Tesi sul tema "Pyrrole"
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1
Scott, Mark Simon. "Pyrrole carbinols". Thesis, University of Cambridge, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.615301.
Testo completo
2
Armitage, Georgina Kate. "The Zav'yalov pyrrole synthesis revisited : some derivatives of 3-hydroxy- and 3-amino-pyrroles". Thesis, University of Huddersfield, 2017. http://eprints.hud.ac.uk/id/eprint/34175/.
Testo completoAbstract (sommario):
The objective of this study was to investigate the acylative-cyclisation-decarboxylation reactions of enamino acids derived from 1,3-difunctional compounds. Remarkably little is known regarding the generality of these variants of the Zav’yalov pyrrole synthesis, despite their considerable scope for the synthesis of functionalised pyrroles. The cyclisation of diethyl 2-(1-carboxyalkylaminomethylene)malonates provided access to a range of 5-(un)substituted-4-acetoxypyrrole-3-carboxylates. However, in some instances the corresponding 4-ethoxypyrrole-3-carboxylates also accounted for up to 20% of the reaction product. 1-Acetyl-4-ethoxy-5-ethylpyrrole-3-carboxylate was characterised by X-ray crystallography. Some of the (aminomethylene)malonates from bifunctional α-amino acids provided anomalous products. For example, the glutamine-derived enamino malonate gave a 5-acetylpyrrolidin-2-one via a Dakin-West-type reaction. The asparagine-enamino malonate cyclised to 4-acetoxy-1-acetyl-5-cyanomethylpyrrole-3-carboxylate probably via an isosuccinimide intermediate. Several mechanisms for the formation of the pyrrole products have been discussed. A 13C-labelling experiment confirmed that the carboxyl function in the starting material is not incorporated in the product. Evidence for the involvement of a 1,3-oxazolium-5-olate (münchnone) accrued from cyclisation of diethyl 2-(1-carboxymethylaminomethylene)malonate with Ac2O in the presence of dimethyl acetylenedicarboxylate which provided a novel 1-alkenylpyrrole, characterised by X-ray crystallography. An alternative pathway supervenes in the Zav’yalov reaction when α,α-disubstitution of the amino acid prevents münchnone and thus pyrrole formation to afford an N-alkenyloxazolidin-5-one. Novel ethyl 4-(di)acetamido-5-(un)substituted-pyrrole-3-carboxylates and the corresponding 3-carbonitriles have been obtained in good yields via the cyclisation of ethyl 2-(1-carboxyalkylaminomethylene)cyanoacetates and (1-carboxyalkylaminomethylene)malononitriles respectively. Evidence for a different cyclisation pathway, in the former, involving intramolecular acylation of the enaminonitrile moiety was observed. Thus, ethyl (2R*,3S*)-1-acetyl-3-cyano-2,4-diacetoxy-5-methyl-2,3-dihydropyrrole-3-carboxylate was characterised by X-ray crystallography. A wide range of novel 2-alkanoyl- and 2-aroyl-3-(1-carboxyalkylamino)acrylonitriles has been obtained via aminomethylenation of β-ketonitriles. The products from their cyclisations (Ac2O-NEt3) were largely independent of the nature of the acyl group but determined by the substituent in the α-amino acid moiety. The 3-(1-carboxy-1-phenylmethylamino)acrylonitriles provided mixtures of 3-acyl-4-(di)acetamido-5-phenylpyrroles in which the 4-acetamido- derivatives predominated. Contrasting behaviour was displayed by the 3-(1-carboxyalkylamino)acrylonitriles derived from alanine, 2-aminobutyric acid and valine in which the cyclisation followed an unexpected course, via enaminone acylation, to the novel 4-acetoxy-1-acetyl-5-alkylpyrrole-3-carbonitriles in high yields. The acylative cyclisation of the 2-acyl-3-(1-carboxymethylamino)acrylonitriles furnished mixtures of pyrroles. In two cases, 3-acetamido-6-aryl-5-cyanopyran-2-ones, generated by a unique cyclisation pathway were isolated. The structure of the 6-phenyl- derivative was confirmed by unambiguous synthesis. The synthesis and acylative cyclisation of (Z)-2-benzoyl-3-(1-carboxyalkylamino)crotononitriles was investigated. Whereas the 3-(1-carboxyethylamino)- derivative provided 4-acetoxy-1-acetyl-2,5-dimethylpyrrole-3-carbonitrile exclusively, the 3-(1-carboxy-1-phenylmethylamino)crotononitrile afforded a mixture of pyrroles. A remarkable minor component was characterised as 4-acetoxy-1-benzoyl-2-methyl-5-phenylpyrrole-3-carbonitrile, the result of sequential [1,5]-benzoyl migrations of a 3H-pyrrole intermediate. The acylative cyclisation of 3-(1-carboxyalkylamino)-2-tosylacrylonitriles provides access to hitherto unknown 3-diacetamido-4-tosyl- and 3-acetamido-4-tosylpyrroles. Cyclisation of 2-(1-carboxyalkylaminomethylene)dibenzoylmethanes offers an excellent, complementary approach to access 5-(un)substituted-3-benzoyl-4-phenylpyrroles, to the existing tosylmethyl isocyanide-based protocols.
3
Watt, Esther Jane. "Poly(pyrrole) based gas sensors". Thesis, Birkbeck (University of London), 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338770.
Testo completo
4
Oussaid, Boualem. "Thiophène, pyrrole : synthèse, conformation, macrocycles". Toulouse 3, 1992. http://www.theses.fr/1992TOU30198.
Testo completoAbstract (sommario):
De nouveaux composes, derives du thiophene ou du pyrrole ont ete synthetises en plusieurs etapes. La conformation de divers composes thiopheniques ou pyrroliques a ete etablie a partir de calculs theoriques, de mesures de moments dipolaires et a partir du couplage stereospecifique a travers cinq liaisons. Quelques macrocycles possedant deux, trois ou quatre restes thiophene ou pyrrole a 18, 20, 30, 34 ou 40 chainons ont ete obtenus par des cyclisations de type 2+2, 3+3 ou 4+4
5
Olivier, Andrew John. "Novel carbene complexes with pyrrole ligands". Diss., Pretoria : [s.n, 2001. http://upetd.up.ac.za/thesis/available/etd-02242006-125303/.
Testo completo
6
Law, Ho. "Synthèse et étude conformationnelle d'hétérocycles soufrés radioprotecteurs : mécanisme réactionnel de formation du cycle thiazolidine : obtention de pyrrole N-éthanethiols". Université Joseph Fourier (Grenoble), 1992. http://www.theses.fr/1992GRE18003.
Testo completo
7
Ekinci, Olcun. "Immobilization Of Glucose Oxidase And Polyphenol Oxidase In Conducting Copolymer Of Pyrrole Functionalized Polystyrene With Pyrrole". Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/2/12607373/index.pdf.
Testo completoAbstract (sommario):
Electrochemical polymerization of pyrrole functionalized polystyrene (PStPy) with pyrrole was carried out in water-sodium dodecyl sulfate solvent-electrolyte couple. Characterization of the resulting copolymer was performed via Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and four probe conductivity measurements. Glucose oxidase and polyphenol oxidase enzymes were immobilized in polypyrrole (PPy) and conducting copolymer of pyrrole functionalized polystyrene with pyrrole (P(PStPy-co-Py). Resulting enzyme electrodes were characterized by kinetic parametersVmax and Km. Behavior of enzyme electrodes upon temperature and pH changes were investigated. Glucose oxidase electrode was used for the determination of glucose in orange juice and polyphenol oxidase electrode was used for the determination of polyphenolic compounds in red wine.
8
Addie, Matthew Stuart. "Synthetic strategies towards pyrrole marine alkaloids". Thesis, University of East Anglia, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267273.
Testo completo
9
Millan, Barrios Enrique Jose. "Synthesis and electrochemistry of pyrrole derivatives". Thesis, University of Southampton, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242418.
Testo completo
10
鍾惠玲 e Chung Wai-ling Margaret Chiu. "The synthesis and reactions of 3, 5-diaryl-2, 2-bis(ethoxycarbonyl)-2H-pyrroles". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1986. http://hub.hku.hk/bib/B31230829.
Testo completo
11
Ngwerume, Simbarashe. "Gold-multifaceted catalysis approach to pyrrole synthesis". Thesis, University of Nottingham, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.604293.
