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

Funcionalização de 3,4,6-tri-O-acetil-D-glucal via click chemistry e reações de acoplamento cruzado catalizado por paládio / Functionalization of 3,4,6-tri-O-acetyl-D-glucal via click chemistry and palladium-catalyzed cross-coupling reactions

Shamim, Anwar 25 July 2017 (has links)
A funcionalização de 3,4,6-tri-O-acetil-D-glucal foi realizada utilizando reações de acoplamento cruzado (Sonogashira e Stille), ciclo-adições de azida-alcino (Click chemistry) e ciclização nucleófila promovida por eletrófilo. Utilizando estas reações juntamente com as já referidas transformações de grupos funcionais e reações de rearranjo de Ferrier, as bibliotecas de compostos à base de glucal foram sintetizadas e observadas em algumas moléculas fluorescência e outras foram disponibilizadas para avaliação de atividade biológica. Na primeira parte, foram sintetizadas bibliotecas de derivados de bis- e tris-triazolil-glicosila a partir de 3,4,6-tri-O-acetil-D-glucal utilizando as reações acima mencionadas. A segunda parte deste trabalho consiste em sintetizar uma biblioteca de derivados glucal de 2-alquinilo usando um acoplamento de Sonogashira livre de cobre e ligante, seguido por aplicações sintéticas destes alquinos glucais. A hidrostanação regioselectiva catalisada por paládio destes glucanos 2-alquinilo foi realizada utilizando hidreto de tributilestanho para gerar uma biblioteca de derivados estanil regioisoméricos de glucal. Além disso, estes derivados de 2-alquinil-glucal sintetizados na primeira parte também foram utilizados na ciclização nucleofílica 5-endo-dig promovida por eletrófilos para proporcionar derivados de glucal bicíclicos. Na parte final, os derivados de estanho de glucal foram utilizados para sintetizar bibliotecas de derivados de 2-alcenil glucal substituído. Esta parte inclui também transformações de grupos funcionais e acoplamentos cruzados (Stille e Sonogashira), bem como click chemistry para gerar bibliotecas de derivados de 2-alquenil-D-glucal alquinilo e triazolilo substituídos. Na maioria dos casos os produtos foram obtidos em rendimentos muito bons a excelentes que foram analisados utilizando RMN, Infra vermehlo, espectrometria de massas de alta resolução e outras técnicas analíticas quando aplicável. / Functionalization of 3,4,6-tri-O-acetyl-D-glucal has been performed using cross-coupling (Sonogashira and Stille) reactions, azide-alkyne cycloadditions (Click chemistry) and electrophile-promoted nucleophilic alkyne cyclizations. Using these reactions along with the already reported functional group transformations (FGT) and Ferrier rearrangement reactions, libraries of glucal-based compounds were synthesized with members of characteristic photophysical and potential biological properties. In the first part, the synthesis of libraries of bis- and tris-triazolyl glycosyl derivatives is described starting from 3,4,6-tri-O-acetyl-D-glucal using the above-mentioned reactions. In the second part of this work, the synthesis of a library of 2-alkynyl glucal derivatives using a copper and ligand-free Sonogashira coupling, followed by synthetic applications of these glucal alkynes is reported. Palladium-catalyzed regioselective hydrostannation of these 2-alkynyl glucals was performed using tributyltin hydride to generate a library of regioisomeric stannyl derivatives of glucal. Moreover, these 2-alkynyl glucal derivatives synthesized in the first part were also used in electrophile-promoted nucleophilic 5-endo-dig cyclization to afford bicyclic glucal derivatives. In the final part, the use of stannyl derivatives of glucal to synthesize libraries of substituted 2-alkenyl glucal derivatives is described. This part also includes certain functional group transformations and cross-couplings (Stille and Sonogashira) as well as click chemistry to generate libraries of alkynyl and triazolyl substituted 2-alkenyl-D-glucal derivatives. In most of the cases, the products were obtained in very good to excellent yields and were analyzed using 1H NMR, 13C NMR, FTIR, HRMS, and other analytic techniques where applicable
12

Funcionalização de 3,4,6-tri-O-acetil-D-glucal via click chemistry e reações de acoplamento cruzado catalizado por paládio / Functionalization of 3,4,6-tri-O-acetyl-D-glucal via click chemistry and palladium-catalyzed cross-coupling reactions

