-álgebras. Nós apresentamos quatro formas diferentes para especificar um contexto de equivalência de Morita entre C*-álgebras e consideramos alguns exemplos conhecidos para ilustrá-la. A C*-álgebra produto cruzado A×?G proveniente de um sistema dinâmico (A,G,?) é definida como o completamento de Cc(G,A) com respeito a uma certa norma universal naturalmente associada ao sistema dinâmico. Mostramos que as representações do produto cruzado estão em correspondência biunívoca com as representações covariantes do sistema. A teoria de representações da $C^*$-álgebra produto cruzado caracateriza-a, à menos de isomorfismo, mas é geralmente difícil de calculá-la explicitamente. Nosso objetivo principal, nessa direção, é apresentar alguns teoremas de equivalência de Morita que nos permitirão entender produtos cruzados a menos de equivalência de Morita em casos especiais. Em particular, mostramos que o produto cruzado A×?G em que ? é ação de um grupo compacto G sobre uma C*-álgebra A é Morita equivalente à álgebra de ponto fixo AG se a ação for saturada. Aplicamos, após, esse contexto de equivalência de Morita para provar o Teorema Simétrico de Imprimitividade para ações saturadas de grupos compactos que relaciona, via uma equivalência de Morita, os produtos cruzados para ações comutativas de dois grupos compactos.
Abstract : In this work we study operator algebra Morita-Rieffel equivalence from a general perspective and apply it to the understanding of crossed products for actions of compact groups on C*-algebras. We present four different forms to specify a Morita equivalence context between C*-algebras and consider some standard examples to illustrate it. The crossed product C*-algebra A×?G attached to a dynamical system (A,G,?) is defined as the completion of Cc(G,A) with respect to a certain universal norm naturally associated to the dynamical system. The representations of the crossed product are shown to be in bijective correspondence with covariant representations of the system. The representation theory of the crossed product C*-algebra characterizes it up to isomorphism, but it is generally difficult to compute it explicitly. Our main goal is this direction is to present some Morita equivalence theorems that enable us to understand crossed products up to Morita equivalence in certain special cases. In particular we show that the crossed product A×?G for an action of a compact group G on a C*-algebra A is Morita equivalent to the fixed point algebra AG provided the action is saturated. We then apply this Morita equivalence context to prove the Symmetric Imprimitivity Theorem for saturated compact group actions which relates, via a Morita equivalence, the crossed products of commuting actions by two compact groups.
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Lee, Beomki. "[ME]morial." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/97267.
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Thesis: M. Arch., Massachusetts Institute of Technology, Department of Architecture, 2015.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 106-107).
Challenging an archetypal relationship between collective memory and a multitude of traditional memorials, "[ME]morial" presents a new concept in memorial architecture based on the reinterpretation of Freud's and Bergson's ideas of memory. [ME]morial emphasizes a new relationship between individual memory and the individual to offer a new way of experiencing memorial space. Contemporary architecture's focus on communal memory has led to the primacy of a single image or rendering. Thus memorial architecture tends to miss opportunities for deeper exploration and individualized experiences beyond simplistic representations of memorialized events or figures. This thesis project proposes a memorial architecture for victims of the 3.11 earthquake and tsunami in Sendai, Japan. Three spatially different [ME]morials are the starting point for this open-ended project. The goal of the project is to create a new relationship between individual memory and the individuals, such that each individual will have personalized experiences in each [ME]morial. [ME]morial will serve as a space not only for soothing victims' wounded hearts, but also for letting people memorialize their individual memories. The project seeks to challenge and extend traditional architectural definitions of memorial architecture.
by Beomki Lee.
M. Arch.
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Contreras, González Pilar. "Tercera mordida." Tesis, Universidad de Chile, 2010. http://repositorio.uchile.cl/handle/2250/101492.
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Liu, Yinghao. "Organocatalyzed Morita-Baylis-Hillman Reaction: Mechanism and Catalysis." Diss., lmu, 2011. http://nbn-resolving.de/urn:nbn:de:bvb:19-125470.
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Sato, Ayako. "Integrating Morita Therapy and Art Therapy: An Analysis." Antioch University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=antioch1300467795.
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Sequeiros, Víctor Agustín. "Non omnis moriar." Doctoral thesis, Universidad Nacional de Cuyo. Facultad de Filosofía y Letras, 2011. http://bdigital.uncu.edu.ar/9196.
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Heider, Andreas. "Two results from Morita theory of stable model categories." [S.l.] : [s.n.], 2007. http://deposit.ddb.de/cgi-bin/dokserv?idn=985718641.
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Rodrigues, Tiago da Costa Alves da Fontoura. "Rearranjo de Claisen em adutos de Morita-Baylis-Hillman." reponame:Repositório Institucional da UnB, 2014. http://repositorio.unb.br/handle/10482/16668.
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Dissertação (mestrado)—Universidade de Brasília, Instituto de Química, Programa de Pós-Graduação em Química, 2014.Submitted by Jaqueline Ferreira de Souza (jaquefs.braz@gmail.com) on 2014-10-24T14:32:40Z No. of bitstreams: 1 2014_TiagodaCostaAlvesdaFontouraRodrigues.pdf: 5982154 bytes, checksum: 2591cb155a1799aa137776d60300116d (MD5)
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O trabalho foi iniciado pela síntese de nove adutos de MBH, quatro deles com um fragmento estrutural alifático e cinco com substituintes aromáticos. Com os adutos formados, partiu-se para a reação de rearranjo, seguindo o procedimento experimental descrito por Srikrishna e colaboradores. Os adutos alifáticos apresentaram conversão e rendimentos elevados, porém a seletividade se mostrou baixa, 7:1 em favor do isômero E. Esta foi a seletividade mais alta obtida no caso dos alifáticos. Os adutos aromáticos resultaram em um aumento drástico na seletividade, sendo a menor delas de 17:1 a favor do isômero E. Foram sintetizadas três lactonas alquilidênicas, possibilitando a separação dos isômeros formados na etapa do rearranjo, o que contribuiu no estudo da quantificação dos isômeros obtidos.
The work started with the formation of nine MBH adducts, four of them with an aliphatic fragment, and the other five adducts with aromatic substituents. The following step was rearrangement, based on the experimental procedures described by Srikrishna and co workers. The aliphatic adducts showed high conversions and yields, but with low selectivity (the highest observed was 7:1) where the E isomer was the major one. The aromatic adducts presented a dramatic increase in the selectivity, 17:1 was the lowest selectivity observed for all the aromatic adducts, with the isomer E as the major one. Three lactones were synthesized, and the isomers were isolated, contributing to the quantification of the obtained isomers.
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Abermil, Nacim. "Organocatalyse asymétrique de la réaction d'aza-Morita-Baylis-Hillman." Paris 11, 2010. http://www.theses.fr/2010PA112184.
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Ce projet scientifique porte sur le développement d'une version organocatalysée énantiosélective de la réaction d'aza-Morita-Baylis-Hillman (aza-MBH). Tout d'abord, la synthèse de nouveaux organocatalyseurs bifonctionnels dérivés de la β-isocupréidine a été réalisée et a permis d'atteindre d'excellents excès énantiomériques dans le cas de l'acrylate de β-naphtyle. La présence d'une quantité catalytique de β-naphtol s'est révéle��e essentielle à l'efficacité de la transformation. Pour la première fois, l'utilisation d'imines aliphatiques a permis de conduire aux adduits de la réaction d'aza-MBH avec de très bonnes énantiosélectivités. Dans un deuxième temps, un phénomène d'énantiodivergence a été identifié dans le cas des alkylvinylcétones. L'inversion de l'induction asymétrique a lieu suivant la présence ou non de β-naphtol, espèce protique achirale. Par la suite, l'emploi d'α-amidosulfones a permis d'augmenter significativement l'efficacité mais également l'énantiosélectivité de la réaction d'aza-MBH dans le cas des imines aliphatiques. Enfin, dans le but d'essayer de mieux comprendre le processus réactionnel, une étude de modélisation moléculaire a été menée avec le docteur Élise TranThe aim of this study is the development of a highly enantioselective aza-Morita-Baylis-Hillman reaction catalyzed by β-isocupreidine derivatives. First, new bifunctional organocatalysts have been synthesized and efficiently applied to the aza-MBH transformation involving β-naphthyl acrylate. Indeed, high yields and enantioselectivities have been achieved and the presence of a catalytic amount of β-naphthol appears to be essential to the reaction success. Moreover, aliphatic imines have been converted with excellent stereocontrol for the first time. Next, it has been discovered that β-naphthol, an achiral protic additive, was able to invert the enantioselectivity of the aza-MBH transformation ln the case of alkylvinylketones. Then, the use of α-amidosulfones as imine surrogates allow to increase both efficiency and asymmetric induction of the aza-MBH reactio in the case of aliphatic imines. Finally, in order to try to better understand the transformation process, a molecular modelling study has been conducted with Dr Élise Tran
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Ardila, Rene. "Morita equivalence of W*-correspondences and their Hardy algebras." Diss., University of Iowa, 2017. https://ir.uiowa.edu/etd/5703.