Testo completoAbstract (sommario):
The work presented in this thesis is concerned with the development of novel approaches to the regioselective synthesis of highly substituted pyrroles from simple starting materials. The work detailed herein covers three main research areas: i) A nucleophilic catalysis method for the concise synthesis of substituted NH- or N-Boc-pyrroles, directly from oximes and alkynes; ii) The development of a novel gold-multifaceted catalysis (gold-MFC) method for the regioselective synthesis NH-pyrroles directly from oximes and alkynes, together with a detailed mechanistic investigation which provides an insight into the mechanistic pathway; iii) studies towards an intramolecular macrocyclisation approach towards the synthesis of substituted pyrroles from oximes and alkynes. i) A novel nucleophilic catalysis / microwave irradiation protocol that provides a succinct synthesis of di-, tri, and tetrasubstituted pyrroles in a single operation will be discussed. This one-pot method relies on the use of a nucleophilic catalyst to regioselectively promote the in situ formation of O-vinyloximes from the reaction of oximes and electron deficient alkynes, which after subjection to microwave irradiation afforded the desired pyrroles as single regioisomers. ii) The main body of work in this thesis concerns the development of a novel gold(I)-catalysed method for the regioselective synthesis of highly substituted pyrroles directly from oximes and electron deficient alkynes. This one-pot method was developed via optimisation of two key gold(I)catalysed steps: the formation of O-vinyloximes and rearrangement of preformed O-vinyloximes into the corresponding pyrrole. The cationic gold species was shown to activate multiple mechanistically distinct steps along the reaction pathway and therefore act as a multifaceted catalyst. Notably, this method provides a concise synthesis of di-, tri- and tetrasubstituted pyrroles which contain a functional group handle in the form of an ester at the 3/4-position for further exploitation. The proposed mechanistic pathway is supported by a novel application of the Huisgen cycloaddition click reaction, which was used to probe the relative stability of substituted O-vinyloximes. Further support for the proposed mechanism was provided by high-temperature lH, 2H{lH}, and 13C{lH} NMR experiments. X-ray crystallographic evidence was used to further support the mechanistic hypothesis by confirming the absolute configuration of the oximes, 0- vinyloximes and pyrroles. iii) Preliminary studies into an unprecedented intramolecular pyrrole formation via the direct addition of an oxime to an alkyne are described. ii
12
Marketwala, Nishrin Ismailbhai. "PYRROLE CARBOXAMIDES AS POTENTIAL CARBONIC ANHYDRASE INHIBITORS". Wright State University / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=wright1166468773.
Testo completo
13
Mirebeau, Jean-Hugues. "Synthèse et réactivité de nouveaux complexes pyrrolylrhénium carbonylés". Paris 6, 2009. http://www.theses.fr/2009PA066083.
Testo completoAbstract (sommario):
Les complexes moléculaires des métaux de transition occupent une place de plus en plus importante dans de nombreux domaines de la chimie. Le domaine du vivant ne fait pas exception, grâce à l’apparition de la chimie bioorganométallique. Dans ce cadre, notre laboratoire s’est spécialisé dans l’étude de biomolécules liées à des métaux de transition carbonylés via un lien cyclopentadiènyle. Nous nous sommes proposés de changer ce lien par un pyrrolyle, motif présent dans de nombreuses molécules naturelles. Deux structures ont ainsi été envisagées. La première se compose d’un complexe tricarbonylé du rhénium(I) comportant un ligand pyrrolyle d’hapticité 5. La seconde est basée sur l’association d’un ligand pyrrolyle bidentate, et d’une entité tétracarbonylrhénium(I). La quasi absence de complexes pyrrolylrhénium dans la littérature rend ces structures très intéressantes d’un point de vue fondamental. Pour les obtenir, une étude portant sur la synthèse de pyrroles a été réalisée. Plusieurs dérivés de pyrroles silylés ont, en particulier, été caractérisés pour la première fois et leurs réarrangements en milieu acide a été mis en évidence. Des dérivés de pyrroles substitués en position 2 par une imine chirale ont aussi été synthétisés et ont permis la synthèse des complexes tétracarbonylés du rhénium correspondants. Ces derniers ont été engagés dans des réactions diastéréosélectives d’échange de ligands. Les structures des diastéréoisomères majoritaires et minoritaires ont pu être déterminées par diffraction des rayons X. Ceci constitue une méthode originale d’obtention de complexes octahédriques chiraux.
14
Valderrey, Berciano Virginia. "Calix[4]pyrrole and porphyrin-based molecular assemblies". Doctoral thesis, Universitat Rovira i Virgili, 2013. http://hdl.handle.net/10803/284092.
Testo completoAbstract (sommario):
Esta tesis se centra en el estudio de ensamblajes moleculares de calix[4]pirroles y porfirinas. Las propiedades de interacción y la topología de un bis-calix[4]pirrol macrotriciclo homoditópico han sido empleadas en el desarrollo de tres estrategias generales para el ensamblaje cuantitativo de pseudorotaxanos. En una de estas estrategias, el anión poliatómico de un par iónico es reconocido por el complejo supramolecular que resulta cuando una molécula lineal y neutra enhebra el macrotriciclo. Además, se describe la formación de complejos de dímeros de pares de iones y cuartetes de iones reconocidos por el macrotriciclo a través de un proceso altamente cooperativo. También, se estudia el reconocimiento de sales de tetrabutilamonio derivadas de fullerenos utilizando pinzas moleculares de porfirinas.
Finalmente, se describe la formación de un macrociclo formado por la interacción de bisporfirinas de rodio y bispiridinas. Este macrociclo es usado en la formación de complejos con topología de rotaxano y pseudorotaxano.This thesis is focused on the study of molecular assemblies based on calix[4]pyrroles and porphyrins. The topology and the binding properties of a homoditopic biscalix[4]pyrrole macrotricycle are used to develop three general strategies for the quantitative self-assembly of pseudorotaxane-like complexes. In one strategy, the polyatomic anion of an ion pair is recognized by the supramolecular complex that results when a neutral linear molecule threads the homoditopic macrotricycle. Additionally, the formation of highly stable complexes of ion-pair dimers and quartets of ions by the bis-calix[4]pyrrole receptor through a highly cooperative process is described. Nickel metallated porphyrin tweezers containing calix[4]pyrrole spacers are used in the recognition of the tetrabutylammonium salt of the [6,6]-phenyl-C61-butyric carboxylic acid. Finally, the quantitative self-assembly of a macrocycle formed by the interaction between a rhodium bisporphyrin and a bispyridyl ligand is described. This macrocycle was used in the formation of complexes with [2]pseudorotaxane and [2]rotaxane-like topologies.
15
Galán, Coca Albano. "Molecular containers based on calix[4]pyrrole scaffolds". Doctoral thesis, Universitat Rovira i Virgili, 2016. http://hdl.handle.net/10803/365311.
Testo completoAbstract (sommario):
Aquesta tesi compren la síntesi i l'estudi de diferents contenidors moleculars basats en una estructura macrocíclica de calix[4]pirrol. Els contenidors moleculars poseeixen cavitats polars funcionalitzades ideals per al reconeixement de molècules polars p.ex. anions, N-òxids… La creació de contenidors amb cavitats permanents (cavitants) dona lloc a la formació de complexos termodinàmica i cinèticament molt estables. Les conformacions adoptades en dissolució pels complexos així com la geometria en estat sòlid es discuteixen en detall. També s'aprofundeix en l'estudi de contenidors moleculars amb estructura auto-ensamblada. Es descriu la formació de complexos de co-encapsulació ordenats de clorur i una molècula neutra a l'interior de càpsules moleculars basades en unitats de calixpirrol. En un gran esforç sintètic, es va preparar un contenidor molecular amb topologia de bis[2]catenà format per dos hemisferis de calixpirrol i calixarè units mecànicament. La cavitat anisòtropa va permetre la co-encapsulació de N-òxids petits amb una molècula de dissolvent. La gran estabilitat cinètica dels complexos formats va permetre l'estabilització d'un N-òxid inestable. L'estabilitat termodinàmica del complex supramolecular va ser relacionat amb la cinètica de descomposició de l'N-òxid observat mitjançant els models cinètics.
