Dissertations / Theses on the topic 'Phenanthroline'
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Ott, Sascha M. "Acetylenic phenanthroline analogues, phenanthrolino-fused benzodehydrannulenes and their Ru(II)-complexes." Thesis, University College London (University of London), 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.271653.
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Boone, Lindsay Leighton. "The highly preorganized ligands 1,10-Phenanthroline-2,9-Dialdoxime and BIS-1, 10-Phenanthroline, and their complexing properties with metal ions /." Electronic version (PDF), 2006. http://dl.uncw.edu/etd/2006/boonel/lindsayboone.pdf.
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Rais, Daniela. "Supramolecular chemistry of metal anynyl and metal phenanthroline complexes." Thesis, Imperial College London, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.271988.
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Betancourt, Daniel. "Copper bis(phenanthroline) complexes as simple models for molecular transducers." Tallahassee, Fla. : Florida State University, 2008. http://purl.fcla.edu/fsu/lib/digcoll/undergraduate/honors-theses/368250.
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Thesis (Honors paper)--Florida State University, 2008.Advisor: Dr. Kenneth Goldsby, Florida State University, College of Arts and Sciences, Dept. of Chemistry and Biochemistry. Includes bibliographical references.
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Shemesh, Ely 1962. "TERNARY COMPLEXES OF COPPER(I), CYANIDE, AND 2,9-DIMETHYL-1,10-PHENANTHROLINE." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/291268.
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De, Kavita. "Applications of fluoro-alcohols as reaction media for the synthesis of heterocyclic compounds and perspectives in the design of hybrid materials." Paris 11, 2010. http://www.theses.fr/2010PA114821.
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Fluoro-alcohols like hexafluoroisopropanol (HFIP) and trifluoroethanol (TFE) display unique properties like high hydrogen bond donating ability, poor nucleophilicity, high ionizing power and low pKa’s compared to their non fluorinated counterparts. Owing to these properties HFIP/TFE are known to promote different reactions. HFIP was explored as an effective solvent system for the synthesis of 2,3-unsaturated glycosides via Ferrier rearrangement of 3,4,6 tri-O-acetyl glucal. Aza-Michael addition of anilines onto Michael acceptors was found to proceed easily in polar protic solvents like HFIP,TFE and water, without the assistance of any promoting agent. The reaction was found to depend largely on solvent as well as on the nature of the electrophile. The selectivity of the reaction to afford mono or diaddition products or even quinolines can be achieved by finely tuning the solvent. HFIP and TFE were explored as efficient solvent systems for the Povarov reaction in the synthesis of nitrogen containing heterocycles. The applications of the Povarov/ oxidation reaction were studied further in the synthesis of the hetereocycles like aminoquinolines and phenanthrolines. We also assessed the synthesized phenanthrolines as potential ligands in two different reactions like AuCl-catalyzed C-C double bond cleavage and the oxidative Heck coupling. On the other hand, keeping into consideration the growing demand of green chemistry, we synthesized a recoverable novel hybrid organic-inorganic material containing HFIP moiety. The novel material was used as an organo-catalyst in the reactions: sulfoxidation, epoxide opening with aromatic amines, aza-Michael, Ferrier rearrangement. Unfortunately the preliminary studies were not encouraging. On the other hand, due to the presence of HFIP moiety, the material might bind selectively with specific functional groups and thus might find applications in drug delivery as a good drug carrier as well. In a preliminary study the novel material has shown considerable adsorption towards carboxylic acidsLes alcools fluorés comme l’hexafluoroisopropanol (HFIP) et trifluoroéthanol (TFE) possède des propriètes uniques (aptitude à former des liasons hydrogène, une faible nucléophilie, un fort pouvoir ionisant et un faible pKa) qui sont très differents de celles de leur analogues hydrogénés. Grace à leur propriètes, les alcools fluorés peuvent promouvoir des réactions differentes. Nous avons montré que HFIP est un solvant efficace pour réaliser la réaction de Ferrier. Le 3,4,6-Tri-O-acétyl glucal a réagi avec alcools différents pour donner des glucosides 2,3-insaturés. Ainsi nous avons étudié la réaction d’addition d’amines aromatiques sur les accepteurs de Michael dans les solvants polaires protiques. Nous avons ainsi démontré que la réaction d’aza-Michael des amines aromatiques pouvait être promue et contrôlée par simple effet de ces solvants. Selon la nature du solvant et de l'électrophile, la sélectivité de la réaction peut être affinée pour mener des produits de mono-ou di-addition ou même quinoléines selon une cascade d’addition/cyclialkylation/déshydratation. Nous avons montré que HFIP et TFE sont des solvants très efficaces pour la synthèse de la 8-aminoquinoléines par une séquence Povarov/oxydation, à partir des réactifs simples (1,2-phénylènediamines, aldéhydes et éthers vinyliques). Une deuxième séquence Povarov/oxydation donne des phénanthrolines substitués à position C-2 ou C-9. Les phénanthrolines synthétisés ont été étudiés en tant que ligands dans deux réactions différents: i) clivage oxydatif de C=C (double liaison carbone-carbone) catalysée par AuCl; ii) le couplage oxydatif de Heck catalysée par Pd(OAc)2. Vu la demande croissante de la chimie verte, nous avons synthétisé de nouveaux matériaux décorés avec des fractions HFIP pour servir comme catalyseurs récupérables. Malheureusement, les études préliminaires ne sont pas encourageantes et aucun effet catalytique significatif n’a été observé dans les réactions de sulfoxydation, d'ouverture d’époxyde par des amines aromatiques, la réaction d’aza-Michael avec des amines aromatiques et la réaction de Ferrier. D'autre part, nous avons envisagé que, en raison de la présence du groupement HFIP, le matériau hybride organique-inorganique pourrait former des liaisons hydrogène avec certains groupements fonctionnels présents dans des principes actifs, et pourraient donc trouver des applications en tant que transporteur de médicaments. Dans une étude préliminaire, le nouveau matériau a montré une adsorption importante d'acides carboxyliques
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Eggers, Friederike [Verfasser]. "2,9-Diaryl-1,10-phenanthroline für molekulare Erkennung, Metallo- und Organokatalyse / Friederike Eggers." Kiel : Universitätsbibliothek Kiel, 2008. http://d-nb.info/101955343X/34.
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Reck, Lisa Maria [Verfasser]. "Enantiomerenreine konkave 1,10-Phenanthroline - Liganden für die enantioselektive Metallkatalyse / Lisa Maria Reck." Kiel : Universitätsbibliothek Kiel, 2014. http://d-nb.info/1053653549/34.
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Gaeva, Elena B. "Thermal equilibrium, photochromism and acidicromism of some spirooxazines of phenanthroline and naphtalene." Toulouse 3, 2006. http://www.theses.fr/2006TOU30086.