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Muhly and Solel developed a notion of Morita equivalence for C*- correspondences, which they used to show that if two C*-correspondences E and F are Morita equivalent then their tensor algebras $\mathcal{T}_{+}(E)$ and $\mathcal{T}_{+}(F)$ are (strongly) Morita equivalent operator algebras. We give the weak* version of this result by considering (weak) Morita equivalence of W*-correspondences and employing Blecher and Kashyap's notion of Morita equivalence for dual operator algebras. More precisely, we show that weak Morita equivalence of W*-correspondences E and F implies weak Morita equivalence of their Hardy algebras $H^{\infty}(E)$ and $H^{\infty}(F)$.
We give special attention to W*-graph correspondences and show a number of results related to their Morita equivalence. We study how different representations of a W*-algebra give rise to Morita equivalent objects. For example, we show that if (E,A) is a W*-graph correspondence and we have two faithful normal representations $\sigma$ and $\tau$ of A, then the commutants of the induced representions $\sigma ^{\ms{F}(E)}(H^{\infty}(E))$ and $\tau ^{\ms{F}(E)}(H^{\infty}(E))$ are weakly Morita equivalent dual operator algebras.
We also develop a categorical approach to Morita equivalence of W*- correspondences. This involves building categories of covariant representations and studying the groups $Aut(\mathbb{D}({(E^{\sigma}})^*)$ and $Aut(H^{\infty}(E))$ (the automorphism groups of the unit ball of intertwiners and the Hardy algebra). In this regard, we advance the work of Muhly and Solel by showing new results about these groups, their matrix representation and their algebraic properties.
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Walker, Ruari. "On Morita equivalences between KLR algebras and VV algebras." Thesis, University of East Anglia, 2016. https://ueaeprints.uea.ac.uk/58559/.
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This thesis is investigative work into the properties of a recently defined family of graded algebras, which we call VV algebras. These algebras were defined by Varagnolo and Vasserot. We compare categories of modules over KLR algebras with categories of modules over VV algebras, establishing various Morita equivalences. Using these Morita equivalences we are able to prove several properties of certain classes of VV algebras such as affine cellularity and affine quasi-heredity. We also include a discussion about the problems encountered when trying to define finite-dimensional quotients of these algebras. Finally, in certain settings, we show how to define these quotients and explain how they relate to cyclotomic KLR algebras.
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Freire, Kristerson Reinaldo de Luna. "Síntese assimétrica de pirrolizidinonas e pirrolizidinas substituídas a partir da reação de Morita-Baylis-Hillman." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/250256.
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Orientador: Fernando Antônio Santos CoelhoTese (doutorado) - Universidade Estadual de Campinas, Instituto de Química
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Resumo: As glicosidases regulam uma grande variedade de processos biológicos, incluindo a catálise, degradação, e biossíntese de oligossacarídeos e glicoconjugados. Inibidores eficientes dessas enzimas podem ser aplicados para o tratamento de várias doenças ou disfunções metabólicas, tais como doenças do estoque lisossomal, diabetes, cancer, malária e infecções virais, incluindo influenza e HIV. Neste trabalho, descrevemos a primeira síntese total de pirrolizidinonas e pirrolizidinas poli-hidroxiladas, benzillideno- e benzil-pirrolizidinonas e pirrolizidinas a partir de adutos de Morita-Baylis-Hillman (MBH). A estratégia sintética inicia-se com a síntese do aldeído N-Boc-4-hidroxi-D-prolinal, em 3 etapas (82 %), a partir da 4-hidroxi-D-prolina comercial. De posse do aldeído, realizou-se a reação de MBH, produzindo praticamente um único diastereoisômero ( 95% e.e.), que sofreu uma etapa de remoção de um grupo funcional e ciclização, formando uma pirrolizidinona. Esta última foi utilizada em duas sequências distintas: a primeira, envolve uma etapa one pot de ozonólise e redução de carbonila com NaBH4, e outra etapa de redução da carbonila com alana (AlH3), para fornecer a pirrolizidina poli-hidroxilada, com um rendimento global de 24% em 4 etapas; a segunda, envolve a reação de arilação de Mizoroki- Heck, utilizando como catalisador o paladaciclo de Nájera, visando fornecer as benzilideno-pirrolizidinonas. Estas, por sua vez, foram reduzidas com hidrogênio sob paládio, para fornecer as benzil-pirrolizidinonas. Tanto as benzil- quanto as benzilideno-pirrolizidinonas foram reduzidas com AlH3 para fornecer as benzilideno e benzil-pirrolizidinas, em rendimentos globais que variaram de 4 % a 23 %, em 4 ou 5 etapas. Os estudos de cristalografia de raios X permitiram determinar a estereoquímica absoluta e relativa de três pirrolizidinonas. Estudos de 2D-NOESY foram realizados para a confirmação da estereoquímica relativa das pirrolizidinonas e pirrolizidinas
Abstract: Glycosidases regulate a wide variety of biological processes, including catalysis, degradation, and biosynthesis of oligosacharides and glycoconjugates. Efficient inhibitors of these enzymes may therefore be applied to the treatment of several diseases or metabolic dysfunctions, such as lysosomal storage diseases, diabetes, cancers, malaria and viral infections, including influenza and HIV. Here we describe the first approach towards the total synthesis of a polyhydroxylated pyrrolizidinones, pyrrolizidines, benzylidene- and benzyl-pyrrolizidinones and - pyrrolizidines from asymmetric Morita-Baylis-Hillman (MBH) adducts. The synthetic strategy starts with the synthesis of aldehyde N-Boc-4R-Hydroxy-D-prolinal in three steps (82 %), from commercial 4-Hydroxy-D-proline. The MBH reaction between N-Boc-4R-Hydroxy-D-prolinal and methyl acrylate furnished a single isomer ( 95% ee). The MBH adduct was deprotected and cyclized in acid medium to provide the pyrrolizidinone. From this molecule, we evaluated two paths: the first involves a one pot ozonolysis and reduction of the carbonyl group with NaBH4 and reduction of lactam group with alane (AlH3) to provide a poly-hydroxylated pyrrolizidine, in four steps and 24% overall yield; the second involves the Mizoroki-Heck arylation reaction, using the Najera fs palladacycle as catalyst, to provide the benzylidenepyrrolizidinones. These, in turn, were reduced with hydrogen under palladium, providing the benzyl-pyrrolizidinones. Both the benzyl- and benzylidenepyrrolizidinones were reduced with AlH3 to provide the benzylidene and benzylpyrrolizidines, from 4% to 23% overall yields, over 4 or 5 steps. X-ray crystallography studies allowed determining the absolute and relative stereochemistry of three pyrrolizidinones. 2D-NOESY studies were performed to confirm the stereochemistry of pyrrolizidinones and pyrrolizidines
Doutorado
Quimica Organica
Doutor em Ciências
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Yamakawa, Nathália Christina Gonçalves 1986. "Epilepsia e Morita-Baylis-Hillman : uma abordagem sintética para ceramidas antiepiléticas." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/250239.
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Orientador: Fernando Antonio Santos CoelhoDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química
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Resumo: A epilepsia é uma das principais doenças do sistema nervoso central, caracterizada por uma alteração na atividade elétrica do cérebro, que leva a perdas de memória e convulsões. Essa doença afeta cerca de 50 milhões de pessoas no mundo, que são discriminadas e isoladas da sociedade. Existem vários medicamentos que podem ser utilizados, no entanto, muitas vezes é necessário a administração de associações desses que apresentam severos efeitos colaterais. Esse quadro justifica a necessidade da busca por substâncias mais eficientes para o tratamento dessa doença. Em 2008, Ahmed e cols. isolaram da esponja marinha Negombata corticata duas ceramidas que apresentaram importante atividade anti-convulsiva. Assim, este trabalho teve por objetivo estabelecer uma estratégia sintética para a preparação do fragmento polar de tais ceramidas. A rota foi baseada em um aduto de Morita-Baylis-Hillman (MBH), obtido com elevada diastereosseletividade a partir de uma reação entre o aldeído de Garner e o acrilato de etila. Uma reação de ozonólise na dupla ligação do aduto de MBH fornece um a-cetoéster, cuja carbonila cetônica e reduzida conduzindo a um único produto. A proteção das hidroxilas, permitiu a confirmação da estereoquímica relativa através de análise por difração de raios-X, que também evidenciou a ocorrência de racemização na reação de MBH. O diol também foi utilizado na preparação de um aza-açúcar, potencial inibidor de glicosidase, sendo esta síntese em apenas 4 etapas com 32% de rendimento global. A fração apolar da ceramida foi sintetizada a partir de uma reação de Grignard, e a junção dos fragmentos pode ser realizada utilizando-se uma reação de Wittig. Desta maneira, foi descrita uma nova estratégia sintética que pode ser aplicada na preparação de diversos análogos das ceramidas, desenvolvendo um antiepiléptico mais potente
Abstract: Epilepsy is a chronic brain disorder that affects around 50 million people all over the world. It is characterized by recurrent seizures - which are physical reactions to sudden excessive electrical discharges in a group of brain cells. The discrimination and social stigma that surround epilepsy worldwide are often more difficult to overcome than the seizures themselves. Because of this fact and the economical impacts of the disease, the research for new biologically active compounds is still necessary. In 2008, Ahmed et al. isolated from the Red Sea sponge Negombata corticata two ceramides, which exhibit in vivo anticonvulsant activity. This work is focused on establishing of a synthetic sequence to prepare the polar fragment present in both ceramides. The strategy was based on a Morita-Baylis-Hillman reaction between a Garner¿s aldehyde and ethyl acrylate that provided a functionalized intermediate in good diastereoselectivity. The major diastereoisomer was employed as substrate in an ozonolysis reaction, followed by a stereoselective reduction that afforded 1,2-diol as a single isomer. The acetonide derived from this 1,2-diol allowed us to determine through X-Ray diffraction analysis the relative stereochemistry of this compound as being 1,2- anti. To finish the synthesis of the polar fragment, the ester group present in the acetonide was reduced to the corresponding aldehyde. The diol also was applied in a high diastereoselective preparation of an azasugar in 4 steps and 32% yield overall. In this work we also describe the synthesis of a carbon chain of the ceramide, our route includes an approach to the apolar fragment obtained by a Grignard reaction; then a Wittig reaction can couple both fragments toward the finalization of the sphingosine¿s synthesis. Our synthetic route can also be used in the preparation of several analogues of the antiepiletic ceramides
Mestrado
Quimica Organica
Mestre em Química
30
Teodoro, Bruno Vinicius Motta 1985. "Síntese de núcleos indolizidínicos a partir de adutos de Morita-Baylis-Hillman. Avaliação de uma metodologia para a dessimetrização de adutos de Morita-Baylis-Hillman." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/250238.