Finalment, s'estudia la sintesí i propietats de contenidors moleculars amb estructura covalent. La preparació de carcerands formats per la unió (Hay coupling) de dues unitats de tetra-alquinil calixpirrol va donar lloc a la inesperada formació de tetràmers amb estructura anàloga a un nus de vuit. L'ensamblatge de càpsules covalents dinàmiques amb enllaços reversibles del tipus imina també va ser estudiat emprant un tetra-formil calixpirrol com esquelet. En ambdos casos, la presència de una molècula plantilla que preorganitzi el sistema es fonamental per a dur a terme una síntesi eficient dels contenidors.Esta tesis comprende la síntesis y el estudio de diferentes contenedores moleculares basados en una estructura macrocíclica de calix[4]pirrol. Los contenedores moleculares poseen cavidades polares funcionalizadas ideales para el reconocimiento de moléculas polares i.e. aniones, N-oxidos… La creación de contenedores con cavidades permanentes (cavitandos) da lugar a la formación de complejos termodinámica y cinéticamente muy estables. Las conformaciones adoptadas en disolución por los complejos así como la geometría en estado sólido se discuten en detalle. También se profundizó en el estudio de contenedores moleculares con estructura auto-ensamblada. Se describe la formación de complejos de co-encapsulación ordenados de cloruro y una molécula neutra en el interior de capsulas moleculares basadas en unidades de calixpirol. En un gran esfuerzo sintético, se preparó un contenedor molecular con topología de bis[2]catenano consistente en dos hemisferios de calixpirrol y calixareno unidos mecánicamente. La cavidad anisótropa permitió la co-encapsulación de N-oxidos pequeños con una molécula de disolvente. La gran estabilidad cinética de los complejos formados permitió la estabilización de un N-oxido inestable. La estabilidad termodinámica del complejo supramolecular se relacionó con la cinética de descomposición del N-oxido observado mediante modelos cinéticos. Finalmente, se estudia la síntesis y propiedades de contenedores moleculares con estructura covalente. La preparación de carcerandos formados por la unión (Hay coupling) de dos unidades de tetra-alquinil calixpirrol dio lugar a la formación inesperada de tetrámeros con estructura análoga a un nudo de ocho. El ensamblaje de capsulas covalentes dinámicas que contengan enlaces reversibles de tipo imina también se estudió usando un tetra-formil calixpirrol como esqueleto. En ambos casos se observó que el papel de una molécula plantilla que preorganice el sistema es fundamental para la síntesis eficiente de los contenedores.
This thesis comprises the synthesis and study of different molecular containers based on calix[4]pyrrole scaffolds. The molecular containers possess polar functionalized cavities ideal for the recognition of anions or N-oxides. The preparation of containers with enforced cavities (cavitands) results in the formation of highly stable (both thermodynamic and kinetically) complexes. The conformations adopted in solution by the host and the solid-state geometry are discussed in detail. Furthermore, we also explore the host-guest chemistry of self-assembled molecular containers. We describe the formation of ordered co-encapsulation complexes of chloride with neutral guests within self-assembled hydrogen-bonded molecular capsules having a calix[4]pyrrole core. In a great synthetic effort, a bis[2]catenane molecular container was prepared by the mechanical link of a calixpyrrole and a calixarene hemisphere. The anisotropic cavity of the bis[2]catenane allowed for the co-encapsulation of small N-oxides along with a solvent molecule. The high kinetic stability of the host-guest complexes allowed for the stabilization of a reactive propargylic N-oxide. The observed kinetic stability was related to the thermodynamics of the host-guest complex by a kinetic model. Finally, we studied the synthesis and properties of covalent molecular containers. The preparation of carcerand-like compounds by the Hay coupling of a tetra-alkynyl calix[4]pyrrole afforded the unexpected formation of a figure-of-eight-like structure. The assembly of dynamic covalent capsules bearing reversible imine bonds was also explored using a tetra-aldehyde calix[4]pyrrole as scaffold. In both cases, it was found that the role of the template was vital in the efficient synthesis of the containers.
16
Almaky, Mahdi M. Almahdi. "DNA-templated poly(N-substituted pyrrole)bipyridinium nanowires". Thesis, University of Newcastle upon Tyne, 2013. http://hdl.handle.net/10443/2127.
Testo completoAbstract (sommario):
Conductive polymers nanowires have been prepared using DNA-templating methods from monomer units designed in modular form. The monomer units comprise a polymerisable, pyrrolyl group, and a flexible alkyl linker attached to bipyridine groups in order to provide a metal-binding functionality within the polymers. The possibility for these DNA/polymer nanowires to act as templates for deposition of metal with enhanced electrical conductivity was also explored. Pyrrole with a flexible alkyl linker was combined with; pyridine (mono-I) as a control experiment, 2,2` bipyridyl (mono-II) and 4,4` bipyridyl (mono-III) with a metal ion binding site (nitrogen atom). This was in order to provide the metal-binding functionality for metal deposition to improve the conductivity as well as the morphology of the aimed hybrid templated nanowires. This series of pyrrole-pyridine derivatives were characterised using a range of techniques such as Proton Nuclear Magnetic Resonance (1H NMR) spectroscopy, Fourier Transform Infrared (FTIR) spectroscopy, Mass Spectroscopy (MS) and Elemental Analysis. Prior to the nanowires fabrication, pyrrole, as a control, and the prepared monomer units (mono-I, mono-II and mono-III) were chemically polymerised in a bulk scale using FeCl3 as an oxidant, then spectroscopic data and electrical conductivity of the resulting polymers were measured. A significant decrease in conductivity of poly-I, poly-II and poly-III compared to PPy, but was especially observed for the bipyridinium derivatives. This was suggested to be due to the steric hindrance of the alkyl side chain in the polymer backbone, in addition, the involvement of the non-quaternised pyridyl nitrogen in poly-II and poly-III by the nucleophilic attack on pyrrolyl groups in the polymerisation reaction. DNA-templated poly(N-substituted pyrrole)bipyridinium nanowires were synthesised at room temperature using the chemical oxidation method. The resulting CPs/DNA hybrids have been characterised using electronic and vibrational spectroscopic methods especially Ultraviolet-Visible (UV-Vis) spectroscopy and FTIR spectroscpy. The nanowires morphology was characterised using Atomic Force Microscopy (AFM). The electrical properties of the prepared nanowires were characterised using Electrostatic Force Microscopy (EFM), and measured using conductive AFM (c-AFM) and two iii terminal I/V technique, where the temperature dependence of the conductivity was probed. The conductivities of the prepared CPs/DNA nanowires are generally lower than PPy/DNA nanowires showing the large effect on N-alkylation in decreasing the conductivity of the polymer, but these are higher than the conductivity of their corresponding bulk films. This enhancement in conductivity could be attributed to the ordering of the polymer chains on DNA during the templating process. Finally, the prepared CPs/DNA nanowires were used as templates for the growth of copper nanowires at room temperature using aqueous solution of Cu(NO3)2 as a source of Cu2+ and ascorbic acid as reducing agent. AFM images showed that these nanowires were uniform and continuous compared to copper nanowires prepared using the templating method directly onto DNA. Electrical characterization of the nanowires by c-AFM revealed slight improvement in conductivity of these nanowires (Cu-CPs/DNA) compared to CPs/DNA nanowires before metallisation. Using similar preparation method, Poly-II/DNA nanostructures were also used as templates to direct the formation of Pd nanowires. An aqueous solution of PdCl2 was used as a source of Pd2+ ions and NaBH4 solution was used as reducing agent. AFM studies show that the resulting Pd-poly-II/DNA nanowires exhibit continuous and smooth morphology. Electrostatic Force Microscopy showed that these nanowires are electrically conductive.
17
Guyard, Laurent. "Etude et mecanismes de l'oxydation d'oligomeres de pyrrole". Besançon, 1997. http://www.theses.fr/1997BESA2037.
Testo completoAbstract (sommario):
Depuis plusieurs annees, les polyheterocycles ont ete beaucoup etudies car ils ont des proprietes conductrices dues a la grande delocalisation electronique a l'interieur de ces molecules. L'introduction d'un ou de plusieurs substituants sur ces molecules change considerablement les proprietes finales du polymere obtenu. Bien que de nombreux travaux aient ete realises dans ce domaine, la relation generale entre la nature du subsistuant, le potentiel redox du monomere et les proprietes finales du materiau obtenu sont encore insuffisamment connues. Pour ce qui est de la comprehension des proprietes des polymeres conducteurs, les oligomeres ont l'avantage d'etre des composes parfaitement definis, et les resultats obtenus a partir de leurs etudes peuvent souvent etre appliques aux polymeres parents. Par ailleurs, les oligomeres sont egalement des intermediaires dans les mecanismes d'electropolymerisation et leur etude est indispensable a la comprehension de ces processus. C'est dans ces deux grandes directions que se situe ce travail. Notre premier travail a donc consiste a mettre au point les syntheses d'oligomeres du pyrrole et du thiophene diversement substitues et de longueurs variables. Les principaux substituants etudies sont le methyle et le tert-butyle (que les positions et '), les substituants cyanophenyles (sur les positions ) ainsi que les substituants tert-butoxycarbonyle et phenylsulfonate (sur l'azote). Les composes synthetises ont ete caracterises du point de vue de leurs proprietes redox (e, temps de vie du radical-cation, k#s. . . ). Les differents comportements electrochimiques ont ete mis en evidence, en fonction de la nature du subsistant, ainsi qu'en fonction de la longueur du monomere de depart. Enfin, le comportement de trois composes specifiques (bipyrrole, 5-methyl-2,2'-bipyrrole, 5,5'-dimethyl-2,2'-bipyrrole), vis-a-vis d'une oxydation (chimique, electrochimique, par radiolyse pulsee ou photochimique) a ete analyse. Les resultats obtenus grace a differentes techniques analytiques (uv-visible, spectroelectrochimie, voltametrie cyclique) sont interpretes de facon a fournir des renseignements cinetiques et mecanistiques sur la formation du polymere.
