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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.
41

Structure et réactivité d'ylures de triazolium applications à la synthèse des dérivés isoindoliques /

Surpateanu, Georgiana. Vergoten, Gérard. January 2000 (has links) (PDF)
Thèse doctorat : Instrumentation et analyses avancées : Lille 1 : 2000. / Résumé en français et en anglais. Bibliogr. p. 173-189.
42

Pharmacological evaluation of the NO/cGMP signalling system /

Asplund Persson, Anna K., January 2005 (has links) (PDF)
Diss. (sammanfattning) Linköping : Linköpings universitet, 2005. / Härtill 4 uppsatser.
43

Avaliação da atividade antimicrobiana e citotóxica de novos compostos triazólicos

Silva, Iara Filardi da 18 May 2012 (has links)
Made available in DSpace on 2015-04-11T13:54:19Z (GMT). No. of bitstreams: 1 Iara Filardi da Silva.pdf: 2120501 bytes, checksum: 9273a177032b8356a33154587a462474 (MD5) Previous issue date: 2012-05-18 / FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas / The search for new antimicrobial agents is necessary due to the emergence of resistant microorganisms and fatal opportunistic infections associated with the acquired immunodeficiency syndrome (AIDS), cancer chemotherapy and transplantation. The triazole compounds are one of the most studied heterocyclic systems today and have attracted much interest because they have a wide range of applications, ranging from use as explosives, even as agrochemicals and pharmaceuticals. This study aimed to evaluate the antimicrobial activity of synthetic 1,2,3 triazole compounds in yeasts Candida sp, the bacteria Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus faecalis and filamentous fungi Microsporum canis, Trichophyton rubrum and Aspergillus niger using the technique of microdilution and evaluate the cytotoxicity of the compounds showed antimicrobial activity tests for cell viability in fibroblasts NIH3T, hemolytic potential in human blood and anticoagulant activity in human plasma. Of all the compounds screened, four showed good anti-candida (MIC 0.25 to 0.06 mmol/L). These same compounds also show activity for M. canis (MIC 50-100 mg/mL), T. rubrum (25 MIC 6.25 mg/mL) and A. niger (MIC 100 mg/mL). None of the compounds tested showed antibacterial activity for P. aeruginosa, S. aureus and E. faecalis. All compounds showed antifungal activity showed low cytotoxicity for the tests analyzed. From screening of 90 new compounds were identified four 1,2,3 triazole which may have potential for the development of new drugs with antifungal activity / A pesquisa de novos agentes antimicrobianos se faz necessária devido ao surgimento de microrganismos resistentes e de infecções oportunistas fatais, associadas à síndrome da imunodeficiência adquirida (SIDA), quimioterapia antineoplásica e transplantes. Os compostos triazólicos são um dos sistemas heterocíclicos mais estudados atualmente e têm despertado muito interesse pelo fato de possuírem um vasto campo de aplicações, que vão desde o uso como explosivos, até como agroquímicos e fármacos. O presente trabalho teve como objetivo avaliar a atividade antimicrobiana de compostos triazólicos sintéticos em leveduras do gênero Candida sp, nas bactérias Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus faecalis e nos fungos filamentosos Microsporum canis, Aspergillus niger e Trichophyton rubrum através da técnica de microdiluição em caldo e avaliar a citotoxicidade dos compostos que apresentaram atividade antimicrobiana pelos testes de viabilidade celular em fibroblastos murinos NIH3T3, potencial hemolítico e atividade anticoagulante. Dos 90 compostos triados, quatro apresentaram significativa atividade anti-candida (MIC 0,25-0,06 mmol/L). Esses mesmos compostos também apresentaram atividade para M. canis (MIC 50-100 mg/mL), T. rubrum (MIC 6.25- 25 mg/mL) e para A. niger (MIC 100 mg/mL). Nenhum dos compostos testados apresentou atividade anti-bacteriana para P. aeruginosa, S. aureus e E. faecalis. Todos os compostos que apresentaram atividade antifúngica apresentaram baixa citotoxicidade para os testes analisados. A partir do screening de 90 novos compostos triazólicos foram identificados quatro os quais podem ter potencial para o desenvolvimento de novos fármacos com atividade antifúngica
44

