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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.
161

[en] SYNTHESIS OF THE 11A-N-ARYLSULFONIL-TETRAHYDRO-5H-BENZO[A]CARBAZOLES WITH ANTITUMORAL ACTIVITY / [pt] SÍNTESE DE 11A-N-ARILSULFONIL-TETRAHIDRO-5H-BENZO[A]CARBAZÓIS COM AÇÃO ANTITUMORAL

JOSEANE ALVES MENDES 11 April 2017 (has links)
[pt] Este trabalho apresenta a síntese e caracterização de 11-tosil-6,6a,11, 11-tetraidro-5H-benzo[a]carbazois análogos ao LQB223, um composto previamente sintetizado em nosso grupo de pesquisa que tem ação anticâncer e antileishmanial in vitro e ação antimalarial in vitro e in vivo. A etapa chave da reação para a obtenção dos 5-metoxi-11a-N-arilsulfonil-tetrahidro-5H-benzo[a]carbazol (97a), 6-metoxi-11a-N-arilsulfonil-tetrahidro-5H-benzo[a]carbazol (97b) e 7-metoxi-11a-N-arilsulfonil-tetrahidro-5H-benzo[a]carbazol (97c) envolve uma reação de aza-arilação de Heck catalisada por paládio na presença de carbonato de prata e acetona entre o N-tosil-o-iodoanilina (55b) e dihidronaftalenos substituídos (100a, 100b, e 100c), preparados previamente a partir de tetralonas comerciais (84a, 84b, 84c). Os compostos 5-hidroxi-11a-N-arilsulfonil-tetrahidro-5H-benzo[a]carbazol (98a), 6-hidroxi-11a-N-arilsulfonil-tetrahidro-5H-benzo[a]carbazol (98b) e o 7-hidroxi-11a-N-arilsulfonil-tetrahidro-5H--benzo[a]carbazol (98c) foram obtidos através da desproteção das metoxilas com BBr3 em rendimentos quantitativos. Todos os compostos foram avaliados quanto a ação anticâncer em linhagens de leucemia que apesentam o fenótipo MDR lucena e FEPS e em linhagem de leucemia K562 e nas linhagens de câncer de mama MCF-7, que expressa o receptor de estrogênio, e MDA-MD231.Dentre os compostos preparados, o composto 6-metoxi-11a-N-arilsulfonil-tetrahidro-5H-benzo[a]carbazol (97b) foi tão ativo quanto o LQB223 frente a ação antileucêmica nas linhagens K562, lucena e FEPS, entretanto foi mais eficaz que o LQB223 nas linhagens de MCF-7 (IC50 igual 5,93 mais ou menos 3,58 MiM) e MDA-MD231 (IC50 igual 8,29 mais ou menos 2,08 MiM), apresentando um nível baixo de toxicidade para as células sadias. Por outro lado, o composto 6-hidroxi-11a-N-arilsulfonil-tetrahidro-5H-benzo[a]carbazol (98b), apesar de ser muito ativo em linhagens de câncer mama, possui um alto nível de toxicidade para células sadias e composto 7-hidroxi-11a-N-arilsulfonil-tetrahidro-5H-benzo[a]carbazol (98c) foi eficaz em MDA-MD231 (IC50 igual 4,84) porém ainda não foi avaliado quanto a toxicidade em células sadias. Os dados sugerem que os compostos oxigenados 97b e 98c direciona a ação para o câncer de mama. / [en] This work describes the synthesis and characterization of the 11a-N-arylsulfonil-tetrahydro-5H-benzo[a]carbazoles analogous to LQB223, a previously synthesized compound by our research group that has anti-cancer and antileishmanial activity in vitro and antimalarial activity in vitro and in vivo. The key step of the reaction for obtaining the 5-methoxy-11a-N-arylsulfonil-tetrahydro-5H-benzo[a]carbazole (97a), 6-methoxy-11a-N-arylsulfonil-tetrahydro-5H-benzo[a]carbazole (97b) and 7-methoxy-11a-N-arylsulfonil-tetrahydro-5H-benzo[a]carbazole (97c) is the palladium catalyzed Heck aza-arylation reaction in the presence of silver carbonate and acetone from N-tosyl-o-iodoaniline (55b) and substituted dihydronaphthalenes (100a, 100b and 100c), previously prepared from commercial tetralones (84a, 84b and 84c). The compounds 5-hydroxy-11a-N-arylsulfonil-tetrahydro-5H-benzo[a]carbazole (98a), 6-hydroxy-11a-N-arylsulfonil-tetrahydro-5H-benzo[a]carbazole (98b) and 7-hydroxy-11a-N-arylsulfonil-tetrahydro-5H-benzo[a]carbazole (98c) were obtained by deprotection with BBr3 in yields quantitative. All compounds were evaluated for anticancer activity in K562, FEPS and Lucena leukemia cell lines, which exhibit the MDR phenotype, and in breast cancer cell lines MCF-7, which expresses the estrogen receptor, and MDA-MD231.Among the compounds prepared, the compound 97b is as active as LQB223 for the antileukemic activity on K562 lines, and Lucena FEPs, however it is more effective than the LQB223 in MCF-7 (IC50 equal 5.93 plus/minus 3.58 MiM) and MDA-MD231 (IC50 equal 8.29 plus/minus 2.08 uM) breast cancer lines, with low level of toxicity to healthy cells. The compound 98b presents similar activity to 97b but is toxic. The compound 98c is effective in MDA-MD231 (IC50 equal 4,84) but, level of toxicity to healthy cells was not test yet. The reports suggest that the oxygenation pattern in the 3 position directs to the anticancer activity to the breast cancer lines.
162