18
VanNess, Brandon G. "Synthetic approach to epibatidine from 1-(phenylsulfonyl)pyrrole". Wright State University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=wright1183494979.
Testo completo
19
呂幹雄 e Kon-hung Lui. "Complementary approaches to 2,2-disubstituted 1,4-diketones, and the preparation and properties of 3H- and 3H-pyrroles derived from them". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1988. http://hub.hku.hk/bib/B31231299.
Testo completo
20
Kiani, Mohammad Saghir. "Structure and properties of pyrrole based electrically conducting polymers". Thesis, University of Reading, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316074.
Testo completo
21
Padroni, Giacomo. "Expanding the DNA binding repertoire of pyrrole-imidazole polyamids". Thesis, University of Strathclyde, 2018. http://digitool.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=29599.
Testo completoAbstract (sommario):
Pyrrole-Imidazole (Py-Im) hairpin polyamides are a programmable class of compounds that bind in the minor groove of double-stranded DNA (dsDNA). The hairpin conformationenables sufficient flexibility to form a side-by-side arrangement within the minor groove of target dsDNA sequences. An Im-Py pair discriminates G over C, A and T, whereas a Py-Pypair binds A and T over C and G. The possibility to target specific dsDNA sequences enables polyamides to modulate gene expression by the disruption of transcription factors such as the androgen receptor, over expressed in prostate cancer. A current limitation of the biological applications of Py-Im polyamides is their variable cell permeability profile. Im-richpolyamides tend to have reduced cellular and nuclear uptake in eukaryotic cells. Although modifications to the periphery of the polyamide scaffold have been explored at length, there has been limited studies on tuning the physicochemical properties of the G-recognising Imunit. This thesis describes the preparation and the evaluation of the binding mode of hairpin polyamides with Im units replaced by a series of 5-substituted 2-amino-4-carboxylic thiazole(Nt) building blocks. Chapter 1 introduces the endogenous and exogenous DNA recognition by protein and small molecules, the modulation of gene expression using Py-Im polyamides and the limitations of this approach. Chapter 2 describes the preparation of the building blocks and the optimisation of the solid phase synthesis of hairpin polyamides containing Nt units. These optimised conditions were used for the preparation of a suite of 8-ring polyamides incorporating Nt in different positions of the polyamide scaffold. Expanding the DNA binding repertoire of Pyrrole-Imidazole polyamides Chapter 3 describes the evaluation of the binding mode of Nt-containing polyamides using a combination of biophysical and biochemical methods. The 5-isopropyl substituted Nt (iPrNt) building block was identified as an alternative to Im for targeting G when incorporated at theN-terminus of the polyamide scaffold. Chapter 4 describes the structural characterisation of three selected polyamides binding to their dsDNA target sequence using NMR spectroscopy and molecular dynamics. This study reveals that the polyamide containing iPrNt at the N-terminus induces a greater compression of the major groove compared to the Im-containing analogue. Finally, Chapter 5 reflects on the work of this thesis and offers some perspective of the future development of Py-Im polyamides as gene expression modulators.
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Maaß, Christian. "Exploring Metal-Ligand Interactions of Pyrrole Based Pincer Ligands". Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2013. http://hdl.handle.net/11858/00-1735-0000-0022-5E31-1.
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Meure, Samuel James School of Chemical Engineering & Industrial Chemistry UNSW. "Development and characterisation of polypyrrole composites". Awarded by:University of New South Wales. School of Chemical Engineering and Industrial Chemistry, 2006. http://handle.unsw.edu.au/1959.4/24341.
Testo completoAbstract (sommario):
The development and characterisation of new PPy composites has been carried out using direct addition of polypyrrole (PPy) powders to polymeric substrates and in situ polymerisation in order to develop workable composites with conductivities similar to that of oxidised PPy. Precipitation, dispersion and emulsion polymerisation techniques were used in the development of PPy fillers. Electron microscopy, differential light scattering (DLS), nitrogen adsorption surface area analysis and conductivity measurements were used to determine the physical properties of PPy powders produced with ferric chloride oxidant. Powders possessing approximately 380-1400nm effective particle diameters, 8-50m2 surface areas and 0.001-1S/cm conductivities were produced. Physically mixed composites were produced by adding PPy powders to Surlyn ionomer, styrene ethylene butylene styrene triblock copolymers (SEBS) and nitrile butadiene rubber (NBR) hosts. Changes in physical properties (including tensile strength and electrical conductivity) of PPy and carbon black filled composites were also studied and compared. In situ polymerisation-based composite development of PPy composites with higher conductivities than obtained using physical mixing techniques (<10-4S/cm) was carried out. Sequential treatments with monomer and oxidant were used to test the combination of polymer host (including those described above) and reaction media (including tetrahydrofuran, diethyl ether and acetonitrile). Examination of PPy penetration and content (using optical microscopy and gravimetric analysis) showed a diethyl ether reaction media and SEBS host were suitable for further PPy Abstract composite development. The simultaneous diffusion polymerisation (SDP) technique, which involves treating opposite sides of host sheets with separate monomer and oxidant solutions, was employed to form PPy- SEBS composites. The layered morphology of SDP-formed composites was characterised by techniques including X-ray imaging, Raman mapping and electron probe microchemical analysis; and a PPy growth mechanism proposed. Optimisation of PPy composite properties was carried out using a central composite factorial design (varying reagent concentrations, reaction temperatures and reaction times) with conductivities of approximately 1S/cm achieved, Properties of PPy composites formed using physical mixing and SDP techniques were compared. Preliminary investigations (using electron and atomic force microscopy) were carried out to develop core-shell PPy composites that possess a continuous PPy component rather than the layered morphology associated with reductions in tensile strength.
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Jackson, Delwin S. "Synthesis and evaluation of peptidyl and non-peptidyl diphenyl phosphonate esters and a mechanistic study of hydroxy pyrrole and 4-nitroanlide substrates with serine proteases". Diss., Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/27142.
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Thamanavat, Kanrakot. "High Pressure Phase Equilibria in the Carbon Dioxide + Pyrrole System". Thesis, Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/4919.
Testo completoAbstract (sommario):
The objectives of this work are to measure phase equilibria in the carbon dioxide + pyrrole system and to correlate and predict the phase behavior of this system with a thermodynamic model. This binary system is of interest due to the growing applications of supercritical carbon dioxide as a solvent or reaction medium for pyrrole. Polypyrrole is an electrically conducting polymer of interest in a number of applications such as anti-static coatings. Pyrrole has also been used as a reactant in enzymatic reaction. Knowledge of the phase behavior of carbon dioxide + pyrrole system is therefore necessary for evaluating optimal conditions and feasibility of such applications.
Phase equilibria in the carbon dioxide + pyrrole system were measured at 313 K, 323 K, and 333 K using a synthetic method. Liquid-vapor (LV) phase behavior and liquid-liquid (LL) phase behavior were observed. The pressure in the experiments ranged from 84 to 151.1 bar. The Patel-Teja equation of state and the Mathias-Klotz-Prausnitz mixing rule with two temperature independent parameters was able to correlate the phase equilibrium data satisfactorily and was used to predict the phase behavior at other temperatures. A pressure-temperature diagram was then constructed from these calculations and suggests that the carbon dioxide + pyrrole system exhibit type IV phase behavior in the classification of Scott and van Konynenburg.
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Yazicioglu, Emre Yusuf. "Transformation Of Cyclohexanone Derivatives To Bicyclic Furan And Pyrrole Derivatives". Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605269/index.pdf.
Testo completoAbstract (sommario):
Tetrahydrobenzofurans and tetrahydroindoles are two very valuable classes of substances which have wide usage areaeither as starting materials for drug substances or many other compounds which have fused heterocyclic rings in their structures and pharmacophore for many complex natural products
syntheses of derivatives of these compounds with different substitution patterns, is an exciting challenge for many scientists. Benzofuran and tetrahydroindole derivatives, which are potent bioactive substances, are synthesized from various cyclohexanone derivatives that are allylated by Stork-enamine or Mn(OAc)3 mediated allylation methods. Allylated ketones are later transformed to benzofuran derivatives upon treatment with base or tetrahydroindole derivatives upon treatment with primary amines.
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KANT, ANKUR. "DESIGN AND PATTERNING OF POLY-PYRROLE INTERCONNECTS FOR COCHLEAR IMPLANT". University of Cincinnati / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1147376799.
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Devasurendra, Amila Manuradha. "Pyrrole-Based Conductive Polymer Composites for Electroanalysis and Chemical Separations". University of Toledo / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1513257195906402.
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Travert, Nathalie. "Métabolites pyrrole-2-aminoimidazoles marins bioactifs : réactivité et synthèse biomimétique". Paris 11, 2003. http://www.theses.fr/2003PA112120.