S?ntese de compostos cumar?nicos-1,2,3-triaz?is an?logos ao Novobiocin planejados como inibidores da HSP90

FRANCO, Daiana de Fatima Portella 27 August 2015 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-07-12T19:09:00Z No. of bitstreams: 1 2015 - Daiana de Fatima Portella Franco.pdf: 10785257 bytes, checksum: 88b5e7659327980d96446ec26df23a79 (MD5) / Made available in DSpace on 2017-07-12T19:09:00Z (GMT). No. of bitstreams: 1 2015 - Daiana de Fatima Portella Franco.pdf: 10785257 bytes, checksum: 88b5e7659327980d96446ec26df23a79 (MD5) Previous issue date: 2015-08-27 / CAPES / CNPq / FAPERJ / Cancer is a generic term related to more than 100 types of diseases which resemble each other by their disorganized cellular growth. HSP90 are ATP-dependent chaperones responsible for the activation and stabilization of more than 200 proteins. Most of these proteins are connected to cancer and need HSP90 to execute their activities. Thus, HSP90 inhibitors may indirect inhibit plenty oncogenic proteins. According to the literature, there are N-terminal and C-terminal domains, nevertheless, C-terminal inhibitors present more advantages. Then, the advancement of C-terminal inhibitors represents an applicable alternative and an intense field of study. Novobiocin is the first compound identified as C-terminal domain inhibitor. Nowadays, Novobiocin analogues have been synthesized, besides its structure-activity relationship elucidated in order to develop more potents analogues. For that reason, the goal of this project is to obtain 2 analogue series of Novobiocin. The scheme of these series was based on maintaining the coumaniric part presented on Novobiocin: isosteric replacement of the amide group that binds coumarin to the 4-hydroxy-3-(3-methylbut-2-yl)-benzamide, by the [1,2,3]-triazole; and exploration of methyl groups (AN1) and hydroxyl (AN2) in substitution of subunit noviose. AN1 series (76a-g) and AN2 (77a-g) were synthesized from the followed reactions: 7-hydroxy-coumarine o-methylation (83); 7-methoxy-coumarine 3-bromation (82); Sonogashira cross-coupling from 3-bromo-7-R-coumarine (81a-b); 7-R-3-((trimethylsilyl)ethynyl-coumarine trimethylsilyl deprotection (88a-b); and lastly, synthesis of the triazole ring, through cicloaddition reaction, 1,3-dipolar catalysed by copper (CuAAc), using 3-ethynyl-7-R-coumarine (80a-b) and aromatic azides. It is worth taking into consideration that 3-bromo-7-R-coumarine (81b) was obtained from the key compound, 3-bromo-7-R-methoxy-coumarine (81a) by o-demethylation reaction. 12 compounds were obtained (76a-g) and 8 of them (76a-b, 77d) were nicely purified and then, characterized by spectroscopic techniques (IR, 1H and 13C NMR). The ?one-pot? synthesis of 7-methoxy-3-(1H-1,2,3-triazole-4-phenyl)-coumarine 76b from 88a compound (Yield=86%) was more efficient than the one realized in two steps (global yield=47,2%). Results are potential and satisfactory, moreover there is no citation in any literature about biological activities of the synthesized compounds. Continuing this work, the pure compounds (76a-b, 77d) will be tested on breast cancer cell lines SkBr3 and MCF-7. / O c?ncer ? um termo gen?rico que se refere a um conjunto de mais de 100 tipos de doen?as, as quais se assemelham pelo crescimento celular desordenado. As HSP90 s?o chaperonas ATP-dependente respons?veis pela ativa??o e estabiliza??o de mais de 200 prote?nas. Muitas destas prote?nas s?o relacionadas ao c?ncer e necessitam da HSP90 para exercerem suas atividades. Assim, inibidores da HSP90 s?o promissores, pois possibilitam inibir de maneira indireta v?rias prote?nas oncog?nicas simultaneamente. S?o descritos inibidores dos dom?nios N-terminal e C-terminal, sendo estes mais vantajoso que aqueles. O Novobiocin foi o primeiro composto identificado como inibidor do dom?nio C-terminal da HSP90. Atualmente, diversos an?logos ao Novobiocin tem sido sintetizados, afim de se estabelecer a rela??o estrutura-atividade, objetivando desenvolver an?logos mais potentes. Assim, o objetivo deste trabalho foi obter duas s?ries an?logas ao Novobiocin. O planejamento das s?ries foi baseado na manuten??o do n?cleo cumar?nico presente no Novobiocin; troca isost?rica do grupo amida, que liga a cumarina ao anel 4-hidroxi-3-(3-metillbut-2-il)-benzamida, pelo anel [1,2,3]-triazol; e explora??o de grupos metoxila (AN1) e hidroxila (AN2) em substitui??o ? subunidade noviose. As s?ries AN1 (76a-g) e AN2 (77a-g) foram sintetizadas a partir das rea??es de: O-metila??o da 7-hidroxi-cumarina (83); broma??o da posi??o 3 da 7-met?xi-cumarina (82); rea??o de acoplamento cruzado de Sonogashira, a partir da 3-bromo-7-R-cumarina (81a-b); desprote??o do grupamento trimetilsilila da 7-R-3-((trimetilsilil)etenil)-cumarina (88a-b); e por fim, s?ntese do anel triaz?lico, atrav?s da rea??o de cicloadi??o 1,3-dipolar catalisada por cobre (CuAAc), utilizando 3-etenil-7-R-cumarina (80a-b) e azidas arom?ticas. Vale ressaltar que, a 3-bromo-7-hidr?xi-cumarina (81b) foi obtida a partir do composto chave, 3-bromo-7-met?xi-cumarina (81a) via rea??o de O-demetila??o. Obteve-se 12 compostos (76a-g e 77a-g) sendo que 8 (76a-b, 77d) foram, satisfatoriamente, purificados e, ent?o, caracterizados por t?cnicas espectrosc?picas (IV, RMN H e C). Tamb?m foi constatado que a s?ntese ?one-pot? de 7-metoxi-3-(1H-1,2,3-triazol-4-fenil)-cumarina 76b partir do composto 88a (R=86%) foi mais eficiente que a realizada em duas etapas, desilina??o/CuAAc (Rglobal= 47,2%). Os resultados s?o satisfat?rios e promissores, al?m disso n?o h? na literatura descri??o das atividades biol?gica dos compostos sintetizados. Em continua??o a este trabalho, os compostos puros (76a-b, 77d) ser?o devidamente ensaiados frente a c?lulas das linhagens de c?ncer de mama SkBr3 e MCF-7.
45