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Orientador: Fernando Antonio Santos CoelhoDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química
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Resumo: Esta dissertação de mestrado está dividida em duas partes. Na primeira parte descrevemos os resultados obtidos na síntese de núcleos indolizidínicos, a partir de adutos de Morita-Baylis-Hillman (MBH). Na segunda parte, descrevemos os resultados obtidos na avaliação de uma reação de dessimetrização de adutos de MBH. Os núcleos indolizidínicos representam um padrão estrutural de grande interesse sintético, pois existem inúmeros alcaloides, com atividade biológica pronunciada, que contêm este núcleo. A metodologia desenvolvida nesse trabalho permite a preparação de núcleos indolizidínicos, a partir de adutos de MBH, em duas etapas. Assim, uma reação de ciclização intramolecular de um aduto, gera indolizinas que, após uma reação de hidrogenação total, conduz as indolizidinas. A rota desenvolvida é rápida, simples, eficiente e estereosseletiva. Os rendimentos globais variaram de 43 a 55%. Os excessos diastereoisoméricos obtidos variaram entre 68 e 86%, em favor do isômero cis. Nesta parte do trabalho avaliamos também um procedimento para preparar tetraidroindolizinas, a partir da hidrogenação parcial das indolizinas. Usando a mesma estratégia, descrevemos a preparação de tetraidroindolizinas com rendimentos que variaram entre 40-93%. Na segunda parte desse trabalho avaliamos uma alternativa de dessimetrização de adutos de MBH. A redução de ?-ceto-?-metileno-ésteres, obtidos a partir de uma reação de oxidação de adutos de MBH racêmicos, nos permite acessar a esses adutos em suas formas enantiomericamente puras. Após realizar uma triagem de catalisadores de redução assimétrica, a melhor condição encontrada nos forneceu o aduto de MBH enantioenrriquecidos, com um rendimento de 25% e um excesso enantiomérico de 68%, utilizando o catalisador CBS. A partir deste dado, outros estudos poderão ser realizados visando verificar a generalidade do método desenvolvido
Abstract: This work is divided in two parts. In the first part, we described the development of a strategy for preparing indolizidine skeletons starting from Morita-Baylis-Hillman (MBH) adducts. In the second part, the preliminary results of study for the desymmetrization of MBH adducts is reported. The indolizidine core is a structural pattern of great synthetic interest since it's present in the structure of several alkaloids with remarkable biological activity. The two-step methodology developed in this work allowed the efficient preparation of indolizidine nucleus from MBH adducts. Thus, an intramolecular cyclization reaction of MBH adducts derived from 2-pyridine-carboxaldehyde followed by platinum mediated hydrogenation affords the indolizidines in good overall yield. The developed methodology is simple, fast and stereoselective. The overall yields ranged from 43 and 55% and the diastereoisomeric excesses obtained ranged from 68 to 86%, in favor of the cis isomer. The partial hydrogenation of the indolizines allowed the preparation of tetrahydroindolizines. Thus, using the same strategy, we also described the preparation of tetrahydroindolizines with yields ranging from 40-93 %. In the second part of this work we described the preliminary results of an evaluation of an alternative desymmetrization strategy of MBH adducts. The reduction of ?-keto-?-methylene esters obtained from an oxidation of racemic MBH adducts could allow us to access these adducts in their enantiomerically pure forms. A screening of asymmetric reduction catalysts showed us that the CBS catalyst provided the best condition. An enantioenriched MBH adduct was obtained in 25% yield and 68% enantiomeric excess. This result will stimulate new studies in order to check the scope of this method
Mestrado
Quimica Organica
Mestre em Química
31
ALMEIDA, Milena Calado da Silva. "Aspectos da reprodução e alimentação da moréia-pintada, Gymnothorax moringa (Nelson, 2006), capturada no litoral norte do estado de Pernambuco." Universidade Federal Rural de Pernambuco, 2015. http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/7099.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
The spotted moray, Gymnothorax moringa, Muraenidae family, is an important species of marine fish, abundant in coral reefs, rocky bottoms and even in sandy areas covered with vegetation. It is very common in the Tropical Atlantic where it occurs along its western border, From North Carolina and Bermuda, to the southeast coats of Brazil. In the present work, the feeding habits of the species were studied, by means of its diet composition. With this objective, 403 stomachs were analyzed, of which only 126 (24.3%) had contents. Only seven food items were identified, all of them teleosts. The index of relative importance (IIR) was used to identify the order of importance of each item. The prey item with the highest IIR was the goatfish, Pseudopeneus maculatus, followed by other teleosts. The repletion index (empty ¼ filled ² / 4 filled and filled) was also determined, whereby 74.6% of the stomachs were empty, 8.5% ¼ filled, 3.1% ½ filled, and 12.7% were full. There was no stomach 3/4 filled. For the study of their reproductive biology, 416 specimens, caught from January 2013 to December 2014, were analyzed. It was possible to identify the sex of 370 individuals: 183 males, with a total length (CT) ranging from 47 cm to 109 cm (mean 73.8 cm) and 187 females, with CT between 47 cm and 97 cm (mean 70.0 cm). The average fertility was 30.332 oocytes. The monthly mean gonosomatic index (IGS) and the distribution of maturation stages suggest a higher reproductive activity for the species in Pernambuco coast, during summer months, between October and January.
A moréia-pintada, Gymnothorax moringa, pertencente à família Muraenidae, é uma importante espécie de peixe ósseo marinho, sendo abundante em fundos de coral, rochas e até mesmo em áreas arenosas com cobertura de vegetação. É muito comum no Atlântico Tropical onde ocorre, em sua margem ocidental, desde a Carolina do Norte e Bermudas, até o sudeste do Brasil. No presente trabalho, os aspectos alimentares da espécie foram estudados através da composição da sua dieta. Foram analisados 403 estômagos, dos quais apenas 126 (24,3%) apresentavam algum conteúdo. Foram identificados 7 itens alimentares, todos teleósteos, tendo sido utilizado o índice de importância relativa (IIR) para se estabelecer a ordem de importância de cada item. A presa com maior IIR foi o saramonete, Pseudopeneus maculatus, seguido de outos teleósteos. Também foi determinado o índice de repleção (vazio, ¼ preenchido, ½ preenchido, 3/4 preenchido e cheio), segundo o qual 74,6% dos estômagos encontravam-se vazios, 8,5% ¼ preenchidos, 3,1% ²/4 preenchidos e 12,7% encontravam-se cheios. Não houve estômagos com 3/4 preenchidos. Para o estudo de biologia reprodutiva, foram analisados 416 exemplares de moréia-pintada, capturados no período de janeiro de 2013 a dezembro de 2014, tendo sido possível a identificação do sexo de 370 indivíduos: 183 machos, com comprimento total (CT), variando entre 47 cm e 109 cm (média de 73,8 cm), e 187 fêmeas, com CT entre 47 cm e 97 cm, (média de 70,0 cm). A fecundidade media foi igual a 30.332 ovócitos. Os dados de variação mensal do IGS e dos estágios de maturação sugerem uma maior atividade reprodutiva para a espécie na costa pernambucana, nos meses de verão, entre outubro e janeiro.
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Hénaff, Marie Grovel Olivier. "Le noni (Morinda citrifolia)." [S.l.] : [s.n.], 2009. http://castore.univ-nantes.fr/castore/GetOAIRef?idDoc=56401.
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Oliveira, Neto Mario Cysneiros de. "A morada do artista." Universidade Católica de Pernambuco, 2018. http://tede2.unicap.br:8080/handle/tede/989.