Testo completoAbstract (sommario):
Le travail qui est décrit dans ce mémoire est articulé autour de la réactivité des alcaloi͏̈des pyrrole-2-aminoimidazoles extraits d'éponges marines. Cette étude est notamment basée sur une hypothèse biogénétique qui permet d'expliquer la formation de la plupart de ces composés à partir de précurseurs simples tels que l'oroidine et le dispacamide A. Il existe au sein de cette famille des métabolites linéaires et polycycliques. L'acide 2-pyrrole carboxylique plus ou moins bromé et le 2-aminoimidazole constituent les éléments réactifs les plus importants dans cette série. Le manuscrit est composé de trois études indispensables à la synthèse biomimétique de cette famille d'alcaloi͏̈des: L'étude des réactions de cyclisation N1-C et C3-C intramoléculaires sur le pyrrole permet d'envisager une voie de synthèse vers de nombreux composés polycycliques. L'étude de l'oxydation et de l'ouverture de dimères pyrrole-proline ou proline-proline donne accès à des composés linéaires; elle nous a notamment permis la synthèse biomimétique du dispacamide A et de ses dérivés. L'analyse biomécanistique et la voie de synthèse de l'oroidine, de l'hyménidine et de la clathrodine en utilisant les N-acyl-1,2-dihydropyridines. L'ensemble de cette étude a permis de comprendre de nombreux mécanismes impliqués dans la réactivité des pyrrole-2-aminoimidazoles et de mettre en place une stratégie de synthèse biomimétique qui semble cohérenteThe work described in this manuscript is centered on the reactivity of pyrrole-2-aminoimidazole alcaloids isolated from marine sponges. This study is based on a biogenetic hypothesis which could explain the chemical pathways formation of most of this compounds, starting from very simple precursors like oroidine and dispacamide A. This family of compounds comprise linear and polycyclic structural groups. 2-Pyrrolecarboxylic acid, more or less brominated, and 2-aminoimidazole parts are the most important building blocks. The manuscript is divided into three studies: the study of N1-C and C3-C intramolecular cyclisations on pyrrole-aminoacids derivates allowed us to postulate a new synthetic scheme towards many polycyclic compounds belonging to this family. The study of dimeric pyrrole-proline or proline-proline systems and their biomimetic spontaneous transformations to dispacamide A and derivates. Biomechanistic analysis and the access to oroidine, hymenidine and clathrodine, using N-acyl-1,2-dihydropyridines. This general study allowed us to understand numbers of chemical mecanisms involved in the reactivity of pyrrole-2-aminoimidazole alcaloids
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Berlot, Isabelle. "Synthèse, caractérisation et étude électrochimique de tensioactifs dérivés du pyrrole". Université Joseph Fourier (Grenoble), 1998. http://www.theses.fr/1998GRE10087.
Testo completoAbstract (sommario):
Ce memoire est consacre a la synthese, la caracterisation et l'etude electrochimique de nouveaux tensioactifs derives du pyrrole, analogues du dodecyltrimethylammonium et associes aux contre-ions br#-, no#-#3, tso#-, bf#-#4. La plupart forment des micelles en solution aqueuse. Une electrode selective du cation dodecyltrimethylammonium a ete utilisee pour determiner leurs concentrations micellaires critiques (cmc). Nous avons aussi montre que la voltammetrie cyclique permet dans certains cas de determiner la cmc en milieu electrolytique, en depit du caractere irreversible de l'oxydation de la sonde redox que constitue le pyrrole. On constate que l'introduction d'un motif pyrrole a l'extremite de la chaine hydrocarbonee (series a1 et a2) ne modifie pas la cmc de ces tensioactifs par rapport a leurs analogues sans pyrrole. Par contre si le pyrrole est situe sur la tete polaire (serie b1), leur cmc est plus basse. L'etude par rmn#1h a eclaire ces constatations, en precisant la localisation des divers groupements dans la micelle : le pyrrole se place dans le cur hydrophobe dans le cas des a1 et a2, alors qu'il se replie vers l'interieur de la micelle pres de la tete polaire pour les b1. Dans le cas particulier des tensioactifs associes a l'anion tosylate, nous avons constate que le tosylate penetre dans la micelle et s'intercale entre les groupes ammonium. L'etude electroanalytique a montre que ces composes s'adsorbent fortement sur carbone et que des films de polypyrrole peuvent croitre sur ces electrodes par electrooxydation de solutions micellaires. Ces films sont electroinactifs, mais d'epaisseurs significatives (20 a 1000 couches monomoleculaires). Les rendements de depots sont faibles (5 a 10%) dans le cas des a1 et a2, mais nettement plus importants (50%) dans le cas des b1. L'electropolymerisation de solutions micellaires des series a1 et a2 conduit majoritairement a la formation d'oligomeres solubles, de type polypyrrole suroxyde.
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Cohen, Justin Delgado Grubbs Robert H. Dervan Peter B. "Programming protein patterns on DNA nanostructures with pyrrole-imidazole polyamides /". Diss., Pasadena, Calif. : Caltech, 2009. http://resolver.caltech.edu/CaltechETD:etd-11232008-171327.
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Bérubé, Christian Denis. "Delving into the rare-earth metal chemistry of pyrrole-based ligands: Synthesis and analysis of divalent samarium and ytterbium pyrrolide complexes". Thesis, University of Ottawa (Canada), 2001. http://hdl.handle.net/10393/9097.
Testo completoAbstract (sommario):
The reaction of YbI2(THF)2 with diphenylmethyldipyrrolide leads to a complex reaction from which is obtained an octameric divalent Yb macrocycle (Diphenyldipyrromethanedi-yl-Yb)8 2.1 as a major product, but from which is also isolated a tetrameric cyclic Yb(II)-oxo complex [(diphenyldipyrrolyl-methanedi-yl)Yb]4[(K2)(THF) 6](mu-O)•2(THF) 2.2•2(THF) and a monomeric Yb(III) complex, Yb(diphenyldipyrrolylmethane-di-yl)3(K 3THF3) 2.3, as minor products. Complex 2.1 is analogous to the Sm(II) dipyrrolide octameric clusters obtained under an argon atmosphere, which are thought to represent the intermediate species in the formation of dinitrogen complexes. The reactions of SmI2(THF)2 and YbI2(THF) 2 with the alkali salts of 2,5-dimethylpyrrole, or the reaction of SMCl 3(THF)3 and YbCl3(TBF)3 with the same ligands followed by reduction with the appropriate alkali metals, led to the formation of divalent mono- and polynuclear complexes. (Abstract shortened by UMI.)
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Garcia, Cruz Alvaro. "Micro et Nano structuration du Poly(pyrrole) sur substrat polymérique : développement d’immunocapteur pour la détection des biomarqueurs du cancer". Thesis, Lyon 1, 2015. http://www.theses.fr/2015LYO10105.