Synthesis of Nitrogen-Containing Compounds from Terminal Alkynes and Sulfonyl Azides via N-Sulfonyl-1,2,3-triazoles / N-スルホニル-l, 2, 3- トリアゾールを経由する末端アルキンとスルホニルアジドからの含窒素化合物の合成法

Funakoshi, Yuuta 25 September 2017 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第20713号 / 工博第4410号 / 新制||工||1685(附属図書館) / 京都大学大学院工学研究科合成・生物科学専攻 / (主査)教授 村上 正浩, 教授 杉野目 道紀, 教授 松原 誠二郎 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
46

Development of New Synthetic Transformations of N-Sulfony1-1,2,3-triazoles / N-スルホニル-1,2,3-トリアゾール類の新しい分子変換反応の開発

Zhao, Qiang 25 March 2019 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21796号 / 工博第4613号 / 新制||工||1718(附属図書館) / 京都大学大学院工学研究科合成・生物化学専攻 / (主査)教授 村上 正浩, 教授 松田 建児, 教授 中尾 佳亮 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
47

Riluzole–Triazole Hybrids as Novel Chemical Probes for Neuroprotection in Amyotrophic Lateral Sclerosis

Sweeney, J.B., Rattray, Marcus, Pugh, V., Powell, L.A. 30 May 2018 (has links)
Yes / Despite intense attention from biomedical and chemical researchers, there are few approved treatments for amyotrophic lateral sclerosis (ALS), with only riluzole (Rilutek) and edaravone (Radicava) currently available to patients. Moreover, the mechanistic basis of the activity of these drugs is currently not well-defined, limiting the ability to design new medicines for ALS. This Letter describes the synthesis of triazole-containing riluzole analogues, and their testing in a novel neuroprotective assay. Seven compounds were identified as having neuroprotective activity, with two compounds having similar activity to riluzole.
48