Anwar Shamim 25 July 2017 (has links)
A funcionalização de 3,4,6-tri-O-acetil-D-glucal foi realizada utilizando reações de acoplamento cruzado (Sonogashira e Stille), ciclo-adições de azida-alcino (Click chemistry) e ciclização nucleófila promovida por eletrófilo. Utilizando estas reações juntamente com as já referidas transformações de grupos funcionais e reações de rearranjo de Ferrier, as bibliotecas de compostos à base de glucal foram sintetizadas e observadas em algumas moléculas fluorescência e outras foram disponibilizadas para avaliação de atividade biológica. Na primeira parte, foram sintetizadas bibliotecas de derivados de bis- e tris-triazolil-glicosila a partir de 3,4,6-tri-O-acetil-D-glucal utilizando as reações acima mencionadas. A segunda parte deste trabalho consiste em sintetizar uma biblioteca de derivados glucal de 2-alquinilo usando um acoplamento de Sonogashira livre de cobre e ligante, seguido por aplicações sintéticas destes alquinos glucais. A hidrostanação regioselectiva catalisada por paládio destes glucanos 2-alquinilo foi realizada utilizando hidreto de tributilestanho para gerar uma biblioteca de derivados estanil regioisoméricos de glucal. Além disso, estes derivados de 2-alquinil-glucal sintetizados na primeira parte também foram utilizados na ciclização nucleofílica 5-endo-dig promovida por eletrófilos para proporcionar derivados de glucal bicíclicos. Na parte final, os derivados de estanho de glucal foram utilizados para sintetizar bibliotecas de derivados de 2-alcenil glucal substituído. Esta parte inclui também transformações de grupos funcionais e acoplamentos cruzados (Stille e Sonogashira), bem como click chemistry para gerar bibliotecas de derivados de 2-alquenil-D-glucal alquinilo e triazolilo substituídos. Na maioria dos casos os produtos foram obtidos em rendimentos muito bons a excelentes que foram analisados utilizando RMN, Infra vermehlo, espectrometria de massas de alta resolução e outras técnicas analíticas quando aplicável. / Functionalization of 3,4,6-tri-O-acetyl-D-glucal has been performed using cross-coupling (Sonogashira and Stille) reactions, azide-alkyne cycloadditions (Click chemistry) and electrophile-promoted nucleophilic alkyne cyclizations. Using these reactions along with the already reported functional group transformations (FGT) and Ferrier rearrangement reactions, libraries of glucal-based compounds were synthesized with members of characteristic photophysical and potential biological properties. In the first part, the synthesis of libraries of bis- and tris-triazolyl glycosyl derivatives is described starting from 3,4,6-tri-O-acetyl-D-glucal using the above-mentioned reactions. In the second part of this work, the synthesis of a library of 2-alkynyl glucal derivatives using a copper and ligand-free Sonogashira coupling, followed by synthetic applications of these glucal alkynes is reported. Palladium-catalyzed regioselective hydrostannation of these 2-alkynyl glucals was performed using tributyltin hydride to generate a library of regioisomeric stannyl derivatives of glucal. Moreover, these 2-alkynyl glucal derivatives synthesized in the first part were also used in electrophile-promoted nucleophilic 5-endo-dig cyclization to afford bicyclic glucal derivatives. In the final part, the use of stannyl derivatives of glucal to synthesize libraries of substituted 2-alkenyl glucal derivatives is described. This part also includes certain functional group transformations and cross-couplings (Stille and Sonogashira) as well as click chemistry to generate libraries of alkynyl and triazolyl substituted 2-alkenyl-D-glucal derivatives. In most of the cases, the products were obtained in very good to excellent yields and were analyzed using 1H NMR, 13C NMR, FTIR, HRMS, and other analytic techniques where applicable
13

Development of the 5-exo-dig/Prins Reaction and Efforts towards the Total Synthesis of (±)-Magellanine