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In this dissertation we have realized a reflective study over some of the reasons for the existence of the creative impulse and of Art. We had as a general goal to investigate the motivations for production and appreciation of art through theories of psychanalyses, philosophy and immersion in the artistic universe of Francisco Brennand. From psychanalyses, we’ve studied the concepts of pulsion, phantasy and sublimation in Sigmund Freud, the bond between sexuality and regression to the motherly womb in Sándor Ferenczi and the theory of creativity of Donald Woods Winnicott. From philosophy, we’ve used the concept of will from Arthur Schopenhauer, the subjective experience of spaces in the theory of Gaston Bachelard and the transcendence phenomena under the prism of Plato. Concerning the field research, we’ve investigated the creative aspects of Francisco Brennand and his relations with his atelier through personal contact and an interview with the artist, visits to the Oficina Brennand and access to the artistic and bibliographical collection of the place, as well as through texts and videos published in the media. Having collected the data, we’ve stablished connections between his artistic production with the theories studied and we’ve developed some thought and intuitions. We’ve oriented the research from dimensions, three spaces, the intrapsychic, intersubjective and transcendence, and to facilitate the understanding of our purpose we’ve created a metaphorical image, The Tree of Existence, which, respecting this tripartition, organizes our theoretical writings and offers a general view of the existing dynamics between the dimensions. We’ve considered the presence of a feeling of existential discomfort due to the interaction between those dimensions, and the existence of a conflict of opposing forces, each plane seeking to impose itself over the other and be dominant. Then we followed the guiding hypothesis that through the fruition of art, its creation and contemplation, there would be a reduction in the feeling of discomfort, and that this decrease would happen through two main experiences, two phenomena, the existential increase due to the achievement of metaphysical planes and the movement of return to a mythical past of fusion and completeness – the fire. This fact showed resemblances between the path and destiny of sexuality and art, sex and the divine, chaos and the superior world. The present text sought to explore some of these purposes and their means of realization.
Realizamos nesta dissertação um estudo reflexivo sobre algumas razões da existência do impulso criativo e da Arte. Tivemos como objetivo geral investigar as motivações da produção e apreciação da arte através de teorias da psicanálise, filosofia e imersão no universo artístico de Francisco Brennand. Da psicanálise, estudamos os conceitos pulsão, fantasia e sublimação em Sigmund Freud, o vínculo entre sexualidade e regressão ao útero materno em Sándor Ferenczi e a teoria da criatividade de Donald Woods Winnicott. Da filosofia, utilizamos o conceito de vontade de Arthur Schopenhauer, a vivência subjetiva dos espaços na teoria de Gaston Bachelard e os fenômenos da transcendência sob o prisma de Platão. Sobre a pesquisa de campo, investigamos os aspectos criativos de Francisco Brennand e sua relação com seu atelier a partir do contato pessoal e entrevista com o artista, por meio de visitas à Oficina Brennand e acesso ao acervo artístico e bibliográfico do local, por textos e vídeos publicados na mídia. Colhidos os dados, estabelecemos conexões entre sua produção artística com as teorias estudadas e desenvolvemos algumas intuições e reflexões. Orientamos a pesquisa a partir de dimensões, três espaços, o intrapsíquico, intersubjetivo e transcendência, e para facilitar o entendimento de nosso propósito criamos uma imagem metafórica, A Árvore da existência, que, respeitando essa tripartição, organiza nosso escrito teórico e oferta um panorama geral da dinâmica entre as dimensões. Consideramos a presença de um sentimento de mal-estar existencial decorrente da interação entre tais dimensões, por existir um conflito de forças opostas, cada plano buscando se impor aos demais e ser predominante. Então seguimos a hipótese norteadora de que pela fruição da arte, sua criação e contemplação, haveria a diminuição do mal-estar; e que tal minoração de desconforto ocorreria a partir de duas experiências principais, dois fenômenos, a ampliação existencial com alcance de planos metafísicos e o movimento de retorno a um passado mítico de fusão e completude – o fogo. Tal fato demonstrou semelhanças entre os caminhos e destinos da sexualidade e arte, o sexo e o divino, o caos e o mundo superior. E o presente texto buscou explorar alguns desses propósitos e suas vias de realização.
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Jara, Jo Patricia Milagros. "Mordida cruzada anterior dental." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2009. https://hdl.handle.net/20.500.12672/14751.
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El documento digital no refiere asesorSeñala que una de las funciones más importantes que le incumben al odontopediatra, es guiar el crecimiento y desarrollo de la dentición del niño a fin de diagnosticar, prevenir y tratar el desarrollo de maloclusiones o alteraciones dentarias, funcionales o esqueléticas. Las maloclusiones según la Organización Mundial de la Salud – OMS, ocupan el tercer lugar como problema de Salud Bucal y la mordida cruzada dental es una maloclusión de etiología múltiple. La mordida cruzada anterior dental ocurre cuando los incisivos maxilares ocluyen por lingual de los incisivos mandibulares, es generalmente observada en la dentición mixta y existe un acuerdo universal que esta condición deberá ser tratada tempranamente. Esto puede envolver uno o más dientes anteriores, tanto en la dentición primaria o permanente, cuando no está comprometido el aspecto esquelético los pacientes presentarán una relación normal antero-posterior con una relación de Angle clase I, así como, relación una céntrica y máxima intercuspidación coincidentes. El daño potencial en la dentición permanente si la mordida cruzada anterior no es tratada, es considerable; este puede ir desde una pérdida del hueso alveolar, migración apical del ligamento periodontal, daño o pérdida de los dientes anteriores hasta disturbios en la articulación temporomandibular. Hay varios tipos de mordidas cruzadas anteriores. Se ha propuesto una variedad de tratamientos, corona de acero invertida, bajalengua, plano fijo de acrílico, plano inclinado inferior de resina, aparatología removible con retenedores. El tratamiento temprano de esta maloclusión puede evitar desvíos del crecimiento. El manejo adecuado depende del diagnóstico correcto y tiempo de inicio del tratamiento.
Trabajo académico
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Kitulagoda, James E. "Further Studies of an Aza-Morita-Baylis Hillman-type Reaction." Thesis, University of Bristol, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.526012.
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Heesing, Christian [Verfasser]. "Einfluss der Dzyaloshinskii-Moriya-Wechselwirkung auf magnetische Moleküle / Christian Heesing." Bielefeld : Universitätsbibliothek Bielefeld, 2016. http://d-nb.info/110169419X/34.
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Mocquet, CeÌcile Magaly. "New bifunctional catalysts for the asymmetric Morita-Baylis-Hillman reaction." Thesis, University of Leeds, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.418232.
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Gomes, Juliana Cristina 1983. "Novos catalisadores bifuncionais para a reação de Morita-Baylis-Hillman." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/250245.
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Orientador: Fernando Antonio Santos CoelhoTese (doutorado) - Universidade Estadual de Campinas, Instituto de Química
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Resumo: A reação de Morita-Baylis-Hillman (MBH) é um método atrativo para a formação de ligação carbono-carbono. Esta transformação tem atraído a atenção devido ao fato dela ser seletiva (quimio-, régio-, diastereo-, e enantio-) e ser também um método com alta economia de átomos, convertendo substratos simples em produtos poli-funcionalizados de grande versatilidade sintética. Entretanto, apesar de suas inúmeras vantagens, essa reação possui vários inconvenientes tais como baixas velocidades, rendimentos moderados, alta concentração de catalisador nucleofílico e o uso de solventes orgânicos, o que dificulta a sua utilização industrial. Dessa maneira, fica claro a necessidade da busca de novos catalisadores e metodologias eficientes, tanto em termos de rendimentos, velocidades reacionais, quanto em termos de versatilidade, para que se possa ser aplicada a uma ampla variedade de substratos. Neste trabalho foi demonstrado o uso de um novo catalisador, um álcool derivado imidazólico bicíclico, para reações de MBH com enonas cíclicas. Esse novo catalisador funcionou eficientemente em um protocolo ecologicamente amigável, no qual as reações de MBH procederam em meio aquoso e com uma quantidade catalítica de dodecil sulfato de sódio (SDS), sem a necessidade de co-solventes orgânicos. Além disso, foi demonstrado que esse álcool imidazólico bicíclico é o único catalisador para reações de MBH aquosas entre isatinas não protegidas e enonas cíclicas, fornecendo núcleos 3-hidroxi-2-oxoindóis substituídos. Esse catalisador também pôde ser resolvido e aplicado na versão assimétrica dessa reação. E outros derivados imidazólicos foram sintetizados e também testados em MBH
Abstract: The Morita-Baylis-Hillman reaction is an attractive method for the construction of carbon_carbon bonds. This transformation has attracted attention due to the fact that it is selective (chemo, regio-, diastereomeric and enantiomeric) and also a method with high atom economy, converting simple substrates in poly-functionalized products of great synthetic versatility. Despite its interesting benefits, the MBH reaction suffers from several drawbacks, such as low reaction rates, moderate yields, high concentration of the nucleophilic catalyst, poor reactivities of ?-substituted activated olefins and of cyclic enones, and use of hazardous organic solvents, that have hampered its industrial utilization. Thus, it is clear the need to search for new catalysts and efficient methodologies, both in terms of yields, reaction speeds, and in terms of versatility, so that it can be applied to a wide variety of substrates. This work demonstrated the use of a new catalyst, an alcohol bicyclic imidazole derivative, for reactions with cyclic enones MBH. Thus, it is clear the necessity of finding new catalysts and efficient methodologies, both in terms of yields, reaction speeds, and in terms of versatility, so that it can be applied to a wide variety of substrates. This work demonstrated the use of a new catalyst, an alcohol bicyclic imidazole derivative, for reactions with cyclic enones MBH. This new catalyst worked effectively in ecofriendly conditions, where the MBH reactions proceeded in an aqueous medium with a catalytic amount of sodium dodecyl sulfate (SDS), without organic co-solvents. Furthermore, it was shown the imidazole bicyclic alcohol is the only catalyst for MBH aqueous reactions between isatins unprotected and cyclic enones, providing cores 3-hydroxy-2-substituted oxoindóis. This catalyst could also be resolved and applied to the asymmetric version of this reaction. And other imidazole derivatives were synthesized and also tested in MBH
Doutorado
Quimica Organica
Doutora em Ciências
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Mciteka, Lulama Patrick. "Novel applications of Morita-Baylis-Hillman methodology in organic synthesis." Thesis, Rhodes University, 2013. http://hdl.handle.net/10962/d1007598.