Novel Strategies Towards Condenced Triazoles, Ferrocene Aminoacids, Conjugates And Selenosulfides

Sudhir, V Sai 11 1900 (has links)
Chapter 1: Facile entry into triazole fused tetrahydropyrazinones from amines and amino acids. In this chapter, A practical and high yielding regioselective synthesis of several new, enantiopure 4,5,6,7-tetrahydro[1,2,3]triazolo[1,5-a]pyrazin-6-ones is described starting from primary amines in a three step reaction sequence (alkylation, acylation, one-pot displacement with azide followed by cycloaddition) employing constrained intramolecular ‘click’ reaction as the key step. The method obviates chromatographic purification of products. This methodology was also extended to the synthesis of diverse triazole fused tetrahydropyrazinones derived from amino acids. The scope of this methodology was extended by varying the alkyl as well as acyl components which furnished other triazole fused novel heterocycles. Chapter 2: Facile entry into triazole fused heterocycles via sulfamidate derived azido-alkynes. Direct synthesis of condensed triazoles from diverse sulfamidates by ring opening of sulfamidates with sodium azide followed by one-pot propargylation and cycloaddtion furnished title compounds. The methodogy in general has been demonstrated on diverse sulfamidates derived from amino acids, amino acid derivatives to obtain a variety of triazole fused scaffolds. In one example, a condensed triazole containing amino acid has been synthesized by ring opening of a sulfamidate derivative with propargyl amine. This methodology has also been extended to the synthesis of condensed triazoles derived from D-glucose. Chapter 3: ‘Click Chemistry’ Inspired Synthesis of Novel Ferrocene-Amino acid, Peptide Conjugates. In this chapter synthesis of a wide range of ferrocene-amino acid and peptide conjugates in excellent yield is presented. Conjugation is established via copper catalyzed Huisgen 1,3-dipolar cycloaddition. Two complementary strategies were employed for conjugation, one involving cycloaddition of amino acid derived azides with ethynyl ferrocene and the other involving cycloaddition between amino acid derived alkynes with ferrocene derived azides. Labeling of amino acids at multiple sites with ferrocene is discussed. A new route to 1, 1’ unsymmetrically substituted ferrocene conjugates is reported. A novel ferrocenophane is accessed via bimolecular condensation of amino acid derived bis alkyne with azide. The electrochemical behavior of a few selected ferrocene conjugates has been studied by cyclic voltammetry. Chapter 4: Click Chemistry inspired Synthesis of Ferrocene Amino acids and other derivatives. This work reports the synthesis of a wide range of ferrocenyl-amino acids and other derivatives in excellent yield. Diverse amino acid containing azides were synthesized and ligated to ferrocene employing click reaction to access ferrocenyl amino acids. Chiral alcohols, esters, diols amines containing azido group were tagged to ferrocene via click reaction to generateferrocene derived chiral derivatives. A novel strategy for direct incorporation of ferrocene into a peptide and a new route to 1, 1’ disubstituted ferrocene amino acid derivative are reported. Synthesis of mono and disubstituted ferrocene derivatives employing ferrocene derived azides is also described. Chapter 5: Convenient synthesis of Ferrocene Conjugates mediated by Benzyltriethylammonium Tetrathiomolybdate in a multi-step tandem process. The synthesis of a wide range of ferrocene derived sulfur linked mono and disubstituted Michael adducts and conjugates mediated by benzyltriethylammonium tetrathiomolybdate in a tandem process is reported. New route to access acryloyl ferrocene and 1,1’-bis acryloyl ferrocene is discussed. Conjugation of amino acids to ferrocene is established via their Nand Ctermini and also via side chain employing conjugate addition as key step to furnish monovalent and divalent conjugates. This methodology has also been extended to access several ferrocene carbohydrate conjugates. The electrochemical behavior of a few selected ferrocene conjugates has been studied by cyclic voltammetry. Finally, 1,1’-bis acryloyl ruthenocene was synthesized and it was utilized for the preparation of ruthenocene-carbohydrate conjugate in good yield. Chapter 6: Formation of Intramolecular S-Se bond mediated by tetrathiomolybdate. In this chapter, we have disclosed our preliminary results on reactivity of tetrathiomolybdate towards compounds containing both thiocyanate and selenocyanate functionalities. Several such compounds have been synthesized from the corresponding dibromides in two steps. We have observed selective reductive dimerization of selenocyanate over thiocyanate. In all the cases we also obtained seleno-sulfides via disulfide diselenide exchange reaction upon addition of excess tetrathiomolybdate. In the case of substrates on benzene scaffold, disulfide and diselenide bridged macrocycles were obtained apart from seleno sulfides whereas in the case of ferrocene derived substrates, formation of macrocycles was not observed. A tentative mechanism for the formation of these novel seleno sulfides is also discussed.(For structural formula pl see the pdf file)
49