Bétournay, Geneviève L. 02 November 2012 (has links)
Gold catalysis has attracted much attention within the chemical community in recent years, and its importance as a synthetic tool has only started to be uncovered. This thesis describes the development of a gold(I) catalyzed transformation and its application to the synthesis of a structurally unique Lycopodium alkaloid, Magellanine. Although there have been a few reports on the synthesis of the magellanane core to date, the approach described herein would represent a new and efficient strategy to construct the angularly fused tetracyclic core. The 5 exo dig/Prins reaction that would be the key step of the synthesis was first developed and studied on a model substrate, enabling the verification of the hypothesis that this transformation could indeed form the A and B rings of Magellanine and be applied to its synthesis. This reaction formed the tricyclic products in good yields and in good exo:endo ratios. The synthesis of Magellanine was undertaken, but problems of isomerization prevented the synthesis of the desired 5 exo dig/Prins substrate, which contained the C and D rings of Magellanine with a cis relationship at the ring junction. However, an almost identical substrate, save for a trans configuration between the C and D rings instead of the cis configuration, was prepared and served in further establishing the applicability of this methodology to the synthesis of Magellanine by successfully undergoing the 5-exo-dig/Prins reaction and generating the tetracyclic products. Studies of the steps following the key transformation were performed on the model substrate, allowing for the evaluation of these steps prior to their use in the synthesis. The results of the studies indicate a possible need to revisit the order in which the steps should be carried out. Promising solutions to the different obstacle encountered during the work are presented, demonstrating how the synthesis of Magellanine through a route featuring the 5-exo-dig/Prins cyclization is attainable.
14

Two genes, dig-1 and mig-10, involved in nervous system development in C. elegans

Burket, Christopher T 15 November 2002 (has links)
"We are using genetic and molecular techniques to study a simple model organism, C. elegans, to determine the cues involved in the formation of the nervous system. Two molecules currently being studied in the laboratory play roles in the formation of the IL2 neurons, a class of sensory neurons in C. elegans. The first gene, dig-1, influences the sensory process or dendrite and is involved in adhesion as well as potentially providing directional information during development. The second gene, mig-10, influences the axon and may be involved in a cell signal cascade. Genetic screens of C. elegans using Ethyl methyl sulfonate (EMS) as a mutagen resulted in the isolation of mutants with defects in the IL2 sensory map; sensory processes followed aberrant paths, appearing to be defasciculated. Complementation tests showed that the mutations failed to complement n1321, a known allele of dig-1; thus, these new mutations were alleles of dig-1 (Ryder unpub. results). Several of these new alleles of dig-1, including nu336 and n1480, have been further studied to elucidate the role of this gene in sensory map formation. A dig-1 candidate gene was identified that encodes a protein that is a member of the immunoglobulin super-family (IgSF). The candidate gene is predicted to be a large gene, with a transcript of approximately 45Kb. The encoded protein contains three distinct regions and is similar to the hyalectan family of proteoglycans. N terminal region 1 contains immunoglobulin and fibronectin-like domains. Central region 2 is an area that is highly repeated with a potential to have GAGs attached. C-terminal region 3 contains domains associated with adhesion. Polymerase chain reaction (PCR) products from alleles nu336 and n1480 were amplified and sequenced from the candidate gene. The DNA lesion present in the candidate gene from both alleles fit the method for how that mutation was generated. The point mutation in allele nu336 removes a potential glycosylation site. The large re-arrangement in allele n1480 truncates the transcript, suggesting that the protein is also truncated. The sequencing results along with rescuing data (R. Proenca, personal communication) showed that the candidate gene for dig-1 was the gene of interest. Each of the alleles was further studied to determine how severe that allele was by looking at the neuronal process aspect and the brood size as well as displacement of the gonad. In general, alleles with severe defects in the nervous system also had severe gonad displacement, suggesting the gene functions similarly in the two tissues. To determine if the gene was expressed at the RNA level, reverse transcriptase polymerase chain reaction (RT-PCR) was used. Most of the RT-PCRs amplified a cDNA of the appropriate size that showed dig-1 was expressed at the RNA level. RT-PCR further suggested that all three regions were in one transcript as well as confirming part of the predicted exon structure to be correct. In addition, northern analysis showed the presence of a large transcript in wildtype worms as well as a smaller truncated transcript from allele n1480. To investigate developmental differences mixed stage of RNA and embryonic RNA from wildtype animals were compared using gene specific primers. The initial RT-PCR showed potential alternative splicing occurring at the 5? end of the gene during development. To examine expression at the protein level, two recombinant proteins from dig-1 were successfully made by cloning cDNA products from the 5?and 3? end of dig-1. The constructs were sequenced and shown to be in frame. The recombinant proteins (Ant1Con1 and Ant3Con3) were mass produced and sent to a commercial source for injection into pre-screened rabbits. Western analysis showed the presence of an antibody in the serum from two of the rabbits. These antibodies should prove useful in future determination of correctness of our models of DIG-1 function. IgSF members have been shown to have many roles in nervous system development. DIG-1 could act in either an attractive or a repellent role to position sensory processes during development. DIG-1 might also change its function over time; early in development DIG-1 could be adhesive and later become repellant as more sugars are added. The gene mig-10 is involved in sensory map formation. To localize MIG-10 expression, several transgenic animals were generated by injection of two constructs that should recombine in the worm to create a MIG-10::GFP fusion protein. Ten transgenic lines were generated and screened by PCR for the presence of the correct recombinant construct. If this construct makes functional, rescuing protein, the GFP expression should reflect the expression pattern of the MIG-10 protein."
15