Compuestos de Paladio soportados en distintos materiales. Aplicación en Catálisis heterogénea

Leyva Perez, Antonio 06 May 2008 (has links)
Leyva Perez, A. (2005). Compuestos de Paladio soportados en distintos materiales. Aplicación en Catálisis heterogénea [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/1839 / Palancia
163

Synthese von Ferrocenylphosphan- und Ferrocenyldiphosphan-basierenden Übergangsmetallkomplexen sowie deren Verwendung in der homogenen Katalyse

Schreiner, Claus 29 January 2010 (has links)
Im Rahmen der vorliegenden Arbeit wurden Studien zur Modifizierung und Immobilisierung mono- und bidentater Ferrocenylphosphane an Carbosilan-Trägermolekülen durchgeführt. Erstere wurden in die entsprechenden (p-Cymen)RuCl2-Komplexe überführt und als (Prä)Katalysatoren für die Oxopropylester-Synthese eingesetzt. Dabei wurden sowohl der Einfluss unterschiedlicher Ferrocenylphosphan-Liganden als auch der Effekt der Immobilisierung auf die katalytische Umsetzung herausgearbeitet. Im Weiteren konnte eine neuartige Klasse funktionalisierter zweizähniger Diphosphane des dppf-Typs erschlossen und ihre Identität eindeutig belegt werden. Geeignete Vertreter dieser Verbindungsklasse wurden wie die entsprechenden monodentaten Ferrocenylphosphane an Carbosilan-Grundgerüste angebunden und, nach Überführung in die entsprechenden PdCl2-Komplexe, als (Prä)Katalysatoren für Heck-Kreuzkupplungsreaktionen verwendet. Auch hier konnte der Effekt der Immobilisierung sowie der Einfluss der unterschiedlichen Phosphanliganden auf die katalytische Reaktion ermittelt werden. Abschließend wurden Untersuchungen zur Verwendung monomerer Mesitylphosphan-substituierter Ferrocenyldiphosphane als Liganden in der Heck-Reaktion unterschiedlicher Arylhalogenide mit Acrylaten zu den entsprechenden Zimtsäureestern durchgeführt. Zur Bestimmung der katalytischen Leistungsfähigkeit wurde neben Reaktionstemperaturen und Katalysatorkonzentrationen insbesondere die verwendete Halogenkomponente variiert.
164

Stereoselective Nucleophilic Additions to Aldehydes and Synthesis of α-Amino-β- Hydroxy-Esters

Danielsson, Jakob January 2012 (has links)
This thesis deals with the development of new reaction methodology as well as stereochemical investigations. The first part concerns the investigation of 1,2- and merged 1,2- and 1,3- asymmetric induction in Mukaiyama aldol additions to α-heteroatom and α,β- heteroatom substituted aldehydes respectively. In particular, the unexpected 1,2-syn selectivity obtained in the addition of sterically hindered nucleophiles to α-chloroaldehydes is examined, and an explanation for the observed stereochemical trends is proposed. The second part describes the development of a novel entry to α-amino-β- hydroxy esters by a 1,3-dipolar cycloaddition reaction of aldehydes and azomethine ylides, generated by thermolysis of aziridines. The third part deals with our efforts to develop a novel entry to vicinal all- carbon quaternary centers, based on an intramolecular domino Heck- carbonylation reaction using tetrasubstituted olefins. / QC 20120611
165

Novel Cinchona Alkoloid Derived Ammonium Salts as Phase-Transfer Catalysts for the Asymmetric Synthesis of Beta-Hydroxy Alpha-Amino Acids Via Aldol Reactions and Total Synthesis of Celogentin C.

