Spelling suggestions: "subject:"dipyrrole"" "subject:"1hpyrrole""
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Beiträge zur Kenntnis der Trimethinfarbstoffe aus PyrrolenWolf, Walther 04 April 1945 (has links)
No description available.
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Synthesis and Characterization of Pyrrole Based Adhesion Promoter Systems on Oxide SubstratesCai, Xuediao 09 February 2005 (has links)
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.
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Optické a elektrické vlastnosti nových materiálů pro organickou elektroniku a fotoniku / Optical and electrical properties of new materials for organic electronics and photonicsSionová, Marcela January 2012 (has links)
This diploma thesis is focused on the properties characterization of new organic materials with respect to their potential application in organic electro-optic devices. The theoretical part contains a themed literature search on application of organic materials for organic electronics and photonics. The basic principles of these devices are described. The practical part includes the preparation of thin films for organic photovoltaics of two types: based on low molecular weight organic compounds (diketo-pyrrolo-pyrroles derivates) and based on polymer (mixture of copolymer of poly(phenylenevinylene) and molecular senzitizer – derivate of fullerene). The first part of experiment is focused on characterization of optical and electrical properties of selected diketo-pyrrolo-pyrroles derivates and the second part is study the influence of annealing to polymer layer.
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SYNTHESIS OF FLUORINATED AND IODINATED CARBOXYETHYLPYRROLE RECEPTOR LIGANDSZhang, Yu 21 February 2014 (has links)
No description available.
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DNA Nanotechnology and Atomic Level Understanding for a Complex of DNA and a DNA Minor Groove Binder / DNAナノテクノロジーとDNAおよびDNAマイナーグルーブバインダーから成る複合体の原子レベルでの理解Abe, Katsuhiko 25 March 2024 (has links)
京都大学 / 新制・課程博士 / 博士(理学) / 甲第25128号 / 理博第5035号 / 京都大学大学院理学研究科化学専攻 / (主査)准教授 板東 俊和, 教授 深井 周也, 教授 秋山 芳展 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM
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The synthesis and evaluation of 1-methyl-3-pyrrolines and 1-methylpyrroles as substrates and inhibitors of monoamine oxidase B / Modupe O. OgunrombiOgunrombi, Modupe Olufunmilayo January 2007 (has links)
Very little is known about why and how the Parkinson's disease (PD) neurodegenerative process begins and progresses. In the course of developments for treatment of PD, the discovery of the inhibition of monoamine oxidase (MAO B) was a conceptual breakthrough, and has now been firmly established. MAO B has also been implicated in the neurodegenerative processes resulting from exposure to xenobiotic amines. For example, MAO B catalyzes the first step of the bioactivation of the parkinsonian inducing pro-neurotoxin, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Additional insight into the mechanism of catalysis of MAO B and the mechanism of neurotoxicity by MPTP is therefore very valuable in the pursuit of the treatment of PD. / Thesis (Ph.D. (Pharmaceutical Chemistry))--North-West University, Potchefstroom Campus, 2008.
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Synthesis And Electrochromic Properties Of Conducting Polymers Of 1-(4-nitrophenyl)-2,5-di(2-thienyl)-1h-pyrrole And Their Use In Electrochromic DevicesVaris, Serhat 01 January 2007 (has links) (PDF)
A new monomer / 1-(4-Nitrophenyl)-2,5-di-2-thienyl-1H-pyrrole SNSNO2 was synthesized through the Knorr-Paal condensation reaction of 1,4-di-2-thienyl-1,4-butanedione and p-nitroaniline. The chemical structure of monomer and polymer were characterized via Nuclear Magnetic Resonance Spectroscopy (NMR) and Fourier Transform Infrared Spectroscopy (FTIR). Chemical polymerization produced a polymer which was completely soluble in organic solvents. Electrochemical behaviors of SNSNO2 and SNSNO2 in the presence of EDOT were studied by cyclic voltammetry (CV). The synthesis of homopolymer and copolymer were achieved via constant potential electrolysis. Both homopolymer P(SNSNO2) and copolymer P(SNSNO2-co-EDOT) were characterized by various techniques including cyclic voltammetry, FTIR, Scanning Electron Microscopy (SEM) and UV-VIS Spectrophotometer. Conductivities of samples were measured by four probe technique. The electrochromic properties of the polymers were investigated via spectroelectrochemistry, colorimetry and switching studies. In addition, dual type electrochromic devices (ECDs) composed of P(SNSNO2), P(SNSNO2-co-EDOT) and poly(3,4-ethylenedioxythiophene) (PEDOT) were constructed and evaluated. Spectroelectrochemistry, switching ability and stability of the devices were investigated by UV-Vis Spectrophotometer and Cyclic Voltammetry. They have shown to possess good switching times, reasonable contrasts and high stabilities.