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Les mérocyanines proviennent de la rupture de la liaison spiro des spirooxazines photochromiques. Bien que les mérocyanines soient généralement instables, des conditions appropriées permettent de les stabiliser. Deux séries de phenanthrolinospirooxazines et de spironaphthoxazines portant un groupement O-alkyl en position 5 ont été étudiées. Selon leurs structures, différentes techniques permettent d'ouvrir la forme spiro et de stabiliser la mérocyanine. Pour les phenanthrolinospirooxazines spirooxazines, la proportion de mérocyanine augmente avec la polarité du solvant. Pour les spironaphthoxazines, une protonation colore la solution en rouge. Un photochromisme négatif a été observé. Une modélisation numérique des données enregistrées dans les deux séries permet de déterminer plusieurs paramètres photochromiques. Ces propriétés présentent de grandes potentialités pour de futures applications (capteurs spécifiques, éléments logiques).Merocyanines derive from the spiro bond cleavage of photochromic spirooxazines. Although merocyanines are generally unstable, appropriate conditions can stabilize them. Two series of spirophenanthrolinoxazines and spironaphthoxazines bearing the O-Alk chain in position 5 have been studied. According to their structures, different techniques allow to open the spiroform and to stabilize the merocyanine. For spirooxazines of phenanthroline series, the merocyanine content raises significantly with the solvent polarity. For spironaphthoxazines, protonation turns the solution red and negative photochromism has been observed under visible light irradiation. Numerical modelling has been applied to analyse the recorded data within the two series. Several interesting photochromic parameters have been determined. The investigated properties have great potential applications for future specific sensors or logic elements
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Huesgen, Brian. "Structure and synthesis of four supramolecular structures involving Cu(I) and 4,7-phenanthroline." Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/4965.
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Thesis (M.S.)--University of Missouri-Columbia, 2007.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed Oct. 26, 2007). Vita. Includes bibliographical references.
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Edwards, Alyn. "The development of 1,10-phenanthroline-derived extractants for advanced future nuclear fuel cycles." Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/the-development-of-110phenanthroline-derived-extractants-for-advanced-future-nuclear-fuel-cycles(50b1ff9e-9cc5-4252-9769-0a949858a80c).html.
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The design, synthesis and evaluation of 1,10-phenanthroline derived extractants for the separation of the trivalent minor actinides (An(III)) from the chemically analogous trivalent lanthanides (Ln(III)) is described herein. In addition to providing an exclusive mechanistic insight into the extraction behavior of 2,9-bis-triazinyl-1,10-phenanthroline (BTPhen) ligands, this research encompasses substantial synthetic progress and identifies a number of new and improved candidates for An(III) partitioning in advanced future nuclear fuel cycles.
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Bose, Rakesh. "Amperometric detection of aldosterone by high-performance liquid chromatography with copper(II) bis-phenanthroline /." Connect to online version, 1995. http://hdl.handle.net/1989/3553.
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Wang, Siwen. "Development of Novel Phenanthroline and Thiazole Orange Derived G-quadruplex Ligands and Telomerase Inhibitors." Scholarly Commons, 2018. https://scholarlycommons.pacific.edu/uop_etds/3167.
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The end of the human chromosome is protected by telomeres which contain a special tandem guanine-rich DNA sequence, 5’-TTAGGG. The length of telomeres is shortened during cell replications, and its length limits the replication capacity of cells. Telomerase is over-expressed in 85–90% of cancer cells, responsible for extending the telomere length in cancer cells. Guanine-rich DNA sequence can self-assemble into unique G-quadruplex structures that interfere with the extension of telomeres by telomerase. Therefore, DNA G-quadruplex has recently received much attention because of its important regulatory functions in telomerase-mediated cancerization. The formation of G-quadruplex requires monovalent cations (Na+ and K+) or small molecules known as G-quadruplex ligands. In the present work, we developed a serial of G-quadruplex ligands by tethering side-chains to two core structures: 1,10-phenanthroline (Phen) and thiazole orange (TO). Biophysical studies including DNA thermal denaturation monitored by fluorescence orcircular dichroism, fluorometric titration, and ESI-MS spectrometry reveal that the binding of the synthesized ligands to G-quadruplex is side-chain dependent. The arylsulfanyl side chains significantly improve the binding affinity and selectivity of 1,10-phenanthroline towards G-quadruplex over duplex DNA. The polyamine side chains are a suitable structural motif for remarkable G-quadruplex binding affinity based on the results from both Phen and TO derivatives. These ligands greatly inhibit the telomerase activity in vitro, determined by a modified telomeric repeat amplification protocol (TRAP) assay. Amongst these promising telomerase inhibitors, a thiazole orange derivative containing a side chain of spermine shows an outstanding telomerase inhibition effect at nanomolar concentrations, which is comparable to the most effective synthetic telomerase inhibitors, BRACO-19.
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Dean, Nolan Edward. "Metal ion complexing properties of the highly preorganized ligand 1, 10-phenanthroline-2,9-dicarboxylic acid /." Electronic version (PDF), 2007. http://dl.uncw.edu/etd/2007-3/deann/nolandean.pdf.
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Stührenberg, Kai [Verfasser]. "Phenanthroline-based copper complexes for water splitting applications : photo-physical and spectroscopic investigations / Kai Stührenberg." Paderborn : Universitätsbibliothek, 2017. http://d-nb.info/1149721782/34.
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Djomgoue, Paul. "N3, N4/(N3S, N3O) and N6 Phenanthroline Bases and their Spin Crossover Iron(II) Complexes." Doctoral thesis, Universitätsbibliothek Chemnitz, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-207498.