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The overall approach in the present investigation has been to explore applications of the Morita-Baylis-Hillman (MBH) reaction in asymmetric synthesis and in the continuation of systems with medicinal potential. To this end, a series of varied camphor-derived acrylate esters was prepared to serve as chiral substrates in asymmetric Morita-Baylis- Hillman reactions. Reduction of N-substituted camphor-10-sulfonamides afforded the 3- exo-hydroxy derivatives as the major products. Acylation of the corresponding sodium alkoxides gave the desired 3-exo-acrylate esters, isolation of which was complicated by concomitant formation of hydrochlorinated and diastereomeric competition products. Bulky camphorsulfonamides containing alkyl, dialkyl, aromatic and adamantyl groups were selected as N-substituents with the view of achieving stereoselective outcome in subsequent MBH reactions. The synthesis of novel camphor-derived Morita-Baylis-Hillman adducts using various pyridine-carboxaldehydes proceeded with exceptionally high yields with diastereoselectivities ranging from 7-33 % d.e. Both 1D and 2D NMR and HRMS techniques were employed to confirm the structures and an extensive study of the electropositive fragmentation patterns of a number of camphor-derived chiral acrylate esters was conducted. Attention has also been given to the application of MBH methodology in the construction of heterocyclic ‘cinnamate-like’ AZT conjugates which were designed to serve as dualaction HIV-1 integrase-reverse transcriptase (IN-RT) inhibitors. A number of pyridine carboxaldehyde-derived MBH adducts were synthesized using methyl, ethyl and t-butyl acrylates in the presence of 3-hydroxyquinuclidine (3-HQ) as catalyst. The yields for these reactions were excellent. The resulting MBH adducts were acetylated and subjected to aza-Michael addition using propargylamine. The resulting alkylamino compounds were then used in ‘Click reactions’ to form the targeted AZT-conjugates in moderate to excellent yield. In silico docking of computer modelled AZT-conjugates into the HIV-1 integrase and reverse transcriptase enzyme-active sites and potential hydrogen-bonding interaction with active-site amino acid residues were identified. The electrospray MS fragmentations of the AZT and the novel AZT-conjugates were also investigated and common fragmentation pathways were identified.
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Marquez, Adrian Vazquez. "Universal constructions for monads on internal categories and Morita contexts." Thesis, Swansea University, 2010. https://cronfa.swan.ac.uk/Record/cronfa42890.
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Donahue, Patricia A. "Efficacy study of brief Morita therapy intervention with shy adolescents." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/28035.
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The study examines the change effect of brief Morita counseling, based on Morita therapy, as an intervention with shy adolescent females (n = 12). The design used was a multiple-baseline across subjects with a time lag for treatment intervention. Subjects were selected from the mainstream student body at a Vancouver secondary school following screening with the Cheek and Buss (1981) Shyness Scale used in identifying shyness in individuals. Eligible students were randomly assigned to one of three groups each consisting of four subjects. The intervention consisted of 4 - 45 minute instructional-type group counseling sessions conducted over a 4-week period. Repeated measures were administered bi-weekly throughout the study period of 14 weeks. Clearly noticable changes in the positive direction occurred for the majority of subjects on almost all sub-scales. Subjects in the post-intervention phase reported greater coping effectiveness in their target situations, greater acceptance of their shy nature, less intensity of, and disturbance by anxious feelings and less difficulty in taking desired action despite anxiety. Behavioral counts taken pre- and post-intervention also support the positive change findings. Implications for further research are discussed.Education, Faculty of
Graduate
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Kundu, Anirban, and Anirban Kundu. "Aspects of Dzyaloshinskii-Moriya Interaction in Two Dimensional Magnetic Structures." Diss., The University of Arizona, 2018. http://hdl.handle.net/10150/626682.
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Research on topologically protected chiral magnetic structures such as magnetic domain walls (DWs) and skyrmions, have gained extensive interest because of their possible applications in magnetic data storage industries. The recently observed chiral DW structures in ultrathin ferromagnetic lms with perpendicular magnetic anisotropy has been attributed to the presence of a strong Dzyaloshinskii-Moriya interaction (DMI). In this thesis, the DMI mediated by the conduction electrons in two dimensional magnetic systems such as magnetic thin lms or at the interfaces between two magnetic materials has been studied. I calculate the Ruderman-Kittel- Kasuya-Yosida (RKKY) type indirect exchange coupling between two magnetic moments at nite temperature using the free electron band. At high temperature, the coupling strength decays with distance faster than the coupling at zero temperature but the period of oscillation remains same. However, the free electron band alone could not produce DMI. In the next step, I show addition of Rashba spin-orbit coupling (RSOC) with the spin-polarized conduction electron band produces the DMI between two magnetic ions. The essential feature of this DMI is: the coupling strength increases with the strength of RSOC, but decreases signi cantly with the Heisenberg exchange coupling. The DMI calculated with this model well explains the possibility of preferred Neel or Bloch DW structures with specifc chirality.
In addition: I study switching of magnetization with ultrafast laser pulse by inverse Faraday e ect (IFE) where an optically induced non-equilibrium orbital momentum generates an e ective magnetic eld via spin-orbit coupling for magnetization switching. I calculate the magnitude of induced orbital moment for the generic itinerant band and show that magnitude is not large enough to make the switching by a single pulse, however, switching could be possible if multiple pulses are applied to the material.
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André, Marcelo Fabiano 1978. "Sintese de B-piperonil-y-butirolactona e B-lactamas utilizando reações de Morita-Baylis-Hillman." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/250241.
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Orientador: Fernando Antonio Santos CoelhoDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica
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Resumo: As b-piperonil-g-butirolactonas são intermediários importantes, tendo em vista que a partir delas é possível dar origem a uma série de lignanas, classe de substâncias de grande interesse científico, por apresentarem diversas atividades biológicas, tais como: antiretroviral, antitumoral, antimalárica, entre outras. Neste trabalho realizamos estudos visando melhorar a diastereosseletividade na preparação de g-butirolactonas com estereoquímica relativa trans, já que a cis já era preparada com boa diastereosseletividade em nosso laboratório. A metodologia desenvolvida baseia-se na redução de um b-ceto-éster obtido a partir da oxidação de um a-ciano-metil-b-hidroxi-éster, este último obtido com um bom rendimento a partir de uma reação de adição de Michael sobre um aduto de Morita-Baylis-Hillman ( MBH). Na segunda parte do trabalho preparamos b-amino-ésteres a partir dos adutos de Morita-Baylis- Hillman (MBH). Utilizamos como estratégia uma reação de adição do tipo Michael com várias aminas. Os b-amino-ésteres foram obtidos com rendimentos variando de 78-93%. Os produtos foram caracterizados e a estereoquímica relativa foi determinada, por nOe, através da formação de um intermediário oxazinanona. Esses b-amino-ésteres são importantes intermediários para a síntese de heterociclos, tais como b-lactamas e oxazinanonas funcionalizadas.
Abstract: The b-piperonil-g-butirolactones are important synthetic intermediates, since they can be used as substrates for the synthesis of different type of lignans, a class of substances of great scientific interest. Lignans exhibit relevant biological activites, as anti-tumoral, anti-retroviral, anti-malarial, etc. In this work, studies have been carried out aiming at improving the diastereoselectivity for the preaparation of butirolactones having anti relative stereochemistry. A method to synthesize g-butirolactone have already been established in our laboratory. The methodology used was based on the the stereoselective reduction of a b-ketoester prepared from the oxidation of a a-cyanomethyl-b-hydroxy-ester. The latter was promptly prepared, in good yields, from a cyanide 1,4 addition over the double bond of Morita-Baylis-Hillman (MBH) adducts. In the second part of this work, we have prepared several b-amino-esters from Morita-Baylis- Hillman (MBH) adducts. The strategy was based also on a Michael addition of different amines over the double bond of MBH adducts. The b-amino-esters were obtained in good yield. Their stereochemistries were determined by nOe experiments of the corresponding oxazinanones. These b-amino-esters are important intermediates for the synthesis of heterocycles, as b-lactams and functionalized oxazinanones.