Development of the 5-exo-dig/Prins Reaction and Efforts towards the Total Synthesis of (±)-Magellanine

Bétournay, Geneviève L. 02 November 2012 (has links)
Gold catalysis has attracted much attention within the chemical community in recent years, and its importance as a synthetic tool has only started to be uncovered. This thesis describes the development of a gold(I) catalyzed transformation and its application to the synthesis of a structurally unique Lycopodium alkaloid, Magellanine. Although there have been a few reports on the synthesis of the magellanane core to date, the approach described herein would represent a new and efficient strategy to construct the angularly fused tetracyclic core. The 5 exo dig/Prins reaction that would be the key step of the synthesis was first developed and studied on a model substrate, enabling the verification of the hypothesis that this transformation could indeed form the A and B rings of Magellanine and be applied to its synthesis. This reaction formed the tricyclic products in good yields and in good exo:endo ratios. The synthesis of Magellanine was undertaken, but problems of isomerization prevented the synthesis of the desired 5 exo dig/Prins substrate, which contained the C and D rings of Magellanine with a cis relationship at the ring junction. However, an almost identical substrate, save for a trans configuration between the C and D rings instead of the cis configuration, was prepared and served in further establishing the applicability of this methodology to the synthesis of Magellanine by successfully undergoing the 5-exo-dig/Prins reaction and generating the tetracyclic products. Studies of the steps following the key transformation were performed on the model substrate, allowing for the evaluation of these steps prior to their use in the synthesis. The results of the studies indicate a possible need to revisit the order in which the steps should be carried out. Promising solutions to the different obstacle encountered during the work are presented, demonstrating how the synthesis of Magellanine through a route featuring the 5-exo-dig/Prins cyclization is attainable.
16

Vytvoření metodické řady cvičení pro specializaci libero ve volejbalu / The creation of a methodical series of exercises for the specialization of the libero in volleyball.

Dostálová, Veronika January 2018 (has links)
In this Master's thesis I am focusing on the creation of a series of exercices for the libero player in volleyball. Exercises focus on the training of specific activities that are mandatory while participating in the game: passing, digging, setting and covering. In the description of individual game activities, always emphasize the key moments of training. The first part focuses on introducing readers to the theoretical basics of volleyball. The main focus is on the detailed description and analysis of the key gaming activities of libero such as mentioned before. The second part of the Master's thesis consists of the exercises I have created for libero player specialization. Exercises are divided into four parts, according to individual game activities. Exercises shown in kinograms (phased footage from the video that is verbally described). Attached to the Master's thesis is a video with a complete series of skill developing exercises with comments. Key words: libero, methodical series, pass, set, dig, cover
17

Development of the 5-exo-dig/Prins Reaction and Efforts towards the Total Synthesis of (±)-Magellanine