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The present dissertation focuses on the synthesis of iron(II) complexes and the study of their SCO behavior. The equilibrium between the HS and the LS states gives to the SCO systems large potential applications for molecular electronics. However, today there is not a single molecular device from SCO compounds in the market. This is due to the fact that the SCO systems discovered up to now were unable (e.g. TLIESST « 300 K) for these applications. The aim of this thesis is to synthesize new SCO compounds with sustainable properties for applications. In the beginning of the thesis, [Fe(rac-22a))]2+∙2[BF4]- and [Fe(rac-22b)]2+∙2[BF4]- employing rigid hexadentate ligands were described. In contrast to the expectation, the N-methylation of the amines shifts the equilibrium towards the LS state. [Fe(rac-22b)2+∙2[BF4]- shows a T1/2 higher at 74 K and 52 K than the non methylated [Fe(rac-22a)2+∙2[BF4]- respectively in nitrobenzene and acetonitrile. The T1/2 are solvent-dependent for these complexes. After that, ligand series 9-R2-2-(6-R1-pyridin-2-yl)-1,10-phenanthroline 25b (R2 = Me), 25f (R2 = Ph), 25d (R2 = C(O)H), 25c (R1 = Ph), 25l (R1 = oxylphenyl-4-oxymethylene), 25m (R1 = oxymesitylene) and 25j (R1 = pyrol-1-yl) were synthesized. It was observed that the size of the substituent influences the SCO properties (T1/2). In addition, the influence of the counterion was shown with [Fe(25c)2]2+∙2[BF4]- and [Fe(25c)2]2+∙2[B(Ph)4]-. The B(Ph)4- conterions bring π∙∙∙π interactions in the molecular cell which shift the T1/2 parameter to a high temperature (200 K) compared to the complex with BF4- ions (175 K). Moreover the substituents R1 on the terminal position of the pyridine effect on T1/2 more than the substituents R2 on the terminal position of the phenanthroline. For example, [Fe(25f)]2+∙2[BF4]- (R1 = Ph) is a pure HS complex while the complex [Fe(25c)]2+∙2[BF4]- (R2 = Ph) is a SCO system (T1/2 = 175 K). The expansion of the coordination mode from N6 to N8 was investigated by the synthesis of the tetradentate ligands. This expansion shows an unexpected coordination mode, [Fe(25i)2]2+∙2[BF4]- (R2 = pyrazol-1-yl) forms a distorted square antiprism coordination geometry (HS iron(II)-complex) and does not show any Fe-N bond breaking over the application of the temperature as expectedDie vorliegende Dissertation behandelt die Synthese von Eisen(II)-Komplexen und ihr spin crossover (SCO)-Verhalten. Das Gleichgewicht zwischen high-spin (HS)- und low-spin (LS)-Zustand verleiht den SCO-Systemen eine großes Anwendungspotential im Bereich der molekularen Elektronik. Dennoch existiert bis heute kein SCO-basiertes molekulares Bauteil auf dem Markt. Hauptgrund hierfür ist, dass die bislang bekannten SCO-Systeme keine hinreichenden Eigenschaften (z.B. TLIESST « 300 K) aufweisen. Das Ziel der vorliegenden Arbeit ist die Synthese neuer SCO-Verbindungen mit geeigneten Eigenschaften für die Anwendung. Zu Beginn der Arbeit werden die Komplexe [Fe(rac-22a)]2+∙2[BF4]– und [Fe(rac-22b)]2+ ∙2[BF4]– mit starren hexadentaten Liganden beschrieben. Entgegen der Erwartung verschiebt die N-Methylierung der Amine das Gleichgewicht in Richtung des LS-Zustandes. Verglichen mit dem nicht-methylierten Komplex Fe(rac-22b)]2+∙2[BF4]– zeigt Fe(rac-22a)]2+∙2[BF4]– eine höhere Übergangstemperatur T1/2, welche in Nitrobenzen 74 K und in Acetonitril 52 K beträgt. Für die Komplexe ist T1/2 lösungsmittelabhängig. Im Folgenden wurde die Ligandenserie 9-R2-2-(6-R1-pyridin-2-yl)-1,10-phenanthrolin mit den Vertretern 25b (R2= Me), 25f (R2 = Ph), 25d (R2 = C(O)H, 25c (R1 = Ph), 25l (R1 = oxyphenyl-4-oxymethylen), 25m (R1 = oxymesitylen) und 25j (R1 = pyrol-1-yl) hergestellt. Es wurde beobachtet, dass die Größe des Substituenten das SCO-Verhalten (T1/2) beeinflusst. Ergänzend wurde der Einfluss des Gegenions anhand der Komplexe [Fe(25c)]2+∙2[BF4]– und [Fe(25c)]2+∙2[B(Ph)4]– untersucht. Das Gegenion B(Ph)4– ermöglicht intra- und intermolekulare π···π-Wechselwirkungen in der Zelle, welche die Übergangstemperature T1/2 (200 K) gegenüber dem BF4–-Komplex (175 K) erhöhen. Des Weiteren beeinflussen die Substituenten R1 an der Pyridin-Einheit die ubergangskomplexes T1/2 stärker als die Substituenten R2 an der Phenanthrolin-Einheit. So ist [Fe(25f)]2+∙2[BF4]– (R1 = Ph) ein reiner HS-Komplex, während der Komplex [Fe(25c)]2+∙2[BF4]– (R2 = Ph) ein SCO-System ist (T1/2 = 175 K). Die Erhöhung der Koordinationszahl von N6 auf N8 wurde über die Synthese von tetradentaten Liganden untersucht. Diese Erhöhung führt zu einem unerwarteten Koordinationsmodus. So bildet [Fe(25i)]2+∙2[BF4]– (R2 = pyrazol-1-yl) eine quadratisch-antiprismatische Koordinationssphäre (HS Eisen(II)-Komplex) und zeigt, wie erwartet, über den untersuchten Temperaturbereich keine Fe–N-Bindungsspaltung
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FRANCOIS, JEAN CHRISTOPHE. "Nucleases artificielles specifiques de sequences d'adn et arn : oligodesoxyribonucleotides couples a la 1, 10-phenanthroline." Paris 6, 1989. http://www.theses.fr/1989PA066189.
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Le complexe cuivrique de la 1,10-phenanthroline (op) induit en presence d'un agent reducteur et d'oxygene, la coupure de la chaine phosphodiester d'un acide nucleique. Le couplage de cette (op) sur un oligodesoxyribonucleotide a permis d'obtenir des molecules capables de reconnaitre specifiquement une sequence nucleique complementaire de l'oligonucleotide et de degrader specifiquement la cible choisie grace a l'activation chimique de l'(op). Diverses sequences cibles adn et arn en simple brin ont ete utilisees. Une triple helice peut-etre formee entre un oligopyrimidine et une sequence d'adn homopurine-homopyrimidine. Par des techniques d'empreinte, nous avons montre que l'oligonucleotide se fixait dans le grand sillon de l'adn. Un oligopyrimidine dirige contre la sequence de reconnaissance d'une endonuclease de restriction est capable d'inhiber specifiquement l'activite enzymatique de celle-ci grace a la formation d'une triple helise. Nous presentons aussi des resultats obtenus avec des oligopyrimidines couples a l'(op) diriges contre des sequences d'adn lineaire en double brin. Ces oligonucleotides-(op), une fois fixes sur leur substrat complementaire et apres activation chimique, induisent avec une grande efficacite une coupure double brin de leur adn cible. Ces oligonucleotides couples a l'(op) diriges contre des cibles simple brin ou double brin pourront etre utilises dans un avenir proche comme outils de biologie moleculaire (endonucleases artificielles) ou encore comme modulateurs de l'expression genetique in vitro et in vivo agissant sur la traduction ou la transcription d'un gene
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FROIDEVAUX, JEROME. "Etudes physico-chimiques d'une porphyrine de zinc a chapeau phenanthroline : reconnaissance selective de bases azotees." Université Louis Pasteur (Strasbourg) (1971-2008), 1998. http://www.theses.fr/1998STR13202.