Mestrado
Quimica Organica
Mestre em Química
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Regiani, Thaís. "Novas abordagens para o estudo mecanístico da reação de Morita-Baylis-Hillman." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/250261.
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Orientadores: Fernando Antônio Santos Coelho, Marcos Nogueira EberlinDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química
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Resumo: Essa dissertação visa explorar o mecanismo da reação de aza-Morita-Baylis-Hillman (aza-MBH) por espectrometria de massas (ESI-MS). Essa técnica está bem consolidada para o estudo do mecanismo de reações orgânicas. Os dados disponíveis na literatura assumem que o mecanismo dessa reação é similar ao da reação de Morita-Baylis-Hillman (MBH) convencional. Entretanto, existem várias versões assimétricas para a reação de aza-MBH que podem ser consideradas como gerais, o que não ocorre com a reação de MBH. Sendo assim o objetivo desse trabalho foi conhecer as etapas envolvidas no mecanismo da reação de aza-MBH e fornecer subsídios para explicar os pontos em que esses mecanismos diferem. Avaliamos a influência do uso de diferentes bases terciária e de olefinas na reação de aza-MBH. Interceptamos e caracterizamos dois novos intermediários de m/z 665 e m/z 777 que aparentemente desempenham um importante papel no ciclo catalítico da reação de aza-MBH. A formação desses intermediários foi corroborada em um estudo envolvendo o propiolato de metila como componente nucleofílico da reação de aza-MBH. Em outra parte de trabalho monitoramos por ESI-MS uma reação de MBH para demonstrar a habilidade de um aduto de MBH como uma fonte de próton para a etapa lenta da reação. Assim, um aduto contendo um átomo de bromo foi utilizado como fonte de próton. Fomos capazes de interceptar e caracterizar intermediários nos quais essa fonte de próton (aduto MBH bromado) estava ligada. Esses resultados são uma evidência experimental do processo de autocatálise que pode ocorrer durante o desenvolvimento dessa reação. Finalmente, um monitoramento on-line por espectrometria de massas de uma reação de MBH convencional nos permitiu realizar um estudo cinético dessa reação. Esse monitoramento foi realizado utilizando uma nova fonte de ionização ambiente, baseada na ionização por Sonic Spray (V-EASI). A curva cinética nos permitiu acompanhar a reação em tempo real e observar a formação de todos os intermediários transientes do seu ciclo catalítico
Abstract: This dissertation aimed at exploring the monitoring of the mechanism of the aza-Morita-Baylis-Hillman reaction (aza-MBH) by mass spectrometry (ESI-MS). This technique is well established for studying the mechanism of organic reactions. Normally, it is assumed that the mechanism of the aza-MBH reaction is quite similar to the conventional Morita-Baylis-Hillman reaction. However, there are several general asymmetric versions for the aza-MBH reaction, which does not occur with the MBH reaction. The aim of this study was to understand the steps involved in the mechanism of aza-MBH reaction and provide evidences to explain the points at which these mechanisms would differ. We have evaluated the behavior of bases and acrylates often used in the reaction of aza-MBH. We were able to intercept and characterize by tandem MS/MS two new intermediate of m/z 665 and m/z 777 which apparently play an important role in the catalytic cycle of the aza-MBH reaction. The formation of these intermediates was corroborated in a study involving methyl propiolate as nucleophilic for a aza-MBH reaction. The two intermediates have never been cited or featured in this reaction. In another part of this work we monitored a MBH reaction by ESI-MS in order to evaluate the ability of a MBH adduct act as a proton source in the rate-determining step (RDS) of this reaction. Thus, a brominated adduct was used as a source of proton in an anhydrous medium. We were able to isolate and characterize intermediates in which the proton source (brominated adduct MBH) was on. These results provide experimental evidence that the process of autocatalysis may occur during the development of this reaction. Finally, an on-line monitoring of a conventional Morita-Baylis-Hillman by mass spectrometry enabled us to perform a kinetic study of this reaction. This monitoring was carried out using a new ionization source environment based on Sonic Spray ionization (V-EASI). The kinetic curve allowed us to monitor the reaction in real time and observe the formation of all transient intermediates which participate in its catalytic cycle
Mestrado
Quimica Organica
Mestre em Química
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Ferreira, Andre Vargas. "Síntese de aminoácidos não-proteinogênicos enriquecidos em 10B utilizados na Terapia de Captura de Nêutrons por Boro (BNCT)." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/64/64135/tde-03092013-160315/.
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O Glioblastoma Multiforme (GMB), tipo de câncer cerebral mais comum e agressivo, apesar dos recentes avanços na pesquisa em neurociência, é muitas vezes incurável e com prognóstico obscuro. Diante da resistência e da inespecificidade dos tratamentos frente a esses tumores, o maior desafio atualmente está no desenvolvimento de estratégias moleculares mais específicas às células cancerígenas e menos agressivas aos pacientes. A terapia de captura de nêutrons por boro, comumente conhecida como BNCT (do inglês Boron Neutron Capture Therapy) fornece um caminho de destruição seletiva das células tumorais poupando as normais, sendo esta terapia baseada na reação de fissão nuclear entre o 10B, um dos isótopos estáveis de boro, e nêutrons de baixa energia. Destaca-se a utilização de isótopos estáveis na área biomédica pelo fato destes serem inócuos ao organismo dos pacientes e não possuírem limite de dosagem. Desta forma, o objetivo do presente trabalho consiste na síntese do principal fármaco utilizado na BNCT, o L-4-borofenilalanina enriquecido em 10B. Para isso, utilizou-se da reação de Morita-Baylis-Hillman (MBH) cuja definição geral é uma condensação entre carbonos eletrofílicos sp2 e a posição \'alfa\' de uma olefina com grupos retiradores de elétrons ativada por uma amina terciária ou uma fosfina, gerando uma nova ligação \'sigma\'C-C. Essa reação apresenta algumas vantagens que evidenciam as reações de MBH como uma metodologia sintética eficiente: são regio e quimioseletivas; possuem uma elevada economia de átomos, necessitam condições brandas de trabalho fornecendo. Estabeleceu-se metodologia para a síntese do 4-bromofenilalanina, precursor do fármaco L-4-borofenilalanina por meio de duas abordagens sintéticas inéditas e distintas. A ampliação do escopo dessa sequência de reações para sintetizar outros aminoácidos não-proteinogênicos demonstra a robustez da nova rota sintética abrindo a possibilidade de síntese de outros aminoácidos enriquecidos em isótopos estáveis de elementos leves com aplicação biomédica. A primeira abordagem sintética compreendeu 6 etapas e foi possível obter um rendimento global de 24%. A segunda abordagem sintética foi realizada em 4 etapas possibilitando obter o mesmo aminoácido com rendimento global de 46%Glioblastoma Multiforme (GMB), a most common and aggressive type of brain cancer, in spite of recent advances in neuroscience research, is often incurable and the prognosis is obscure. In front of the resistance and specificity of the treatments against these tumors, the biggest challenge nowadays is to develop molecular strategies more specific to tumor cells and less aggressive for the patient. Boron Neutron Capture Therapy (BNCT) provides a path of selective destruction of tumor cells sparing the normal ones, which this therapy based on nuclear fission reaction between 10B, one of the stable isotopes of boron and low-energy neutrons. Emphasizes the use of stable isotopes in the biomedical area because these are innocuous to the body of the patients and do not have limit dosage. Thus, the aim of this master is the synthesis of the main drug used in BNCT, the L-4-boronophenylalanine enriched in 10B. For this, we used the Morita-Baylis-Hillman (MBH) which definition is a condensation between sp2 eletrophilic carbon and the position \'alfa\' of an olefin activated by tertiary amine or phosphine, generating a new \'sigma\'C-C bond. This reaction has some advantages that evidence the reactions of MBH as an efficient synthetic methodology: are regio and quimioselective, have high atom economy, require mild conditions providing polifunctionalized molecules that through small changes in chemical structure can generate a series of synthetic intermediates, pharmaceuticals, etc. It was established methodology for the synthesis of 4-bromophenylalanine, drug precursor of L-4-boronophenylalanine through two distinct and previously unreleased synthetic approaches. The expansion of the scope of this sequence of reactions to synthesize other non-proteinogenic amino acids demonstrates the robustness of the new synthetic route opening up the possibility of synthesis of other amino acids enriched in stable isotopes with biomedical application. The first approach consisted 6 steps and it was possible to obtain an overall yield of 24%. The second approach was performed in 4 synthetic steps obtaining the same amino acid with an overall yield of 34.77%
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Cótes, Lourenço Candido. "Avaliação do emprego epidural de morfina ou morfina-fentanil, associados à lidocaína, em cães." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/10/10137/tde-09102012-105723/.