Etudes sur la catalyse de la réaction de Huisgen et nouvelles applications synthétiques

Elamari, Hichem 25 May 2011 (has links) (PDF)
Au cours de ce travail, nous avons effectué une étude méthodologique pour la préparation de banques de triazoles, en utilisant la réaction de la chimie " clic ". Ces études ont démontré que la réaction entre un alcyne vrai activé et un azoture est possible dans les conditions sans solvant et sans catalyseur pour conduire un mélange d'isomères 1,4 et 1,5 avec un rendement moyen de 76%. Nous avons remarqué que l'addition des métaux (SiO2, MgCl2, Al2O3, FeCl3 et CuCl2) permettait d'améliorer les rendements des réactions, et on a observé que la silice est la meilleur catalyseur, alors que la catalyse au cuivre (I) donne une sélectivité complète pour l'isomère 1,4. Ce résultat est bien confirmé par l'étude de la régiosélectivité qui montre que les molécules contenant deux types d'alcynes (activé et non activé) peuvent êtres fonctionnalisés séquentiellement et sélectivement. Nous avons aussi préparé les bis-triazoles en deux étapes : la première sur l'alcyne activé sans catalyseur et la deuxième étape se fait sur l'alcyne non activé par catalyse au cuivre (I), ce qui permet de dire que les alcynes terminaux portant un groupement carbonyle en  de la triple liaison sont beaucoup plus réactifs.Nous avons également pu étendre l'application de la catalyse supportée dans la réaction de Huisgen dans les domaines de la synthèse de dérivés de produits naturels et d'éthers couronne. En utilisant la synthèse classique et en flux continu, nous avons pu préparer des structures originales dérivées de l'acide quinique porteuse de cycles triazoliques. Ces composés seront testés pour leur activité biologique. Nous avons également entrepris la synthèse de dérivés nouveaux d'éthers couronnes azotes afin d'incorporer à ces structures des bras contenant un ou deux noyaux triazoles. L'obtention de ces substances permettra d'ouvrir l'étude de leur propriétés complexantes dans l'avenir
50

Aproximacions sintètiques per a la preparació en dissolució i fase sòlida de llibreries de sistemes herocíclics de 5 membres amb elevada diversitat molecular. Síntesi d'imidazolones, triazoles i imidazoxazoles

Heras i Corominas, Montserrat 27 July 1999 (has links)
According to a strategy based on an Aza-Wittig reaction type, an efficient methodology in solution toward the synthesis of libraries of 2-aminoimidazolones with high molecular diversity has been developed. The strategy is readily adapted to the solid support. The regioselectivity in the heterocyclisation reaction between the corresponding carbodiimides and different primary amines for the synthesis of 2-aminoimidazolones has been studied. A correlation between the regioisomer obtained and the stereoelectronic properties of the primary amines used was stablished. The structural elucidation of there 2-aminoimidazolones was unambiguously established based on spectroscopic properties and X-Ray diffraction data / D’acord amb una estratègia basada en la reacció Aza-Wittig, s’ha desenvolupat una metodologia eficient en dissolució, fàcilment adaptable a la síntesi en fase sòlida per l’obtenció de llibreries de 2-aminoimidazolones tipus 2 i 3 amb elevada diversitat molecular. S’ha estudiat la regioselectivitat en les reaccions d’heterociclació per l’obtenció de 2-aminoimidazolones a partir de les corresponents carbodiimides 1 i diferents amines primàries, relacionant els regioisòmers obtinguts amb les propietats estereoelectròniques de les diferents amines utilitzades. Les estructures de 2-aminoimidazolones obtingudes s’han determinat inequívocament en base a les seves dades espectroscòpiques i per difracció de raigs X

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