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Ce travail s'inscrit dans le cadre d'une approche physico-chimique des relations structure-reactivite de porphyrines superstructurees a l'interface entre les domaines de la reconnaissance moleculaire et de la chimie bioinorganique. Ce manuscrit presente la caracterisation d'un ligand ditopique rigide, constitue d'une anse diphenyle-phenanthroline et d'un macrocycle porphyrinique, ainsi que l'analyse detaillee des proprietes complexantes de la metalloporphyrine de zinc correspondante envers des substrats azotes. Ce travail contribue a demontrer que les interactions entre une metalloporphyrine et des substrats (ligands) axiaux sont controlees par l'environnement immediat du macrocycle tetrapyrrolique. En effet, la complexation de bases azotees analysee par electrochimie, spectroscopie uv-visible et rmn du proton montre que la reconnaissance selective de ces substrats est rendue plus efficace par l'adequation entre la taille de la cavite du recepteur et la taille du substrat, et par la complementarite d'interactions forte (liaison de coordination zinc-azote) et faibles (liaisons hydrogene, empilements aromatiques) autour de la metalloporphyrine de zinc mono-anse. Cette combinaison d'interactions permet d'obtenir pour la premiere fois des complexes stables d'insertion et de choisir selectivement la face de complexation correspondante au site proximal et distal de la porphyrine. Pour illustrer cette possibilite, la synthese d'un complexe heterodinucleaire zn(ii)/cu(i) ou chaque centre metallique est independant, a ete realisee. A partir des informations obtenues lors de la reconnaissance de bases azotees par la metalloporphyrine de zinc, l'insertion d'un substrat imidazolate entre les deux centres metalliques dans la cavite du complexe a ete realisee et le complexe d'insertion zn(ii)-imidazolate-cu(i) a ete caracterise. Les structures radiocristallographiques des differents complexes obtenus montrent que le ligand suppose rigide est capable de se deformer soit pour optimiser le developpement d'interactions entre le substrat et le recepteur, soit pour complexer le cation cuivreux a la phenanthroline du recepteur. En vue d'appliquer ces concepts a la realisation d'un modele de cytochrome c oxydes, la porphyrine de fer correspondante a egalement ete prepare et etudiee.
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Whitchurch, Christian J. "Development of a Novel Electrochemiluminescent Reaction Involving Cadmium." Ohio University / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1011035988.
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Gephart, Raymond Thomas. "The highly preorganized ligand 2,9-BIS(Hydroxymethyl)-1,10-Phenanthroline, and its complexation properties with metal ions /." Electronic version (PDF), 2006. http://dl.uncw.edu/etd/2006/gephartr/raymondgephart.pdf.
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GERMANO, GLEICE CONCEICAO MENDONCA. "STUDY OF INTERACTIONS OF THE ANTIBIOTIC NORFLOXACIN AND ITS COPPER-PHENANTHROLINE COMPLEX WITH DRUG DELIVERY SYSTEMS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2018. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=36049@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE EXCELENCIA ACADEMICA
Os sistemas de administração controlada de medicamentos (drug delivery) permitem a introdução de uma substância terapêutica no organismo e melhoram sua eficácia e segurança, controlando a taxa, o tempo e o local de liberação, o que diminui os efeitos colaterais.Nesse trabalho nos dedicamos a estudar dois possíveis sistemas de administração de fármacos: lipossomos associados a surfactantes, já bastante utilizados em farmacologia, e nanobastões de ouro, cujas propriedades únicas têm sido avaliadas em aplicações biomédicas. Os lipossomos têm-se destacado devido a sua estabilidade e baixa toxicidade, os surfactantes são tensoativos muito usados tanto em farmacologia como para estabilizar soluções coloidais de nanopartículas. Já os nanobastões de ouro têm perspectivas promissoras para utilização em entrega de fármacos devido a suas propriedades óticas e biocompatibilidade. Estudamos, por meio de espectrofotometria de fluorescência e de absorção UV-visível, a associação entre esses sistemas e uma classe de fármacos denominada fluorquinolonas, que são antibióticos de amplo espectro bacteriano. A norfloxacina (NFX), pertencente à segunda geração de fluorquinolonas, foi escolhida para esse trabalho por ser naturalmente fluorescente, o que facilita a análise das interações sem a introdução de sondas extrínsecas ao sistema. Segundo a literatura, a associação da NFX com íons metálicos produz modificações nas propriedades desse fármaco, como solubilidade e biodisponibilidade. Essas mudanças têm sido avaliadas como uma possível solução ao problema de resistência bacteriana a antibióticos. Esse trabalho foi dividido em duas partes: na primeira, estudamos a formação dos complexos ternários de NFX com cobre-fenantrolina em presença de lipossomos associados a surfactantes que modificam a distribuição de carga elétrica superficial desses sistemas; na segunda parte estudamos a associação de NFX a nanobastões de ouro estabilizados por diferentes surfactantes.
Drug delivery systems allow the introduction of a therapeutic substance into the body and improve its effectiveness and safety by controlling the rate, time and place of release, which reduces side effects. In this work, we study two possible drug delivery systems: liposomes associated with surfactants, which are already widely used in pharmacology, and gold nanorods, whose unique properties have been evaluated in biomedical applications. Liposomes have been remarkable because of their stability and low toxicity, and surfactants are widely used both in pharmacology and to stabilize colloidal solutions of nanoparticles. On the other hand, gold nanorods have promising perspectives for use in drug delivery due to their optical properties and biocompatibility.We study the association between these systems and a class of drugs called fluoroquinolones, which are broadspectrum bacterial antibiotics, using fluorescence spectrophotometry and UVvisible absorption. Norfloxacin (NFX), a second generation fluoroquinolone, was chosen because it is naturally fluorescent, which facilitates the analysis of interactions without the introduction of extrinsic probes into the system. According to the literature, the association of NFX with metal ions produces changes in the properties of this drug, such as solubility and bioavailability. These changes have been evaluated as a possible solution to the problem of bacterial resistance to antibiotics. This work was divided in two parts: first, we studied the formation of the ternary complexes of NFX with copper-phenanthroline in the presence of liposomes associated to surfactants that modify the distribution of surface electric charge of the systems; in the second part, we studied the association of NFX to gold nanorods stabilized by different surfactants.
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Hounsou, Sedjro Candide. "Conception, synthèse et études biologiques de nouveaux inhibiteurs de la telomerase." Paris 6, 2004. http://www.theses.fr/2004PA066159.
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Huang, Wei. "Structure, electronic, and photophysical properties of platinum(ii) biphenyl complexes containing 2,2’-bipyridine and 1,10-phenanthroline derivatives." Diss., Wichita State University, 2010. http://hdl.handle.net/10057/3649.
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Platinum(II) biphenyl diimine complexes have been synthesized and characterized.
Single crystal X-ray structures from seven complexes show two types of configurations about the
platinum coordination sphere in the solid state: X and B (butterfly). The two configurations give
different circular dichroism spectra (CD) based on their C2 or Cs symmetry. The metal-to-ligand
charge transfer (MLCT) bands which occur at ~440 nm are transitions from d orbitals on the
platinum metal center to * orbitals of the diimine ligands. This agrees with the time dependant
density functional theory (TDDFT) calculations where the lowest unoccupied molecular orbitals
(LUMO) are located on diimine ligands.
Emission spectra of the complexes can be divided into three groups according to different
emission excited states: group I, ligand centered transitions (LC); group II, ligand field
transitions (LF) and group III, metal-to-ligand charge transfer (MLCT). Emission profiles from
the groups are different from one another: LC transitions have vibronic structures; LF transitions
have sharp peaks without vibronic structure and MLCT transitions have a broad peak without
vibronic structure. Linear free energy correlations were found between emission maxims,
reduction potentials and emission lifetimes with Hammett sp values. The diimine with electron
donating substituents have the higher energy emission maxima and the longer emission life time.