Ma, Bing 16 June 2009 (has links) (PDF)
Project I. Cinchona alkaloid-derived quaternary ammonium salts have been successfully used as phase-transfer catalysts, particularly in asymmetric alkylations. Our group applied this type of catalyst in the synthesis of β-hydroxy α-amino acids via aldol reactions and discovered that the Park-Jew catalyst afforded good yields and good enantiomeric excess of the syn diasteromers, but negligible diastereoselectivity. This project was therefore focused on the synthesis of novel cinchonidine-derived catalysts with the Park-Jew catalyst as the lead structure. The C3 position of cinchonidine nucleus was modified to achieve dimers and catalysts possessing electron-deficient alkyne and alkene moieties. Synthesized catalysts were tested in the asymmetric aldol reactions, with some of them yielding improvements relative to the Park-Jew catalyst. Project II. Celogentin C is a natural product that was isolated from the seeds of Celosia argentea by Kobayashi in 2001. It is the most potent inhibitor of the polymerization of tubulin from among the celogentin family. The novel bicyclic octapeptide structure contains unusual linkages between leucine β-carbon and indole C-6 of tryptophan and between tryptophan indole C-2 and imidazole N-1 of histidine. The project culminated in the first total synthesis of celogentin C. Reaction conditions were developed by synthesizing the left-hand ring and the right-hand ring separately, and the total synthesis was accomplished via a left to right strategy. Key transformations in the construction included intermolecular Knoevenagel condensation, radical conjugate addition, macrolactamization, and oxidative coupling.
166

Monomeric, Dimeric and Polymeric Re<sup>I</sup>(CO)<sub>3</sub> Schiff Base Complexes: Synthetic, Spectroscopic, Electrochemical, and Computational Studies

Hasheminasab, S. Abed 09 June 2016 (has links)
No description available.
167

Synthetic Utility of Fused-Cyclobutenes: Synthesis of Medium-Sized Cycloalkenes / 縮環シクロブテンを活用した中員環合成法の開発

Ito, Tomohiro 23 March 2023 (has links)
京都大学 / 新制・課程博士 / 博士(薬科学) / 甲第24544号 / 薬科博第161号 / 新制||薬科||18(附属図書館) / 京都大学大学院薬学研究科薬科学専攻 / (主査)教授 高須 清誠, 教授 竹本 佳司, 教授 大宮 寛久 / 学位規則第4条第1項該当 / Doctor of Pharmaceutical Sciences / Kyoto University / DFAM
168

Palladium-catalyzed heteroannulation of 2-ARYL- 3-IODO-4-(Phenylamino)quinolines and 4-(N,N-allylphenylamino)-2-ARYL-3-iodoquinolines

Lesenyeho, Lehlogonolo Godfrey 09 1900 (has links)
The previously described 2-aryl-4-chloro-3-iodoquinolines were prepared following literature procedure and in turn converted to the corresponding hitherto unknown 2-aryl-3-iodo-4-(phenylamino)quinoline derivatives using aniline in refluxing ethanol. These 2-aryl-3-iodo-4-(phenylamino)quinolines were reacted with allybromide in ethanol at room temperature to afford 4-(N,N-allylphenylamino)-2-aryl-3-iodoquinoline derivatives. The 2-aryl-3-iodo-4-(phenylamino)quinoline and 4-(N,N-allylphenylamino)-2-aryl-3-iodoquinoline derivatives were subjected to metal-catalysed carbon-carbon bond formations. Palladium(0)-copper iodide catalysed Sonogashira cross-coupling of 2-aryl-3-iodo-4-(phenylamino)quinoline with terminal alkynes afforded series of 1,2,4-trisubstituted 1H-pyrrolo[3,2-c]quinolines in a single step operation. On the other hand, the 4-(N,N-allylphenylamino)-2-aryl-3-iodoquinoline derivatives were found to undergo palladium-catalysed intramolecular Heck reaction to yield the corresponding 1,3,4-trisubstituted 1H-pyrrolo[3,2-c]quinolines. All new compounds were characterized by using a combination of NMR (1H and 13C), IR, mass spectroscopic techniques as well as elemental analysis. / Chemistry / MSc. (Chemistry)
169

Contribution à la synthèse totale de la céphalotaxine / Contribution to the total synthesis of cephalotaxine