Bétournay, Geneviève L. January 2012 (has links)
Gold catalysis has attracted much attention within the chemical community in recent years, and its importance as a synthetic tool has only started to be uncovered. This thesis describes the development of a gold(I) catalyzed transformation and its application to the synthesis of a structurally unique Lycopodium alkaloid, Magellanine. Although there have been a few reports on the synthesis of the magellanane core to date, the approach described herein would represent a new and efficient strategy to construct the angularly fused tetracyclic core. The 5 exo dig/Prins reaction that would be the key step of the synthesis was first developed and studied on a model substrate, enabling the verification of the hypothesis that this transformation could indeed form the A and B rings of Magellanine and be applied to its synthesis. This reaction formed the tricyclic products in good yields and in good exo:endo ratios. The synthesis of Magellanine was undertaken, but problems of isomerization prevented the synthesis of the desired 5 exo dig/Prins substrate, which contained the C and D rings of Magellanine with a cis relationship at the ring junction. However, an almost identical substrate, save for a trans configuration between the C and D rings instead of the cis configuration, was prepared and served in further establishing the applicability of this methodology to the synthesis of Magellanine by successfully undergoing the 5-exo-dig/Prins reaction and generating the tetracyclic products. Studies of the steps following the key transformation were performed on the model substrate, allowing for the evaluation of these steps prior to their use in the synthesis. The results of the studies indicate a possible need to revisit the order in which the steps should be carried out. Promising solutions to the different obstacle encountered during the work are presented, demonstrating how the synthesis of Magellanine through a route featuring the 5-exo-dig/Prins cyclization is attainable.
18

Renovace stokové sítě CIPP metodami / Renovation of sewer network with CIPP methods

Holeš, Petr January 2014 (has links)
Diploma thesis makes a summary of today’s state of CIPP methods designed for sewer relining. Thesis presents classification of CIPP methods between other NO-DIG technologies. Then CIPP methods are divided into groups according to the material used for the liner, applied resin, installation method and curing method. Designing of the CIPP liner used for sewer renovation is also part of this diploma thesis. The result of the theoretical part of this work is a table, which states suitability of particular methods for use in a sewer of specific technical properties. Practical part of bachelor’s thesis is dealing with the analysis of defects of an existing sewer in the city Přerov. Analysis was done due to the camera examination provided by the company Wombat s.r.o. Later the table developed in theoretical part was applied, and then the suitability of use of all parameters of CIPP liners was commented. At the end the plan of works is designed, with the plan for pumping of water included.
19

En egen identitet : En komparativ studie av Amanda Svenssons Hey Dolly, Välkommen till den här världen och Allt det där jag sa till dig var sant

Andersson, Anna January 2016 (has links)
This essay is a study of three fiction novels by the Swedish author Amanda Svensson: Hey Dolly (2008), Välkommen till den här världen (2011) and Allt det där jag sa till dig var sant (2014). A unified theme for the novels is identity making where the three young female protagonists try different identities and explore who they are. The aim of this study is therefore to investigate in which ways the protagonists explore their identities and how this is expressed. Gender theory and genre theory are used when analyzing the characters in the novels. In the analysis it becomes clear that the protagonists explore their identities in different ways. The three young women are aware of that they live in a society in which male and female gender stereotypes exist. In some cases they adjust to the gender roles but in many cases they also observe the gender stereotypes and problematize them. Therefore the protagonists sometimes differ from how a stereotype woman is portrayed.
20

Methodology for the synthesis of NP25302 and other bioactive natural products

Stevens, Kiri January 2011 (has links)
Total synthesis of the pyrrolizidine alkaloid NP25302: (+)-NP25302 is an unusual vinylogous urea containing pyrrolizidine alkaloid shown to exhibit cell adhesion inhibition. It was envisaged that this natural product could be accessed by a novel 5-endo-dig cyclisation to construct the pyrrolizidine core, and a Curtius rearrangement to install the vinylogous urea motif. This methodology was first tested on a model system, furnishing nor-NP25302 from L-proline in 12 steps and 9% overall yield. The total synthesis of (±)-NP25302 was completed in 9 steps and 26% overall yield from ethyl 2-nitropropionate using similar methodology. Studies into the stereospecificity of the Au(I)-catalysed cyclisation of monoallylic diols: During the synthesis of (+)-isoaltholactone in the Robertson group, the key Au(I)-catalysed cyclisation was observed to occur with some stereospecificity. Further investigations were therefore conducted into the stereochemical outcome of this reaction using stereodefined allylic alcohols, and from the combined results a mnemonic was proposed to predict the stereochemistry of the products of this reaction. Studies into the total synthesis of ascospiroketals A and B: Investigations were conducted into the total synthesis of the recently isolated natural products ascospiroketals A and B. A second generation synthesis was used to construct advanced intermediates 1 and 2.

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