The diimine with electron withdrawing substituents has the lower energy emission maxima and
the shorter emission life time.Thesis (Ph.D.)--Wichita State University, College of Liberal Arts and Sciences, Dept. of Chemistry
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Melton, Darren Landon. "Metal ion complexing properties of the two-dimensional, highly preorganized ligand 1, 10-Phenanthroline-2, 9-Dicarboxylic acid /." Electronic version (PDF), 2005. http://dl.uncw.edu/etd/2005/meltond/darrenmelton.pdf.
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Salez, Hervé. "Synthèse de dérivés d'acridine et de benzo-(b)-1,7-phenanthroline : étude de leurs propriétés chimiques, physicochimiques et pharmacologiques." Université Joseph Fourier (Grenoble ; 1971-2015), 1991. http://www.theses.fr/1991GRE10171.
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Terry, Tracy J. "Immobilized bis-phenanthroline coordination sites in porous silica : characterzation and reactivity of manganese(II) and iron(II) complexes /." May be available electronically:, 2007. http://proquest.umi.com/login?COPT=REJTPTU1MTUmSU5UPTAmVkVSPTI=&clientId=12498.
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Listorti, Andrea <1981>. "Copper(I) phenanthroline complexes and supramolecular systems containing fullerenes: Photophysics, photochemistry and potential applications in sustainable energy technologies." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1463/1/Listorti_Andrea_tesi.pdf.
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Chemistry can contribute, in many different ways to solve the challenges we are facing to modify our inefficient and fossil-fuel based energy system. The present work was motivated by the search for efficient photoactive materials to be employed in the context of the energy problem: materials to be utilized in energy efficient devices and in the production of renewable electricity and fuels.
We presented a new class of copper complexes, that could find application in lighting techhnologies, by serving as luminescent materials in LEC, OLED, WOLED devices. These technologies may provide substantial energy savings in the lighting sector. Moreover, recently, copper complexes have been used as light harvesting compounds in dye sensitized photoelectrochemical solar cells, which offer a viable alternative to silicon-based photovoltaic technologies. We presented also a few supramolecular systems containing fullerene, e.g. dendrimers, dyads and triads.The most complex among these arrays, which contain porphyrin moieties, are presented in the final chapter. They undergo photoinduced energy- and electron transfer processes also with long-lived charge separated states, i.e. the fundamental processes to power artificial photosynthetic systems.
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Listorti, Andrea <1981>. "Copper(I) phenanthroline complexes and supramolecular systems containing fullerenes: Photophysics, photochemistry and potential applications in sustainable energy technologies." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1463/.
Full textAbstract:
Chemistry can contribute, in many different ways to solve the challenges we are facing to modify our inefficient and fossil-fuel based energy system. The present work was motivated by the search for efficient photoactive materials to be employed in the context of the energy problem: materials to be utilized in energy efficient devices and in the production of renewable electricity and fuels.
We presented a new class of copper complexes, that could find application in lighting techhnologies, by serving as luminescent materials in LEC, OLED, WOLED devices. These technologies may provide substantial energy savings in the lighting sector. Moreover, recently, copper complexes have been used as light harvesting compounds in dye sensitized photoelectrochemical solar cells, which offer a viable alternative to silicon-based photovoltaic technologies. We presented also a few supramolecular systems containing fullerene, e.g. dendrimers, dyads and triads.The most complex among these arrays, which contain porphyrin moieties, are presented in the final chapter. They undergo photoinduced energy- and electron transfer processes also with long-lived charge separated states, i.e. the fundamental processes to power artificial photosynthetic systems.
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Cockrell, Gregory Mercer. "The highly preorganized ligand 2, 9-DI-(2'-PYRIDYL)-1, 10-Phenanthroline, and its complexation properties with metal ions /." Electronic version (PDF), 2007. http://dl.uncw.edu/etd/2007-1/cockrellg/gregorycockrell.pdf.
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Fouilland, Laura. "Synthesis of novel 1.10-phenanthrolins and cyclic analogs, a potential anticancer and antimalarial agents." Thesis, KTH, Skolan för kemivetenskap (CHE), 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-32945.
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The potential antimalarial and anticancer effect of molecules containing 1,10-phenanthroline skeleton has been suspected on several previous studies. It is why the goal of this project is to synthesize novel 1,10-phenanthrolines and cyclic analogs. The originality of this project is the synthesis way of these novel compounds. Indeed, these structures will be obtained through an original redox approach developed in the SMITH laboratory using the tetrakis(dimethylamino)ethylene (TDAE) reagent. The TDAE is an electron rich organic molecule which is an effective reducing agent capable of generating an anion from halogenated derivatives under mild conditions via a single electron transfer (SET). From the different substrate we will work with, the TDAE will generate an anion which will be additioned on the 1,10-phenanthroline-5,6-dione. These different substrates will be aromatic and heterocyclic nitro-benzylic, and quinonic derivates as well as bromodifluoromethyl heteroarylated substrates. A one pot two step (reduction, dehydration) reaction will be done on these addition products, in order to obtain a cyclised product. It is the first time we try these reactions on these kind on molecules, it is why this project needs a lot of optimization and that the yield obtained are medium or equal to zero. However, we observed that the addition reaction with TDAE worked with 4 substrates out of 6. We tried the cyclisation reaction on only one addition product and we think that after some improvement of the reaction conditions and the work-up, we will be able to obtain the product with a good yield.Tidigare studier har indikerat att molekyler med 1,10-phenanthrolineskelett har en skyddande effekt mot malaria och cancer. Syftet med detta projekt är att syntetisera nya 1,10-phenanthrolinar och cykliska analoger. Framställningsmetoden som användes i denna studie har inte undersökts tidigare. Föreningen skapades genom en originalmetod utnyttjande en redoxreaktion med hjälp av en TDAE-reagens. TDAE är en elektronrik organisk molekyl och fungerar som en effektiv reduktionsagent. Med hjälp av en enelektronöverföring (SET) kan en anjon framställas under milda förhållanden utifrån halogena derivat. Anjonen tillförs 1,10-phenanthroline-5,6-dione. De olika substraten är heteroaromatiska nitro-benzyliska och quinoniska derivat, samt bromodifluorometylheteroarylerade. Cykliska produkter erhölls genom en tvåstegsreaktion (reduktion, dehydratisering) genomförd i ett enda reaktionskärl. Med detta projekt har dessa reaktioner för första gången testats på den här typen av molekyler. Det krävs mer optimering eftersom utbytena var låga till medelhöga. Utav sex möjliga substrat fungerade additionsreaktionen med TDAE med fyra stycken. I detta försök testades dock endast en cyklisk reaktion på additionsprodukten. Med ytterligare förbättringar av reaktionsvillkor och upparbetningar förväntas man kunna producera önskad produkt i gott utbyte.