Testo completoAbstract (sommario):
Les techniques non-conventionnelles de lithographie ont fait depuis deux décennies une entrée remarquée dans les sciences de l'ingénierie. Elles sont considérées aujourd'hui comme un enjeu majeur pour le développement des dispositifs. L'objectif principal de cette thèse est d'explorer de nouvelles voies pour la conception des micro&nanabiocapteurs en procédant à des impressions de poly(pyrrole) (PPy) à haute résolution par microtamponnage assisté par polymérisation catalytique (nanoCP-CCP) sur des substrats polymériques (poly(téréphtalate) d'éthylène (PETE), Copolymère d'oléfine cyclique (COC), polyétheréthercétone (PEEK), poly(éthylène 2,6-naphtalate (PEN) et le polyamide (PI)). Dans un premier temps, nous avons mis au point différentes techniques d'impression (greffage par impression, impression adressée et impression directe) et des conditions de polymérisation pour moduler les caractéristiques de PPy micro et nano-structurés, afin de contrôler la taille, la forme et les propriétés électriques désirées. Nous avons constaté que les paramètres les plus importants qui influent sur le processus d'impression surtout à l'échelle nanométrique sont: a) Le rapport des concentrations des réactifs pour le procédé de polymérisation qui comprend le Py-silane, nitrate d'argent (AgNO3), le chlorure du fer (III)/ le chlorure de Lithium (FeCl3/LiCl). b) Les paramètres physiques de la machine GeSIM; la pression d'impression, le niveau de contact, le temps d'encrage du tampon polydiméthylesiloxane (PDMS), et le temps d'impression. Finalement, on est arrivé à fabriquer des nanofils de PPy (PPy-NF) de 747±12,2 nm de largeur, 114±8 nm de hauteur et avec une séparation de 573±13,4 nm entre deux PPy-NF consécutifs. Ces films micro et nano-structurés ont été caractérisées par microscopie électronique à balayage (SEM), microscopie à force atomique (AFM) et spectrométrie de photon-électrons induits par rayons X (XPS). Dans une deuxième partie, on a développé des immunocapteurs à base de PPy-NF sensible aux biomarqueurs interleukine 8 et 6. Pour cela, différentes stratégies ont été adoptées pour immobiliser les anticorps spécifiques à ces deux biomarqueurs. Ces immunocapteurs ont été caractérisés par la méthode de spectroscopie d'impédance électrochimique (EIS). Les résultats obtenus par rapport à la sensibilité et la sélectivité sont très satisfaisants avec des limites de détection de l'ordre de quelques pg/L pour les deux immunocapteurs développésNon-conventional lithography techniques have made for the two last decades a huge impact in the engineering sciences. They are now regarded as a main challenge for the development of the devices. The objective of this thesis is to explore new alternative possibilities for designing micro & nano biosensors based on poly(pyrrole) (PPy) high resolution microprinting attended by catalytic polymerization (nanoCP-CCP) on substrates Polymer (poly (terephthalate) ethylene (PETE), cyclic olefin copolymer (COC), polyetheretherketone (PEEK), poly (ethylene 2,6-naphthalate (PEN), and polyamide (PI)). In a first step We have developed various printing techniques (grafting printing, addressed printing and direct printing) and polymerization conditions to modulate the characteristics of PPy micro and nano-structured in order to control the size, shape and Electrical desired properties. We found that the most important parameters that affect the printing process especially at the nanoscale are: a.) The ratio of the concentrations of reagents for the polymerization process which includes the Py-silane, nitrate silver (AgNO3), iron chloride (III) / lithium chloride (FeCl3 / LiCl). b) The physical parameters of the GeSIM machine; the printing pressure, contact level, the inking time stamp of polydimethylsiloxane (PDMS), and printing time. Finally, we got to manufacture PPy nanowires (PPy-NW) 747 ± 12.2 nm wide, 114 ± 8 nm in height and with a separation of 573 ± 13.4 nm between two consecutive PPy-NW. These micro and nano-structured films were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM) and electron-photon spectroscopy induced by X-rays (XPS). In the second part, we have developed a PPy-NW-based immunosensors sensitive to interleukin 8 and 6 biomarkers. For this, different strategies have been adopted to immobilize antibodies specific to these two biomarkers. These immunosensors were characterized by electrochemical impedance spectroscopy method (EIS). The results obtained in relation to the sensitivity and selectivity are very satisfactory with the security detection limits of a few pg / L for both developed immunosensors
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Sazama, Graham Thomas. "Late First-Row Transition Metals in Weak Ligand Fields - Correlating High-Spin Electronic Structure and Reactivity". Thesis, Harvard University, 2013. http://dissertations.umi.com/gsas.harvard:11012.
Testo completoAbstract (sommario):
High spin has been shown to be necessary for optimal reactivity of transition metal complexes toward the activation and functionalization of C-H bonds. This thesis presents our examination of the weak-field, tripodal, trianionic tris(pyrrolyl)ethane (tpe) ligand and its complexes. Outer-sphere oxidation of the manganese, iron, cobalt, nickel and zinc complexes of tpe were performed by electrochemical and chemical methods. Electrochemical oxidation occurred at the same potential for each species, suggesting a ligand-based oxidation. The reaction product of chemical oxidation of iron showed oxidation of a pyrrole unit followed by H-atom abstraction to form a dichelated species. Density functional theory calculations confirm these results, and in silico oxidation of the complexes is entirely ligand-based. These results establish that tpe complexes are oxidized at the pyrrolide subunits in outersphere electron transfers, and elucidate minimal metal-ligand electronic communication. The more reactive \([(tpe)Fe(THF)]^−\) anion exhibits rapid binding of three equivalents of tert-butyl isonitrile, while reaction with excess carbon monoxide induces ligand fragmentation to form a species wherein two molecules of carbon monoxide have been reductively coupled. A mechanism based on the observed isonitrile species is proposed. The use of inner-sphere oxidant reagents allows for several stable iron (III) complexes of tpe to be isolated and characterized. Alkyl peroxides and alkyl disulfides, organic azides, and diphenyldiazomethane are all shown to oxidize iron by a single electron. Reaction with organic azides results in the formation of iron (III) amide species, likely as a result of Hatom abstraction. The weak-field of tpe creates a high propensity for forming high-spin iron (III) complexes, to the extent that diphenyldiazoalkane acts as a redox-active ligand and provides a one-electron reservoir to reveal a high-spin \(Fe^{3+}\). Spectroscopic and computational studies were undertaken to rigorously assign the physical oxidation state of iron in all cases. Given the outer-sphere redox liability of the tpe ligand, and the capability for inner-sphere oxidation local to iron, tpe complexes of iron represent a new class of metal-ligand redox activity, wherein the metal and ligand form two separate redox reservoirs, accessible via different mechanisms.Chemistry and Chemical Biology
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李思明 e Sze-ming Lee. "An investigation into novel synthetic routes for 3h-pyrroles". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1989. http://hub.hku.hk/bib/B31209257.
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Foloppe, Marie-Paule. "Synthèse et étude physico-chimique de N-(benzoyl) prolines et de pyrrolo (2,1-c) (1,4) benzodiazépines à visée thérapeutique". Caen, 1994. http://www.theses.fr/1994CAEN4057.
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Berini, Christophe. "Réaction des nitrones avec des pyrroles : accès à des N-hydroxylamines chirales. Applications à la synthèse d'acides alpha aminés". Université Joseph Fourier (Grenoble), 2008. http://www.theses.fr/2008GRE10102.
Testo completoAbstract (sommario):
Le noyau pyrrole est présent dans de nombreux produits naturels ainsi que dans des composés bio actifs. Le développement de méthodologies permettant la fonctionnalisation de cet hétéroaromatique s’avère donc un domaine de recherche particulièrement attractif. Dans ce contexte, nous avons mis au point une nouvelle méthode dans laquelle des pyrroles réagissent avec des nitrones en présence de chlorure d’hydrogène. Elle permet, selon les conditions expérimentales, d’accéder sélectivement et efficacement, soit à des N benzylhydroxylamines pyrroliques, soit à des 2,2’ bispyrrolylalcanes. Dans le but d’obtenir les N benzylhydroxylamines pyrroliques sous forme énantiopure, une version asymétrique de cette réaction a été développée à partir de nitrones chirales. Les produits sont isolés avec de bonnes diastéréosélectivités et de bons rendements. L’emploi d’une nitrone cyclique dérivée de glyoxylate a permis la synthèse de deux acides alpha aminés non naturels énantiomériquement enrichis en quatre étapes, la 2’ et la 3’ pyrrolylglycine, respectivement avec 22% et 50% de rendement global. Par ailleurs, cette méthodologie a été appliquée avec succès à la synthèse totale de l’Acide Penmacrique, un composé naturel isolé d’une légumineuse, Pentaclethra macrophylla, en 11 étapes avec un rendement global de 17%. L’évaluation des activités biologiques, en tant qu’anti‐angiogéniques et antibactériens, ainsi que l’activité sur le cytosquelette microtubulaire de plusieurs composés issus de ce travail sont présentéesThe chemistry of pyrrole and its derivatives is of great interest due to their abundance in many natural and biologically active compounds. The development of new methods to access to functionalized heterocyclic compounds is therefore a promising area. In this context, we have developed a method, in which pyrroles are added onto nitrones in the presence of hydrogen chloride. According to the experimental procedure, either pyrrolic N benzylhydroxylamines or 2,2’ bispyrrolylalkanes could be selectively and efficiently produced. In order to obtain chiral pyrrolic N benzylhydroxylamines, a stereoselective version of this reaction has been developed. Asymmetric inductions from chiral nitrones allow the access to pyrrolic N hydroxylamines with high levels of diastereoselectivities and good yields. The use of a glyoxylate based cyclic chiral nitrone leads to two enantio‐enriched non natural alpha amino acids, the 2’ and 3’ pyrrolylglycines in 22% and 50% overall yield respectively. Moreover, this method has been successfully applied to the total synthesis of Penmacric Acid, a natural product isolated from the seeds of Pentaclethra macrophylla, a leguminous tree, in 11 steps and 17% overall yield. Finally, the results of several biological assays have been performed. The properties as inhibitory of NorA efflux pump and anti‐angiogenic, as well as the activity on the microtubular cytoskeleton are presented
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Molina, Muriel Ricardo. "Calix[4]pyrrole based receptors for the recognition of ion pairs". Doctoral thesis, Universitat Rovira i Virgili, 2021. http://hdl.handle.net/10803/670970.