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Os opióides de curta duração e de alta potencia analgésica, como o fentanil, embora amplamente utilizados em cães, ainda são pouco empregados pela via epidural nesta espécie. O presente estudo teve como objetivo avaliar a associação do anestésico local lidocaína à morfina ou à combinação morfina-fentanil, pela via epidural. Foram analisados os efeitos cardiovasculares, respiratórios bem como a analgesia pós-operatória, em cães submetidos a cirurgia de joelho. Para tanto, 24 animais da espécie canina foram aleatoriamente divididos em 2 grupos. Todos os animais receberam acepromazina (0,05 mg/kg), foram induzidos com propofol (5 mg/kg) e mantidos em anestesia inalatória. Os animais do GRUPO I foram tratados com lidocaína (5mg/kg) associada a morfina (0,1mg/kg) e os animais do GRUPO II receberam, pela via epidural, a combinação lidocaína-morfina-fentanil, sendo este último na dose de 2µ/kg. Parâmetros como frequência cardíaca, respiratória, pressão arterial (sistólica, média e diastólica) foram mensurados, bem como pH e gases sanguíneos. Para a avaliação da analgesia foram utilizadas a escala Analógica-visual (EAV), a escala proposta por Lascelles, 1994 e a termoalgimetria. Amostras de sangue foram coletadas para posterior dosagem de cortisol e Interleucina-06. O período de avaliação imediata foi de 06 horas após a cirurgia, sendo os animais reavaliados no período de 24 horas após o procedimento. No tocante aos parâmetros cardiorrespiratórios os grupos se comportaram de maneira muito semelhante. Entretanto, pode-se observar que os animais tratados com a combinação lidocaína-fentanil-morfina apresentaram menor escore de dor quando avaliados pelas escalas do estudo no período pós-operatório. De fato verificou-se diferença significativa nos escores da EAV (p <0,05) nos tempos T180 e T360; na escala de Lascelles obteve-se diferença estatística nos tempos T180, T360 e T24h e na termoalgimetria houve diferença estatística nos tempos T180, T360 e T24h. A analgesia de resgate foi necessária em 3 animais do Grupo II, enquanto no Grupo I a necessidade desta medicação foi observada em 6 animais. Pode-se concluir, com os resultados obtidos, que a associação do fentanil no protocolo de anestesia epidural, promoveu adequada analgesia perioperatória, além de produzir um efeito sinérgico-residual, o que melhorou a analgesia pós-operatória, diminuindo a necessidade de analgesia de resgate.Short duration opioids and high potency analgesics such as fentanyl, although widely used in dogs are seldom used for epidural anesthesia in this species. This study aimed to evaluate the association of lidocaine with morphine or morphine-fentanyl combination, epidurally. 24 dogs were randomly divided into two groups. All animals received acepromazine intramuscularlly (0.05 mg / kg), were induced with propofol (5 mg / kg) and maintained under inhalation anesthesia. The animals in group I were treated with lidocaine (5 mg / kg) combined with morphine (0.1 mg / kg) epidurally and the animals of group II received epidurally, the combination lidocaine-morphine-fentanyl, the latter at the dose of 2µ/kg. Parameters such as heart and respiratory rate, blood pressure (systolic, mean and diastolic), blood gases and pH were measured. For the assessment of analgesia were used visual-analogue scale (VAS), the scale proposed by Lascelles and thermoalgimetry. Blood samples were collected for later determination of cortisol and interleukin-06. The evaluation period was 06 hours after surgery, the animals were re-evaluated within 24 hours after the procedure. Except the cardiorespiratory parameters, the groups were similarly. However, was observed that animals treated with the combination lidocaine-fentanyl-morphine had lower pain scores in the postoperative period. In fact there were significant differences in VAS scores (p <0.05) at times T180 and T360; in Lascelles scores at times T180, T360 and T24h and there were no statistical diferences in thermoalgimetry at times T180, T360 and T24h. The rescue analgesia was required in three animals in Group II, and six animals in Group I. It can be concluded that the combination of fentanyl in epidural anesthesia protocol, promoted adequate perioperative analgesia, producing synergistic and residual effects, which improved postoperative analgesia.
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Aroyan, Carrie Elizabeth. "Harnessing single amino acid catalysis : development of the enantioselective intramolecular Morita-Baylis-Hillman and Rauhut-Currier reactions and studies toward the synthesis of (+)-SCH 642305." Thesis, Boston College, 2008. http://hdl.handle.net/2345/959.
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Thesis advisor: J. Scott MillerThe development of two catalytic asymmetric synthetic methods is presented and culminates with studies of their application to the synthesis of a natural product. The intramolecular variant of the Morita-Baylis-Hillman (MBH) reaction has remained almost untouched by asymmetric catalysis. A significant advance in the field is demonstrated with the development of a highly enantioselective intramolecular MBH reaction employing a co-catalytic system of N-methylimidazole (NMI) and pipecolinic acid (Pip). The optimization of various reaction parameters and the use of protic conditions (THF-H2O, 3:1) afforded the desired products in up to 82% yield and 80% ee. The extension of this methodology to include the use of vinylogous reaction partners in the Rauhut-Currier (RC) reaction has been achieved, establishing the first highly enantioselective RC reaction. A single amino acid derivative of cysteine, in the presence of potassium tert-butoxide and a critical concentration of water in acetonitrile, was demonstrated to function as a highly selective catalyst providing products in up to 95% ee. Finally, the application of the MBH and RC reactions to the synthesis of complex molecules presents highly useful methodology for the formation of a new C–C bond in the generation of densely functionalized enantiopure products. Preliminary studies toward the application of this methodology to the stereoselective synthesis of (+)-Sch 642305 are described. Examination of the catalyst’s ability to dictate the stereoselectivity of the key step (catalyst control) and allow the synthesis of both the natural product, and difficult-to-obtain unnatural stereoisomeric analogs, will be the subject of on-going studies
Thesis (PhD) — Boston College, 2008
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Chemistry
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Araújo, Fabiana Amaral. "Ação da morina sobre coelhos normais e diabéticos: parâmetros metabólicos e morfologia pancreática." Universidade Federal de Viçosa, 2002. http://www.locus.ufv.br/handle/123456789/11288.
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Fundação de Amparo à Pesquisa do Estado de Minas Gerais
O efeito do flavonóide morina foi testado sobre o peso corporal e os constituintes sangüíneos de coelhos normais e diabéticos durante o período de 30 dias. Foram utilizados 24 coelhos da raça Nova Zelândia, sendo 12 animais de cada sexo, distribuídos de forma casualizada em seis grupos experimentais (grupo controle T0, grupo controle diabético T0, grupo controle T30, grupo normal tratado T30, grupo controle diabético T30 e grupo diabético tratado T30). O diabetes mellitus foi induzido nos animais experimentais através de injeção intravenosa de aloxano na dose de 100 mg/kg de peso corporal. Para se evitar a hipoglicemia, decorrente do rompimento das células β e liberação de insulina, foram feitas aplicações de 10mL de solução de glicose 50% p/v, via intraperitonial, após 4, 8 e 12 horas do início da indução. Após a indução de diabetes mellitus aguardou-se um período de seis dias para o desenvolvimento da doença. Amostras de sangue foram coletadas através da incisão no plexo venoso retro orbital do olho utilizando- se a extremidade aguda de um tubo capilar. As determinações do peso e dos níveis séricos de glicose, colesterol total, triglicerídeos, albumina e creatinina foram feitas após 30 dias de tratamento. Os animais que tiveram glicemia acima de 180 mg/dL foram considerados diabéticos. Animais dos grupos controle tratado e diabético tratado receberam, diariamente uma cápsula de 5mg do flavonóide morina. Não foram observadas diferenças significativas entre os tratamentos aplicados nem para os animais normais nem para os diabéticos. Ao final do ensaio biológico os animais foram sacrificados e foi coletado o pâncreas de dois espécimes de cada grupo com objetivo de verificar o efeito diabetogênico do aloxano e o efeito regenerador da morina sobre as células β pancreáticas através de estudo histológico. Não foram observadas diferenças significativas entre os tratamentos aplicados aos coelhos normais nem aos diabéticos. Pela análise histológica foi comprovada a eficácia do aloxano na indução do diabetes mellitus, pela ausência de células β nas ilhotas pancreáticas de animais tratados e não tratados e que a morina não teve efeito regenerador sobre essas células pancreáticas na dose e no tempo empregados no experimento.
The effect of the morin flavonoid on the body weight and blood constituents of normal and diabetic rabbits was tested for the period of thirty days. Twenty-four rabbits of the New Zealand breed were used; there were twelve males and twelve females, randomly distributed into six experimental groups (control group T0, diabetic control group T0, control group T30, diabetic control group T30, healthy treated group, and diabetic treated group). The diabetes mellitus was induced to the experiment animals through an alloxan intravenous injection, with the dosage of 100 mg/kg of body weight. In order to avoid hypoglycemia resulting from the breaking of the β-cells and liberation of insulin, dosages of 10mL of glucose solution 50% p/v were applied intraperitonial, 4, 8 and 12 hours after the beginning of the diabetes mellitus induction. After the induction of the diabetes mellitus, it was necessary to wait for six days, until the disease developed. Blood samples were collected through the incision in the eye venous plexus retro orbital, using the sharp edge of a capillary tube. The measurements of body weight and plasma levels of glucose, total cholesterol, triacylglycerol, albumin and creatinin occurred after 30 days of treatment. The animals that presented a glycaemia level higher than 180mg/dL were considered diabetics. The animals in the treated control and treated diabetic groups received a 5 mg capsule of flavonoid morin every day. Significant differences were not observed among the treatments applied, neither for the normal animals nor for the diabetic animals. At the end of the biological experiment, the animals were sacrificed and the pancreas of two animals of each group were collected in order to observe the diabetogenic effect of the alloxano and the regeneration effect of the morin on the pancreatic β-cells, through a morphological study. Significant differences were not observed between the treatments applied to the normal rabbits and to the diabetic rabbits. Through the histological analysis, the efficiency of the alloxano in induction of the diabetes mellitus was verified, through the absence of β-cells in the pancreatic islets. It was also noticed that the morin had no regeneration effect on those pancreatic cells if the dose and the time applied in the experiment are used.