Quteishat, Laith 12 December 2013 (has links)
Depuis plus de 40 ans des chimistes se sont intéressés à l’extraction, à l’activité biologique et à la synthèse de l’homoharringtonine (HHT), un ester naturel de la céphalotaxine, qui est un puissant antileucémique utilisé pour le traitement des leucémies résistantes aux inhibiteurs de tyrosine kinase. Ces alcaloïdes sont extraits de Cephalotaxus, des conifères originaires du sud de la Chine à croissance extrêmement lente et menacés d’extinction. Leur synthèse est donc nécessaire. L’homoharringtonine utilisée en thérapeutique est obtenue à partir de (-)-céphalotaxine d’origine naturelle, par greffage d’une chaîne latérale acide suivie de purifications longues et coûteuses. L’objectif de ce travail consiste à développer une synthèse concise de la (-)-céphalotaxine, afin de s’affranchir de la ressource naturelle, de ce fait de garantir un approvisionnement d’HHT de qualité constante et de développer des analogues de seconde génération.Les stratégies développées dans ce travail ont consisté à développer une synthèse très concise de la céphalotaxine, d’une part en valorisant un synthon ABC nitrile pour y introduire les deux atomes de carbone manquant au squelette de la céphalotaxine, et d’autre part à améliorer l’accès à une synthon analogue ABC ester pour en étudier la réactivité. Ces travaux ont conduit à décrire un nouveau complexe arène chrome pentacarbonyle analogue de céphalotaxine, une méthode originale et efficace de cyclisation anionique d’imide formant un squelette 3-benzazépine à l’aide d’une nouvelle combinaison de bases, le tert-butylate de potassium et le carbonate de potassium agissant en synergie, et une nouvelle méthode de solvolyse de nitrile aliphatiques ou aromatiques sous micro-ondes qui a été exemplifiée. / For over 40 years, chemists are interested in the extraction, biological activity and synthesis Homoharringtonine (HHT ), a natural cephalotaxine ester, which is a potent antileukemic used therapeutically, especially leukemias resistant against tyrosine kinase inhibitors. These alkaloids are extracted from Cephalotaxus, evergreen trees from southern China having extremely slow growth and are in extinction. Their synthesis is thus necessary. Homoharringtonine used therapeutically is obtained from (-)-cephalotaxine of natural origin, by grafting an acidic side chain followed by lengthy and expensive purifications. The objective of this work is to develop a concise synthesis of (-)-cephalotaxine to get rid of the natural resource, thereby ensuring a supply of constant quality and develop similar second generation of HHT.The strategies developed in this work has been to develop a very concise synthesis of cephalotaxine , firstly by enhancing an ABC nitrile synthon to introduce the two carbon atoms missing to the backbone of cephalotaxine , and secondly to improve access to similar ABC ester synthon to investigate its reactivity. This work led to describe a new arena complex chromium pentacarbonyle cephalotaxine analog, an original and efficient method of anionic cyclization of imide forming a 3-benzazepine skeleton using a new combination of bases , potassium tert -butoxide and potassium carbonate acting synergistically, and a new method of aliphatic or aromatic nitrile solvolysis under microwave which was exemplified.
170

(Ethynyl-)Ferrocenyl Phosphine Palladium Complexes and (Bis-)Phosphinoimidazol(e/ium) Compounds and their Application in Homogeneous Catalysis

Milde, Bianca 19 July 2012 (has links) (PDF)
Die vorliegende Dissertation beschäftigt sich mit der Synthese, der Charakterisierung und der Anwendung neuartiger Phosphane in homogenkatalytischen Reaktionen. Dabei wurden die Ferrocenyl- und Ferrocenylethinylphosphan-Palladium und Ferrocenylethinylphosphan-Ruthenium Komplexe in der Palladium-vermittelten Mizoroki-Heck- und Suzuki-Miyaura-Reaktion sowie der Ruthenium-katalysierten Synthese von β-Oxopropylestern verwendet. Der Schwerpunkt lag dabei auf der Untersuchung des Einflusses der elektronischen und räumlichen Eigenschaften der Phosphanliganden auf die Aktivität und Produktivität der entsprechenden Katalysatoren in den homogenkatalytischen Reaktionen. Weiterhin beschäftigt sich die vorliegende Arbeit mit der Synthese und Charakterisierung von funktionalisierten (Phosphino)Imidazol und (Phosphino)Imidazolium Salzen und deren Anwendung in der Suzuki-Miyaura-Reaktion. Dabei wurde neben der Untersuchung des Einflusses der Position der Phosphanylgruppe und der unterschiedlichen Substituenten ebenfalls die Auswirkung von elektronenziehenden und -schiebenden Gruppen am Phosphanrest untersucht. Die neutralen Mono- und Diphosphane wurden außerdem in der Kreuzkupplung von Arylhalogeniden und in der Synthese räumlich anspruchsvoller Biaryle verwendet. Des Weiteren wurden die (Phosphino)Imidazolium-Salze als Liganden in der Suzuki-Miyaura-Reaktion in ionischen Flüssigkeiten als Reaktionsmedium angewendet, um die Möglichkeit des Recyclings der Katalysatorphase zu untersuchen.

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