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Girardot, Camille. "Synthèses et propriétés en optique linéaire et non linéaire du troisième ordre de complexes de coordination à ligans 5-oligofluorène-phénanthroline." Lyon, École normale supérieure (sciences), 2005. http://www.theses.fr/2005ENSL0345.
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Boudot, Clotilde. "Recherche de nouvelles molécules trypanocides." Thesis, Limoges, 2019. http://www.theses.fr/2019LIMO0078.
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Les maladies à kinétoplastidés sont des parasitoses vectorielles dues à des protozoaires flagellés sanguicoles. Parmi celles-ci, la Trypanosomose Africaine due à un parasite du genre Trypanosoma touche à la fois les Hommes et les animaux. Chez l’Homme, cette maladie, plus connue sous le nom de maladie du sommeil, évolue classiquement en 2 stades. Le stade hémolymphatique où le parasite se multiplie dans le sang et la lymphe et le stade nerveux caractérisé par la présence du parasite au niveau cérébral. En l’absence d’une thérapeutique adapté, la mort est inéluctable. Actuellement les traitements proposés en médecine humaine comme vétérinaire sont anciens, non dénués de toxicité et sont à l’origine de cas de résistances de plus en plus marqués. La recherche de nouvelles molécules est donc primordiale pour pouvoir espérer maitriser cette pathologie. C’est dans ce contexte que nous avons étudié deux familles de molécules capables de reconnaitre des sites parasitaires : (i)Les nitroimidazolés qui vont interagir avec les nitroréductases pour générer des intermédiaires toxiques, et (ii) les dérivés phénanthroliniques ciblant les télomérases afin de perturber la synthèse d’ADN du trypanosome. Notre travail de thèse a permis d’évaluer le pouvoir trypanocide de différentes molécules de ces deux familles à la fois par des tests in vitro mais aussi sur un modèle murin infecté par une souche de Trypanosoma brucei brucei. La finalité de ce travail étant d’identifier de nouveaux candidats médicaments. Les résultats obtenus ont permis de mettre en évidence des composés d’intérêt qui ouvrent de nouvelles voies de recherche pour lutter contre cette parasitose, mais aussi plus largement contre tous les kinétoplastidésKinetoplastid diseases are vectorial parasitoses caused by flagellated blood protozoa. Among these, African Trypanosomiasis, due to a parasite of the genus Trypanosoma, affects both humans and animals. In humans, this disease, known as sleeping sickness, progresses classically in 2 stages: the hemolymphatic stage characterized by multiplication of the parasite in blood and lymph and the nervous stage characterized by the presence of the parasite in the brain. In the absence of appropriate therapy, death is inevitable. Currently, the treatments proposed in human and veterinary medicine are old, toxic and at the origin of cases of resistance. The search for new molecules is therefore essential to control this pathology. It is in this context that we studied two families of molecules which recognize parasitic sites: (i) Nitroimidazoles that interact with nitroreductases to generate toxic intermediates, and (ii) Phenanthroline derivatives targeting telomerases to disrupt trypanosome DNA synthesis. Our thesis research evaluated the trypanocidal power of different molecules from these two families both by in vitro tests and in a mouse model infected with a strain of Trypanosoma brucei brucei. The purpose of this work was to identify new drug candidates. The results obtained have made it possible to identify compounds of interest that open up new pathways of research to control this parasite, as well as all kinetoplastidae
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Phetxumphou, Katherine. "Consumers and Their Drinking Water: Communicating Water Quality and Assessing the Reaction of Zerovalent Nanoiron (nZVI) with Saliva." Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/49260.
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Human senses for taste, odor, and visual assessment allow consumers to be selective when it comes to choosing their drinking water. In addition to wanting aesthetically pleasing water to drink, consumers want to know if their water is safe and may have misconceptions on what possible health risk contaminants could be lurking in their water supply. This thesis aimed to measure reaction of zerovalent nanoiron (nZVI) in water and human saliva, evaluate consumer's perceptions of taste, odor, and risk in their drinking water, and investigate the effectiveness of community water systems in communicating water quality information to their consumers.
Since nZVI, including commercially available Nanofer 25S, is widely being used in water treatment processes and has future potential for use in fortifying foods, the exposure to these engineered nanoparticles will increase for humans and aquatic organisms. Thus, the first part of the thesis was to develop a quantitative analytical technique to measure the iron levels at environmentally relevant concentrations. Researchers developed a colorimetric assay using 1, 10-phenanthroline as an assay to determine the amount of ferrous ions produced from different iron materials, including ferrous(II)sulfate, nZVI, and goethite. Resulting ferrous ion measurements indicate that the maximum production of ferrous ions varied among the iron materials. Nanofer25S did not undergo 100% conversion to ferrous ions, as expected, goethite had no production of ferrous ions, and ferrous(II)sulfate was 100% ferrous ions. The total iron, as measured by atomic absorption for all iron materials were equal. The reactivity of these iron materials were also assessed in different water qualities ranging in salt concentrations. The capacity to produce ferrous ion did not change when added to nanopure water, tap water, and inorganic solution that is equivalent to the high ionic strength of saliva.
Toxicology data for nZVI exposure to humans and aquatic organisms are limited. For that reason, authors of this manuscript measured salivary lipid oxidation (SLO) potential for the different iron materials in human saliva. They also developed an artificial saliva recipe to ensure repeatability and comparable results among laboratories due to human saliva's variability day by day. This simulated human saliva contained salts, proteins, and lipids. Using thiobarbituric acid reactive substances (TBARs), both Nanofer25S and ferrous(II)sulfate induced in-vitro SLO with human saliva. Goethite was unreactive. SLO results from this study have implications for flavor effects of nZVI in drinking water.
The second chapter of this thesis is assessing the clarity of message communication of Consumer Confidence Reports (CCRs). In 1998, the United States Environmental Protection Agency (USEPA) mandated that community water systems (CWSs) provide annual water quality reports to their consumers. These CCRs summarize information regarding water sources, any detected contaminants, compliance with federal regulations, and educational information. Thirty CCRs across all ten USEPA regions were analyzed for clarity using the Centers for Disease Control and Prevention's (CDC) Clear Communication Index (CCI) tool. The analysis of these CCRs was a national representation of CWSs and revealed that currently distributed CCRs performed poorly on the CDC's CCI—all failing to meet the 90% passing mark. The overall average score for all CCRs was 50.3 ± 13.5%. The clarity scores were based on seven key areas: 1) Main message and call to action; 2) Language; 3) Information design; 4) State of the science; 5) Behavioral recommendations; 6) Numbers; and 7) Risk. Improvements in all seven areas—with the lowest average scores at 3.3 ± 18.1%, 21.7 ± 26.6%, and 37.7 ± 27.1%, respectively, for state of science, language, and main message and call to action—of the CCI will greatly improve the quality and educational capabilities of CCRs. The failing scores highlight the challenges facing CWSs in communicating water quality information. This assessment can serve as a tool for water utilities to effectively prepare and distribute information to their consumers in the future. CWSs must promote a two-way dialogue with their consumers. They should address consumer's concerns and wants in the CCRs, and they should also effectively communicate risks to the consumers so that they are not under the misconception that their water is unsafe to drink. CWSs should use the CCRs as a way to educate the public and promote drinking tap water.