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Japiassu, Kamila Bohne. "Biossíntese catalisada por Beauveria bassiana ATCC 7159 de um novo flavonóide metilglicosilado potencialmente antioxidante e antifúngico." Universidade Federal de Goiás, 2018. http://repositorio.bc.ufg.br/tede/handle/tede/8514.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Biosynthesis of compounds catalysed by microorganisms is an innovative strategy in the functionalization of natural and synthetic products. The application of microorganisms in the production of new bioactive compounds is presented as a promising tool and a great ally of green chemistry. Studies indicate that the morin has interesting antioxidant and antifungal activities. Thus, the objective of this study is the production of morin derivatives through biosynthesis, and the evaluation of its antioxidant and antifungal activities. To screen and identify the most promising strains, 18 filamentous fungi were selected and aliquots of a spore suspension were transferred to 250 ml Erlenmeyers containing 100 ml of a liquid culture medium (20 g of glucose, 0.5 g of yeast extract, 0.5 g of soy peptone, 0.5 g of NaCl, 0.5 g of K2 HPO4). The microorganisms were incubated at 200 rpm and 28 °C for 65 hours. After growth, 25 mg of morin were solubilized in ethanol and added to each Erlenmeyer. After 96 hours of incubation, extraction and subsequent purification were performed on a silica-filled chromatographic column and preparative chromatography. The obtained derivative was characterized by Nuclear Magnetic Resonance of Hydrogen and Carbon (NMR1H13C) and Mass Spectrometry (MS). In addition, antioxidant, antifungal and cytotoxicity activities were evaluated. The results showed that ten strains were able to catalyze the biosynthesis of up to four morin derivatives. Beauveria bassiana ATCC 7159 was selected to conduct the reaction staggering, where it was possible to obtain three ineded derivatives of the starting compound, leading to the isolation and purification of a methylglycosylated major product, termed morin 4’-O-β-D-(4’’-O-methyl) glucopyranoside. The results obtained through the evaluation of antioxidant and antifungal activities showed a good performance of the evaluated compounds. In addition, the obtained compost showed a low red blood cell cytotoxicity (0.6-1.2%). In silico studies have evaluated potential biological activities for morin and its derivatives. The derivative obtained by biosynthesis catalysed by B. bassiana ATCC 7159 is unprecedented and has good antioxidant, antifungal and low cytotoxicity profiles in red blood cells.
A biossíntese de compostos catalisada por micro-organismos é uma estratégia inovadora na funcionalização de produtos naturais e sintéticos. Esta estratégia é apresentada como uma ferramenta promissora e grande aliada da química verde na produção de novos compostos bioativos. A morina é um flavonóide que possui reconhecidas atividades antioxidante e antifúngica. Assim, o objetivo deste estudo é a produção de derivados da morina através de biossíntese, e a avaliação de suas atividades antioxidante, antifúngica e citotóxica em hemácias. Para realizar a triagem e a identificação da cepa mais promissora, 18 fungos filamentosos foram empregados; alíquotas de uma suspensão de esporos foram transferidas para Erlenmeyers de 250 mL contendo 100 mL de diferentes meios de cultura líquido (Glicose, PDSM e Czapek). Os micro-organismos foram incubados a 200 rpm e 28 °C durante 65 horas. Após o crescimento, 25 mg/mL de morina foram solubilizados em etanol e adicionados a cada Erlenmeyer. Ao final do período de 96 horas de incubação foi realizada a extração e posterior purificação em coluna cromatográfica preenchida com silica e cromatografia preparativa. Os produtos foram monitorados por Espectrometria de Massas (EM) e o produto majoritário obtido foi caracterizado por Ressonância Magnética Nuclear de Hidrogênio e de Carbono (RMN1H13C) e Espectrometria de Massas (EM). Além disso, a atividade antioxidante, antifúngica e a citotoxicidade em hemácias da morina e do produto majoritário obtido foram avaliadas. Os resultados mostraram que dez cepas foram capazes de catalisar a biossíntese de até três derivados da morina. A Beauveria bassiana ATCC 7159 foi selecionada para conduzir o escalonamento da reação em biorreator de tanque agitado, uma vez que essa cepa foi capaz de biocatalizar o maior número de derivados. Foi possível a obtenção de três derivados inéditos do composto de partida, conduzindo ao isolamento e purificação de um produto majoritário metilglicosilado, denominado morina 4’-O-β-D-(4’’-O-metil) glucopiranosídeo. A atividade antioxidante avaliada por voltametria cíclica de pulso diferencial apresentou 5 picos de oxidação para o derivado metilglicosilado e 2 picos de oxidação para a morina. Na avaliação da atividade antifúngica, o derivado obtido, quando comparado com a morina, apresentou menor concentração inibitória minima para cepa L18 de Cryptococcus sp. Além disso, o composto obtido apresentou uma baixa citotoxicidade em hemácias (0.6-1.2%). Estudos in silico avaliaram as potenciais atividades biológicas para a morina e seus derivados. O derivado obtido através de biossíntese catalisada por B. bassiana ATCC 7159 é inédito e possui bons perfis antioxidante, antifúngico e baixa citotoxicidade em hemácias.
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Butenko, Ganna. "Phenomenological theory of chiral states in magnets with Dzyaloshinskii-Moriya interactions." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-108447.
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This thesis presents the theoretical studies of chiral magnetic structures, which exist or are affected by antisymmetric Dzyaloshinskii-Moriya interactions. The theoretical approach is based on the phenomenological model of ferromagnetic materials lacking inversion symmetry. Equilibrium magnetic states are described as static structures in the micromagnetic low temperature limit with a fixed magnitude of the magnetization. The studies are focused on two cases: (i) magnetization structures that are affected by chiral exchange so that a particular chirality of these structures is selected, and (ii) novel solitonic states that are called chiral Skyrmions and only exist because of the chiral exchange.
Vortex states in magnetic nanodisks provide the simplest example of a handed magnetization structure, where effects of the chiral couplings may become noticeable. A chiral exchange here favours one chirality of such a vortex state over the other. This effect can stem from surface-induced or other defect-related chiral Dzyaloshinskii-Moriya exchange. The different chiral versions of the vortex states are shown to display strong dependencies on the materials properties of such nanodisks. Within a micromagnetic model for these effects, numerical calculations of the shape, size, and stability of the vortices in equilibrium as functions of magnetic field and the material and geometrical parameters provide a general analysis of the influence of the broken mirror symmetry caused by the surface/interfaces or structural defect on their properties. The Dzyaloshinskii-Moriya interactions impose differences in the energies and sizes of vortices with different chirality: these couplings can considerably increase sizes of vortices with one sense of rotation and suppress vortices with opposite sense of rotation. Torsions related to lattice defects can cause similar to the surface-induced chiral couplings. A general phenomenological magneto-elastic formulation for this torsional chirality selection is given. It is applied to calculate similar effects on vortex states in magnetic disks with a screw dislocation at their center.
In systems with strong chiral exchange the magnetic equilibrium states themselves become chiral twisted structures. The most interesting structures in this context are the two-dimensional solitonic states that are now known as chiral Skyrmions. The properties and stability of multiply twisted states composed of these particle-like units are the subject of the second part of this thesis. These states compete with the well known onedimensionally modulated helical states in non-centrosymmetric magnetic systems. Studies of modulated states in cubic helimagnets have shown, that in absence of additional effects, the only thermodynamically stable state is a cone helix. Uniaxial distortions, that can be caused by uniaxial stresses in the bulk samples or arise due to surface effects in thin films, suppress the helical states and stabilize Skyrmion lattices in a broad range of thermodynamical parameters. Using the phenomenological theory for modulated and localized states in chiral magnets, the equilibrium parameters of the Skyrmion and helical states have been derived as functions of applied magnetic field and induced uniaxial anisotropy. These results show that due to a combined effect of induced uniaxial anisotropy and an applied magnetic field, Skyrmion lattices can be formed as thermodynamically stable states.
The theoretical results provide a comprehensive description of the evolution of modulated states in an applied magnetic field depending on type of anisotropy. The cases of a uniaxial anisotropy of easy axis and easy plane type with fields applied along its axis are investigated in detail. Existence of Skyrmion-lattice states in the easy axis case as thermodynamic field-induced phase is demonstrated. The results explain recent observation of Skyrmion lattices by magnetic Lorentz microscopy in thin foils of cubic chiral magnets. In systems with easy plane type of anisotropy, Skyrmion states do not form thermodynamic phases in applied fields along the axis. However, distorted Skyrmion phases can exist in fields applied perpendicularly to the axis. In this configuration of anisotropy axis and fields, both the helical states and the Skyrmions display elliptical distortions. The investigated micromagnetic model maps out the basic helical and Skyrmionic states expected to exist in cubic and nearly cubic chiral magnets.