Testo completoAbstract (sommario):
La present tesis doctoral descriu la síntesis i estudis de reconeixement de receptors sintètics supramoleculars. Els
receptors estan basats en calix[4]pirrols capaços d’interaccionar amb espècies carregades així com amb espècies
neutres i polars a través de la formació d’enllaços d’hidrogen. Els estudis de reconeixement molecular s’han dut a
terme en dissolució a través de valoracions per RMN i per calorimetria (en anglès Isothermal Titration Calorimetry
ITC ) en cloroform. El complexes s’han caracteritzat també en fase gas utilitzant diferents tècniques d’espectrometria
de masses. En primer lloc, es presenta la síntesis d’una bis(calix[4]pirrole) basat en dos unitats de calix[4]pirrol unides
covalentment per dos anells de triazol com a espaiadors. El receptor sintètic reconeix sals de cianat i clorur de
tetraalquilamoni amb constants d’afinitat elevades. S’ha pogut demostrar que la geometria dels complexos i la
cooperativitat dels processos de reconeixement depenen del catió utilitzat. També s’ha estudiat la formació de
complexos amb topologia de pseudorotaxà assistida per parell iònics utilitzant un N-òxid com a component lineal. S’ha
observat la formació de dos isòmers diferents depenent de la coordinació del anió i del component lineal en cadascuna
de les dues cavitats no equivalents del receptor. Posteriorment, es descriu la síntesis d’un receptor amb topologia de
[2]rotaxà mitjançant la implantació de dos grups voluminosos als extrems del component lineal prèviament acoblat
amb el macrocicle (en anglès stoppering).La presente tesis describe la síntesis y los estudios de formación de complejos de receptor sintéticos supramoleculares. Los receptores están basados en calix[4]pirroles, capaces de interaccionar con especies cargadas así como con especies neutras y polares a través de la formación de enlaces de hidrogeno. Los estudios de formación de complejos se llevaron a cabo en cloroformo a través de experimentos de RMN y por calorimetría (en ingles Isothermal Titration Calorimetry, ITC) y en fase gas mediante el uso de técnicas basadas en ESI-MS. En primer lugar, presentamos la síntesis de un bis(calix[4]pirrol) basado en dos unidades de calix[4]pirrol unidos por dos anillos de triazol como espaciadores. El receptor sintético resultó ser adecuado para el reconocimiento de sales de tetraalquilamonio de cianato y cloruro con altos valores de constantes de afinidad. La geometría del complejo y la cooperatividad del evento eran dependientes del catión usado. También investigamos la formación de complejos pseudorotaxanados asistida por pares iónicos usando un N-óxido como componente lineal. Observamos la formación de dos isómeros diferentes dependiendo de la coordinación del anión y el componente lineal en cada uno de las dos cavidades del receptor. Posteriormente, describimos la síntesis de un receptor con topología de [2]rotaxano obtenido mediante la implantación de dos grupos voluminosos a los extremos del componente lineal previamente enhebrado en el macrocíclo (en inglés stoppering).
This thesis describes the synthesis and binding studies of supramolecular synthetic receptors. The receptors are based on calix[4]pyrrole architectures, able to interact with charged and neutral polar molecules by the establishment of hydrogen bonding interactions. The binding studies were performed in chloroform by means of NMR and ITC experiments and in the gas phase by ESI-MS techniques. We present the synthesis of a two-wall bis(calix[4]pyrrole) receptor based on two calix[4]pyrrole units linked by a triazole spacer. The synthetic receptor was able to bind tetraalkylammonium ion pairs of cyanate and chloride with high binding affinity, displaying different binding geometries and cooperativity depending on the bound cation. We then investigated the formation of [2]-pseudorotaxane complexes assisted by the same ion pairs, using a lineal N-oxide as the axle. We observed the formation of two different isomeric forms of the complexes obtained attending to the binding of the anion and the axle on each of the two different hemispheres of the receptor. We also report the synthesis of the [2]rotaxane receptor obtained by stoppering strategy and briefly discussed the binding properties towards ion-pairs. Finally, we describe the synthesis and binding studies of a strapped calix[4]pyrrole macrocycle decorated with a bis-amide unit as the strap.
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Maeda, Rina. "Synthesis and Evaluation of the Pyrrole-Imidazole Polyamides for Cancer Treatment". Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/263806.
Testo completoAbstract (sommario):
付記する学位プログラム名: 京都大学大学院思修館京都大学
新制・課程博士
博士(総合学術)
甲第23345号
総総博第18号
京都大学大学院総合生存学館総合生存学専攻
(主査)教授 山敷 庸亮, 教授 杉山 弘, 教授 積山 薫
学位規則第4条第1項該当
Doctor of Philosophy
Kyoto University
DGAM
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Sasaki, Shunta. "DNA sequence-specific alkylation by pyrrole-imidazole polyamides with indole linkers". 京都大学 (Kyoto University), 2008. http://hdl.handle.net/2433/136909.
Testo completo
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Shaw, Shannon Joanne. "The development of polypyrrole-based biosensors". Thesis, View thesis, 1994. http://handle.uws.edu.au:8081/1959.7/23336.
Testo completoAbstract (sommario):
The use of a conductive polypyrrole urea biosensor for the detection of urea in blood plasma is investigated.Urease was incorporated into a polypyrrole film by galvanostatic polymerisation. The presence of urea was verified, and the activity of the enzyme in the polypyrrole film was confirmed. The inherent electroactive properties of the polypyrrole-urease film has enabled the production of a flow injection amperometric biosensor for the reliable determination of urea. Greater sensitivity and stability was achieved when a pulsed amperometric detection system was implemented. The analysis of urea in human blood plasma by potentiometry, amperometry and pulsed amperometry was achieved with the assistance of an anion exchange separation prior to the electrochemical detection of urea. A polypyrrole-sulfite oxidase film was developed for use in an amperometric biosensor for sulfite determination. The response of the biosensor to sulfate was linear from 0 to 80 mg/L and the minimum detectable amount was 5 mg/L. Useful interferants in sulfite determination such as ascorbic acid, sodium nitrate and sodium sulfate did not respond to the biosensor. The excellent reproducibility of the sulfite response provides the basis for the construction of a disposable or renewable biosensor for sulfite determination. The analysis of sulfite in wine and beer was accomplished and no pretreatment was required.
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Cai, Xuediao. "Synthesis and Characterization of Pyrrole Based Adhesion Promoter Systems on Oxide Substrates". Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2005. http://nbn-resolving.de/urn:nbn:de:swb:14-1109334028224-37122.
Testo completoAbstract (sommario):
For grafting polypyrrole on oxidized surfaces, 3-substituted pyrrole alkyl phosphonic acids, 11-(pyrrol-3-yl undecyl) trimethoxysilanes and 1-substituted pyrrole alkyl organosilanes with different chain length were designed and successfully synthesized as adhesion promoters. These new derivatives were studied for their adsorption behavior on oxide substrates and chemical or electrochemical deposition of polypyrrole over modified oxide surface or electrodes. Several analytical techniques such as contact angle measurement, surface plasmon resonance spectroscopy (SPR), UV-VIS Spectroscopy, grazing incident FTIR, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and atomic force microscopy (AFM) were employed to characterize the adsorbed layers on different substrates. Contact angle measurement and ellipsometry data showed that high concentrations in apolar hydrocarbon solvent and long reaction times are sufficient to form tightly packed monolayer of 1-substituted pyrrole alkyl monochlorosilanes (PMCS) on substrates. Adsorption kinetics were studied by SPR and showed that the adsorption took place within a few seconds, then continuously increased and reached a plateau. The orientation of these synthesized monomers is investigated to be well-suited for use as adhesion promoter. CV-measurements showed that 3-substrated pyrrole derivatives had lower oxidation potential, whereas 1-substituted pyrrole derivatives had higher oxidation potential compared with pyrrole. Surface deposition of polypyrrole on the adhesion promoter modified (silane-modified and phosphonic acid-modified) substrates by chemical and electrochemical polymerization were investigated. PPy films formed on the modified surfaces by surface chemical polymerization showed a better adhesion compared to those on the unmodified surfaces. The morphology of PPy films was influenced by the alkyl chain length of the adhesion promoter and the deposition condition, such as choice of oxidant and solvent. The thickness of the resulting PPy films were controlled by the polymerization conditions, such as choice of solvent, deposition time, pyrrole to oxidant ratio and monomer concentration. The thickness of the deposited PPy film was estimated in the range of 10-400 nm by AFM and ellipsometry. The electrical properties were studied by current-voltage (j-V) measurement. Temperature dependence of j-V characteristics of Si/SiO2/PPy/PMCS-16/Al films revealed that the current increases with temperature, the film shows a typical semiconductor behavior. The use of these adhesion promoters modified electrode for electrochemical polymerization resulted in adhesive polypyrrole films.Also the 3-substituted pyrrole phosphonic acids were found to be homo-and co-polymerizable (with pyrrole) under chemical methods. TGA showed that homopolymers are less stable than polypyrrole due to the 3-substitution. he homopolymer of 3-substituted phosphonic acid derivatives of pyrrole is soluble. Films coated from the MeOH solution of homopolymer could be successfully used as humidity sensors. It is observed that the resistivity of the 3-substituted homopolypyrrole sensors increases and capacitance decreases during exposure to humid air. The polypyrrole films obtained by surface chemical polymerization was also used as humidity sensors.