The last chapter of this thesis addresses the concerns that consumers may have about their drinking water and methods that could be implemented to quickly and efficiently respond to consumer complaints and contaminants with sensory properties. Just like CWSs, consumers are concerned about their water; they are the sentinels to water quality monitoring because they are uniquely positioned at the tap. Consumers are able to detect the slightest taste, odor, and appearance in their drinking water because it is well—instinctive! Thus, consumer feedback and complaint data provided to a utility should be taken seriously and stored for future comparisons. Any consumer complaint represents a fruitful data stream that should be harnessed routinely to gain knowledge about aesthetic water quality in the distribution system. Four utilities provided consumer complaints on water quality data that were categorized and visualized using radar and run-time plots. As a result, major taste, odor, and appearance patterns emerged that clarified the issue and could provide guidance to the utilities on the nature and extent of the problem.
Consumer complaint data is valuable for water quality issue identification, but CWSs should understand that even though humans readily identify visual issues with water, such as color, cloudiness, or rust, describing specific tastes and particularly odors in drinking water is acknowledged to be a much more difficult task for humans to achieve without training. This was demonstrated with two utility groups, laboratory personnel and plant operators, and a group of consumers identifying the odor of orange, 2-MIB, and DMTS. All of the groups were able to identify the familiar orange odor. However, the two utility groups were much more able to identify the musty odor of 2-MIB; this may be due to the fact that the utility groups are more familiar with raw and finished water. DMTS, a garlic-onion odor associated with sulfur compounds in drinking water, was the least familiar to all three groups. The lab personnel group was the better describers of the odor, but the results within this group still varied significantly. These results suggest that utility personnel should be mindful of consumers who complain that their water is different, but cannot describe the problem. To reduce the inability to describe an odor or taste issue, a TandO program at a utility can be beneficial.
The safety and aesthetic characteristics of drinking water is most important to consumers. They both complement each other; if consumers think their water tastes funny, they would probably assume that is unsafe to drink. Since nZVI is increasingly being introduced into the drinking water supply, researchers must be able to understand how it reacts in humans and the environment. Additionally, CCRs would be an effective method for CWSs to communicate water quality information and address any concerns consumers may have about their water. CWSs can use implement the radar and run-time plots to identify issues in the drinking water systems. Also, TandO programs will allow CWSs and their consumers to better describe and identify the issues in their drinking water as it arises so that it can be easily addressed and alleviated. Thus, promoting communication between water utilities and their consumers will improve the relationship and instill confidence in consumers about their drinking water.Master of Science
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Gaver, Charles Richard. "The highly preorganized ligands 8-(2-Pyridyl) Quinoline, 2,2'-dipyridyl amine and 1,10-phenanthroline-2, 9-dicarboxylic acid, and their complexing properties with metal ions." View electronic thesis, 2008. http://dl.uncw.edu/etd/2008-3/gaverc/charlesgaver.pdf.
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Djomgoue, Paul [Verfasser], Heinrich [Akademischer Betreuer] Lang, Heinrich [Gutachter] Lang, and Birgit [Gutachter] Weber. "N3, N4/(N3S, N3O) and N6 Phenanthroline Bases and their Spin Crossover Iron(II) Complexes / Paul Djomgoue ; Gutachter: Heinrich Lang, Birgit Weber ; Betreuer: Heinrich Lang." Chemnitz : Universitätsbibliothek Chemnitz, 2016. http://d-nb.info/1214377289/34.
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Vidal, Pierre-Louis. "Synthèse et caractérisation de ligands polymères conjugués alternant oligothiophènes et complexes de métaux de transition de type bis(1,10-phénanthroline)." Université Joseph Fourier (Grenoble), 1999. http://www.theses.fr/1999GRE10142.
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Ce travail a consiste a elaborer differents ligands polymeres conjugues alternant oligothiophenes et complexes cuivre-bis(1,10-phenanthroline). La demarche utilisee a ete la suivante : la synthese de ligands precurseurs conjugues constitues d'une 1,10-phenanthroline disubstituee en positions 2,9 ou 3,8 par des troncons polymerisables bi- ou ter-thiophenes (ligands t2, t3, f2me) a ete realisee. Le pouvoir assembleur de cu(i) a ete utilise pour encastrer deux de ces ligands identiques autour de lui. L'electropolymerisation des complexes ainsi formes a conduit a un premier type d'architectures, constituees de chaines de polymere conjugue entrelacees autour du cuivre, alternant 1,10 phenanthroline et oligothiophene (polycu(tn) 2, n = 2,3). L'enfilage d'un de ces ligands au travers du macrocycle coordinant m30 via ce meme pouvoir assembleur du cu(i) a permis apres electropolymerisation l'obtention d'architectures polyrotaxates conjugues parfaitement definies (polycut2m30, polycu(f2me)m30). Les proprietes redox de ces materiaux et leur aptitude a complexer reversiblement differents metaux de transition ont ete etudiees par voltamperometrie cyclique. En particulier, la reversibilite de la complexation de cu(i) dans le cas des polyrotaxates est parfaite uniquement lorsque le cation lithium est present lors de son enlevement, jouant un role de support intermediaire labile. La reprise d'autres metaux de transition apres enlevement de cu(i) est possible dans le cas de polycu(f2me)m30. L'environnement du cuivre au sein des polymeres a ete evalue par des mesures de spectroscopie d'absorption x (couplees ou non a l'electrochimie) : dans tous les cas, l'environnement proche du cuivre est constitue de quatre azotes et se trouve nettement plus contraint que celui de composes modeles monomeres. Enfin, des mesures de resistance couplees a la voltamperometrie cyclique ont permis la mise en evidence d'une contribution du cuivre a la conductivite du polymere polycu(t3) 2.
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FernaÌndez, Iglesias Eva. "Liquid-crystalline phenanthrolines." Thesis, University of Exeter, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.269721.
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Ferretti, F. "HOMOGENEOUS CATALYTIC REDUCTIVE CARBONYLATION OF ORGANIC NITRO COMPOUNDS: BIDENTATE NITROGEN LIGANDS AS A KEY POINT." Doctoral thesis, Università degli Studi di Milano, 2013. http://hdl.handle.net/2434/214936.
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The reductive carbonylation of nitro compounds is a process with a high potential synthetic and industrial interest, since many products can be obtained from nitro compounds and CO, including isocyanates, carbamates, ureas and heterocyclic compounds. The most active systems in this kind of reactions are based on the use of a transition metal catalyst and a nitrogen ligand. In this PhD thesis studies on reduction by carbon monoxide of palladium complexes relevant to the reaction of carbonylation of nitroarenes are reported. Moreover catalytic studies were conducted on the use of differently substituted nitrogen ligands in the palladium catalyzed synthesis of methyl N-phenylcarbamate. In particular the effect of non symmetric ligands on the activity of the catalytic system and the use of long alkyl chain substituted phenanthrolines for catalyst recycling are discussed. A system based on a palladium/phenanthroline complex was also investigated for the reductive cyclization of beta-nitrostyrenes to indoles: the optimization of the reaction and its scope are reported.