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Transition Metal-Mediated Syntheses of Yohimbane and Indolizidine Alkaloids / Übergangsmetall-vermittelte Synthesen von Yohimban- und IndolizidinalkaloidenAgarwal, Sameer 27 May 2005 (has links) (PDF)
Polycyclic nitrogen containing heterocycles form the basic skeleton of numerous alkaloids and physiologically active drugs. Alloyohimbane was obtained from 3,4-dihydro-â-carboline using an iron-mediated [2+2+1] cycloaddition as the key-step. The bis-TMS-diyne was conveniently obtained by the C-alkylation of 3,4-dihydro-â-carboline followed by N-alkylation. Demetalation of the iron-complex followed by hydrogenation, E-ring expansion, and reduction provided alloyohimbane, a structurally and biologically interesting substance, via a linear eight-step sequence in 7% overall yield based on 3,4-dihydro-â-carboline. Another sequence provided (±)-alloyohimbane and (±)-3-epi-alloyohimbane in nine steps. The pyrrole unit occurs in a variety of naturally occurring compounds, pharmaceutical products and polymers. A novel two-step procedure for the synthesis of pyrroles by addition of a propargyl Grignard reagent to a Schiff base and subsequent silver(I)-promoted oxidative cyclization of the resulting homopropargylamine has been developed. The generality of this reaction was proven by the synthesis of a broad variety of substituted pyrroles using silver(I)-promoted cyclization. A three-step synthesis of (±)-harmicine, a natural product isolated from the Malaysian plant Kopsia griffithii having strong anti-leishmania activity, from 3,4-dihydro-â-carboline is achieved by addition of 3-trimethylsilylpropargyl Grignard reagent, Ag(I)-promoted oxidative cyclization to a pyrrole, and chemoselective hydrogenation of pyrrole ring. Total synthesis of anti-tumor active crispine A and biologically active 1,2,3,5,6,10b-hexahydropyrrolo[2,1-a]isoquinoline have been achieved in three steps using silver(I)-promoted oxidative cyclization as key step.
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Etude de systèmes optiques pour l'analyse directe, en temps réel et en parallèle, d'interactions biomoléculairesGuédon, Philippe 11 May 2000 (has links) (PDF)
L'objet de ce travail de thèse a été de mettre au point un capteur biologique base sur l'utilisation de phénomènes optiques. Un capteur biologique se compose d'une couche réceptrice d'un transducteur et d'un système de lecture. Nous avons impose un cahier des charges relatif a ce capteur en termes de sensibilité par le biais du transducteur, de détection en parallèle de plusieurs interactions biologiques, et enfin, en termes d'optimisation de la couche réceptrice. L'étude de la sensibilité a consiste a comparer théoriquement et expérimentalement deux transducteurs optiques : la résonance des plasmons de surface (RPS) et le miroir résonant. Ce dernier possède une meilleure sensibilité que l'autre en théorie, mais la comparaison expérimentale nous a fait préférer la RPS. Puis, il a fallu adapter le détecteur à la détection en parallèle. Nous avons fait l'image de la couche réceptrice sur une camera CCD, nous permettant ainsi de suivre l'évolution de la totalité de la surface du capteur. Une première série d'expériences a été réalisée pour la reconnaissance entre des antigènes et des anticorps, ces derniers étant adsorbés passivement sur le capteur. Les résultats obtenus nous amenèrent à développer des procèdes biochimiques pour immobiliser les molécules sur la couche réceptrice. C'est ainsi que nous avons essaye différentes voies d'immobilisation pour les fragments d'ADN, pour ne retenir que le polypyrrole, optimisant la densité de surface des sondes d'ADN sur le capteur. De plus l'utilisation de ce polymère conducteur était tout a fait compatible avec l'adressage de plusieurs séquences d'ADN différentes sur le capteur. Le capteur biologique pouvait alors suivre toutes les interactions relatives aux séquences immobilisées. Nous avons alors applique le capteur a un problème clinique : la détection de mutations ponctuelles au sein d'un gène. Nous avons des lors montre que notre capteur était à même de discriminer la présence d'une base mutée sur toute une séquence.
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The synthesis and evaluation of 1-methyl-3-pyrrolines and 1-methylpyrroles as substrates and inhibitors of monoamine oxidase B / Modupe O. OgunrombiOgunrombi, Modupe Olufunmilayo January 2007 (has links)
Very little is known about why and how the Parkinson's disease (PD) neurodegenerative process begins and progresses. In the course of developments for treatment of PD, the discovery of the inhibition of monoamine oxidase (MAO B) was a conceptual breakthrough, and has now been firmly established. MAO B has also been implicated in the neurodegenerative processes resulting from exposure to xenobiotic amines. For example, MAO B catalyzes the first step of the bioactivation of the parkinsonian inducing pro-neurotoxin, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Additional insight into the mechanism of catalysis of MAO B and the mechanism of neurotoxicity by MPTP is therefore very valuable in the pursuit of the treatment of PD. / Thesis (Ph.D. (Pharmaceutical Chemistry))--North-West University, Potchefstroom Campus, 2008.
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