43
Sandrin, Franco. "Lewis acid catalyzed reactions of 1-benzyl-2, 5-bis (trimethylsiloxy) pyrrole". Thesis, McGill University, 1985. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66047.
Testo completo
44
Duke, Andrew James. "An investigation of the properties of novel, poly(pyrrole)-based conducting polymers". Thesis, University of Southampton, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243095.
Testo completo
45
Evans, Louise Sarah. "Amido-pyrrole, isophthalamide andcalix[4]arene cleft-type receptors fpr anionic guests". Thesis, University of Southampton, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.444970.
Testo completo
46
Magness, Simon Lee. "Distributions and stable isotope characteristics of maleimides (1-H-pyrrole-2,5-diones)". Thesis, University of Bristol, 2001. http://hdl.handle.net/1983/c048b2c8-5524-4e7d-ac52-d473a31b78fb.
Testo completo
47
Cai, Xuediao. "Synthesis and Characterization of Pyrrole Based Adhesion Promoter Systems on Oxide Substrates". Doctoral thesis, Technische Universität Dresden, 2004. https://tud.qucosa.de/id/qucosa%3A24463.
Testo completoAbstract (sommario):
For grafting polypyrrole on oxidized surfaces, 3-substituted pyrrole alkyl phosphonic acids, 11-(pyrrol-3-yl undecyl) trimethoxysilanes and 1-substituted pyrrole alkyl organosilanes with different chain length were designed and successfully synthesized as adhesion promoters. These new derivatives were studied for their adsorption behavior on oxide substrates and chemical or electrochemical deposition of polypyrrole over modified oxide surface or electrodes. Several analytical techniques such as contact angle measurement, surface plasmon resonance spectroscopy (SPR), UV-VIS Spectroscopy, grazing incident FTIR, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and atomic force microscopy (AFM) were employed to characterize the adsorbed layers on different substrates. Contact angle measurement and ellipsometry data showed that high concentrations in apolar hydrocarbon solvent and long reaction times are sufficient to form tightly packed monolayer of 1-substituted pyrrole alkyl monochlorosilanes (PMCS) on substrates. Adsorption kinetics were studied by SPR and showed that the adsorption took place within a few seconds, then continuously increased and reached a plateau. The orientation of these synthesized monomers is investigated to be well-suited for use as adhesion promoter. CV-measurements showed that 3-substrated pyrrole derivatives had lower oxidation potential, whereas 1-substituted pyrrole derivatives had higher oxidation potential compared with pyrrole. Surface deposition of polypyrrole on the adhesion promoter modified (silane-modified and phosphonic acid-modified) substrates by chemical and electrochemical polymerization were investigated. PPy films formed on the modified surfaces by surface chemical polymerization showed a better adhesion compared to those on the unmodified surfaces. The morphology of PPy films was influenced by the alkyl chain length of the adhesion promoter and the deposition condition, such as choice of oxidant and solvent. The thickness of the resulting PPy films were controlled by the polymerization conditions, such as choice of solvent, deposition time, pyrrole to oxidant ratio and monomer concentration. The thickness of the deposited PPy film was estimated in the range of 10-400 nm by AFM and ellipsometry. The electrical properties were studied by current-voltage (j-V) measurement. Temperature dependence of j-V characteristics of Si/SiO2/PPy/PMCS-16/Al films revealed that the current increases with temperature, the film shows a typical semiconductor behavior. The use of these adhesion promoters modified electrode for electrochemical polymerization resulted in adhesive polypyrrole films.Also the 3-substituted pyrrole phosphonic acids were found to be homo-and co-polymerizable (with pyrrole) under chemical methods. TGA showed that homopolymers are less stable than polypyrrole due to the 3-substitution. he homopolymer of 3-substituted phosphonic acid derivatives of pyrrole is soluble. Films coated from the MeOH solution of homopolymer could be successfully used as humidity sensors. It is observed that the resistivity of the 3-substituted homopolypyrrole sensors increases and capacitance decreases during exposure to humid air. The polypyrrole films obtained by surface chemical polymerization was also used as humidity sensors.
48
DUCHENET, DEPIERRE VIRGINIE. "Monomeres et oligomeres fonctionnalises dans les series du thiophene et du pyrrole". Caen, 1996. http://www.theses.fr/1996CAEN2040.
Testo completoAbstract (sommario):
De nouveaux disulfures dissymetriques et cycliques ont ete prepares en serie thiophenique. Leur etude electrochimique a mis en evidence l'inhibition de polymerisation du cycle thiophenique par une telle fonction. Cependant, l'utilisation d'un terthiophene portant deux fonctions disulfures a permis d'abaisser le potentiel d'oxydation du monomere et de declencher une polymerisation, ouvrant une voie d'acces a ce type de polymeres fonctionnalises. Diverses tentatives de synthese de disulfures en serie pyrrolique ont ete entreprises sans succes. Une methode generale d'acces aux 4,4"-dialkylterthiophenes ainsi qu'aux n-alkyl-2,5-bis(4-alkylthien-2-yl pyrroles) jusqu'alors inconnus a ete decrite a partir de dicetones dibromees. L'approche proposee permet d'atteindre aisement des -quinqueheterocycles symetriquement bi et tetrasubstitues. Le comportement electrochimique de quelques uns de ces oligomeres a 3 et 5 membres contenant des unites thiopheniques et pyrroliques a ete etudie. Les effets sterique et electronique des substituants ainsi que le phenomene de couplage de deux radicaux cations lors de la reaction de dimerisation de quinqueheterocycles ont pu etre mis en evidence
49
Huang, Hao. "Quinone-Pyrrole Dyad Based Polymers for Organic Batteries : From Design to Application". Doctoral thesis, Uppsala universitet, Nanoteknologi och funktionella material, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-316492.
Testo completoAbstract (sommario):
Organic electrode materials are finding increasing use in energy storage devices due to their attractive properties that allow building of flexible and low weight devices in an environmentally friendlier manner than traditional alternatives. Among these organic electrode materials, conducting redox polymers (CRPs), consisting of conducing polymer (CP) with covalently attached redox active pendant groups (PG), have attracted our interests. This is due to the advantageous synergy between CP and PG, e.g. electronic conductivity, high stability and large charge storage capacity. In this thesis polypyrrole has been selected as CP and quinones as PGs. A series of quinone-pyrrole dyad polymers has been synthesized with a variety of quinone substituents, demonstrating the adjustability of quinone formal potentials by choice of substituents. Importantly, in this series we show that the CP-PG redox match, i.e. that the formal potential of the PG is within the conducting region of the CP, is a requirement for fast charge transfer from the electrode to the PGs. Moreover, a series of quinone-pyrrole dyad polymers with various linkers was synthesized, showing that the choice of linker has a pronounced impact on the interactions between the PG and CP. In addition, the temperature dependence of conductance during doping of the polymers reveals the charge transport mechanism. To summarize, the adjustability of the quinone formal potential as well as the fast charge transport in the bulk material ensures the applicability of the CRPs as electrode materials in organic batteries.
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Cortés, Sánchez Antonio Emilio. "A synthetic biology approach to the biosynthesis of novel pyrrole-amide antibiotics". Thesis, University of Strathclyde, 2016. http://digitool.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=28480.
Testo completoAbstract (sommario):
Novel antibiotics are desperately needed. We are on the verge of the pre-antibiotic era, with bacteria resistant to last resort drugs spreading quickly worldwide. Natural products, or chemical molecules produced by living organisms, evolved over time to interact with biological targets following rules that researchers have not yet outlined fully. However microorganisms, once the source of most of the drugs we use today, were abandoned in favor of synthetic chemistry, under the false premise that natural sources were depleted. When pursuing novel antimicrobials, two options are in hand, either drug discovery or drug functionalisation. In this thesis, approaches that were left on the golden era of antibiotic discovery due to technological limitations are revisited to produce derivatives of congocidine and distamycin. These two natural products are pyrrole-amide peptide antibiotics, characterised by antibiotic, antifungal, antiviral and antitumoral properties, which arise from their non-covalent DNA-binding properties. Since both antibiotics are chemically very close, this thesis explores the combinatorial biosynthetic opportunities to exploit between the pathways that encodes them. Their chemical outline enables them to bind rich AT sequences in the minor groove of the DNA, with different preferred motifs according to specific differences in peptide length and functional groups. Research on synthetic compounds imitating these two natural products, have shown that the DNA binding affinity can be modulated by peptide length and heterocycle content. As synthetic chemistry represents an inefficient approach for the production of these derivatised compounds based on the natural scaffold of concocidine, the in-vivo substitution of the pyrrole rings for other heterocycles such as imidazole or thiazole is pursued through a mutasynthetic approach. The last part of this study focuses on the resistance mechanism present in both clusters. Since both antibiotics are closely related, the study of their resistance mechanism can help understand how natural antimicrobial evolution shapes natural antibiotic resistance, and the structure to activity relationship of novel compounds are explored.