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Patel, Mohit Pratish. "OPTIMIZATION AND APPLICATION OF PHOTOLUMINESCENCE- FOLLOWING ELECTRON-TRANSFER WITH TRIS(TETRAMETHYL- 1,10-PHENANTHROLINE) Os/Ru(III) COMPLEXES AND FENTON BASED CHEMILUMINESCENCE DETECTION OF NSAIDS AND DOPAMINE IN BIOLOGICAL SAMPLES." Diss., Temple University Libraries, 2016. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/385393.
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ChemistryPh.D.
Biogenic monoamines such as dopamine play an important role as major neurotransmitters. Simultaneous determination of the concentration changes is thus crucial to understand brain function. Additionally, quantification of pharmaceutically active compounds (PhACs) and their metabolites in biological fluids is an important issue for forensic tests, clinical toxicology and pharmaceutical analysis. We have developed two postcolumn luminescence detection methods coupled to a 2-dimensional-solid phase extraction (2D-SPE) system. The postcolumn reaction methods used in this study are the redox-dependent photoluminescence-following electron-transfer (PFET) and Fenton-based chemiluminescence techniques, for the determination of certain neurotransmitter and nonsteroidal anti-inflammatory drugs (NSAIDs). A stable [Os(tmphen)3]3+ (tmphen = 3,4,7,8-tetramethyl-1,10-phenanthroline) reagent was prepared in neutral aqueous solution by oxidation of [Os(tmphen)3]2+ with lead(IV) oxide. [Os(tmphen)3]2+ and [Os(tmphen)3]3+ are characterized by absorption spectroscopy. [Os(tmphen)3]3+ stability is compared with [Ru(tmphen)3]3+ in the same pH 7 environment. The properties of Os(III) and Ru(III) complexes were investigated for use as the oxidant in a PFET system. Studies of photophysical and electrochemical properties, the stability of the Os(III) and Ru(III) complexes, and analytical application in PFET detection of oxidizable analytes are presented. The spectroscopic properties of the complexes were not very advantageous, but careful control of the detection system and reaction conditions enabled sensitive detection of the analytes. The method was fully validated and the optimized system was capable of detecting dopamine and acetaminophen at about 30.2 µg L-1 and 33.5 µg L-1, respectively. The limit of detection (LOD) was 1.5 µg L-1 for acetaminophen and 4.3 µg L-1 for dopamine. The accuracy and precision were within bioanalytical method validation limits (90.9 to 101.5 % and RSD < 12.0 %, respectively). Typical analysis time was less than 15 minutes. Two Fenton-based flow-injection chemiluminescence (CL) methods were developed and validated for the determination of naproxen. Under the optimal experimental conditions the proposed methods exhibited advantages in a larger linear range from 2,760 ng mL-1 to 207,000 ng mL-1 for the first CL method and 41.4 ng mL-1 to 700.0 ng mL-1 for the second CL method. The LOD was 13.8 ng mL-1 for naproxen. The CL mechanisms for the system, H2O2-FeIIEDTA-naproxen was further studied by batch experiments, chemiluminescence spectroscopy, fluorometry, high pressure liquid chromatography (HPLC) and Fourier transform infrared spectroscopy (FTIR). The effects of various interferences commonly found in biological and wastewater systems on the chemiluminescence intensity were also investigated. We used these methods to determine NSAIDs in commercial pharmaceutical formulations. Another application of these method was for detecting NSAIDs in biological samples. A 2x-1-Dimensional Solid Phase Extraction (2x-1D SPE) method was developed for determination of acetaminophen and naproxen in urine. This method uses both the methanol concentration and the pH advantageously to preferentially isolate analytes of interest from complex sample matrix. These methods were fully validated and had sufficient sensitivity (limit of quantification: acetaminophen; 40.41 mg L-1 - 360.0 mg L-1 and naproxen; 23.03 mg L-1 - 214.8 mg L-1) for biological matrices and applications.
Temple University--Theses
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Mohan, Kumar Sreelatha Meera. "Synthèse de complexes cuivreux luminescents." Thesis, Strasbourg, 2012. http://www.theses.fr/2012STRAF068/document.
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La présente thèse décrit la préparation de complexes de Cu(I) stables grâce à l’ingénierie moléculaire de ligands permettant d’éviter la formation de plusieurs espèces en équilibre. Dans le cas de ligands P-N, la stratégie proposée repose sur l’utilisation d’un ligand ayant des substituants permettant de masquer un centre métallique et ainsi d’empêcher les réactions avec des nucléophiles permettant la dissociation du ligand. Dans le cas des dérivés [Cu(NN)(PP)]+, l’approche synthétique développée repose sur l’utilisation de ligands phénanthrolines macrocycliques empêchant la formation des complexes homoleptiques [Cu(NN)2]+ correspondant. Des complexes stables et luminescents ont ainsi été préparés, les rendements quantiques d’émission allant jusqu’à 46% à l’état solide pour les meilleurs luminophoresThe present PhD thesis descibes the preparation of stable Cu(I) complexes through appropriate ligand design to prevent the formation of several species in equilibrium. In the case of dinucleating P,N-ligands, the proposed strategy is based on the use of a ligand with additional substituents to shield the metal centers and thus to prevent nucleophilic attacks leading to ligand dissociation. In the case of the [Cu(NN)(PP)]+ derivatives, the proposed synthetic strategy relies on the use of macrocyclic phenanthroline ligands preventing the formation of the corresponding homoleptic complexes [Cu(NN)2]+. Stable luminescent complexes have been thus prepared, the emission quantum yields being as high as 46% in the solid state for the best emitters
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Oliveira, Handerson Silva Venceslau. "Síntese e caracterização de complexos homonucleares e heteronucleares de lantanídeos e bismuto obtidos a partir de citrato de sódio e 1,10-fenantrolina." Universidade Federal da Paraíba, 2016. http://tede.biblioteca.ufpb.br:8080/handle/tede/9027.
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Homonuclear complexes LnCitnH2O (Ln3+ = Eu3+, Tb3+ and Gd3+) were synthesized by stoichiometric addition of the respective aqueous solutions of the Ln3+ ions under the form nitrate and sodium citrate solution (Na3Cit) at a ratio of 1:1. A complex of formula Bi6O4(OH)4Cit2.2H2O, (M1), was synthesized similarly to the homonuclear complexes Ln3+, wherein the composition obtained was not compatible with the stoichiometry of the starting reactants, i.e., the stoichiometric bismuth/citrate ratio of 1:1. Other bismuth complex, with minima formula BiCit2H2O, (M2), was synthesized by reaction of Na3Cit with Bi(NO3)3 and phen, from the stoichiometric ratio 1:1:1, i.e., citrate, Bi3+ and phen. The complex EuCit.1/2(phen).2H2O (phen = 1,10-phenanthroline) was obtained by reaction between Na3Cit, Eu(NO3)3 and phen with a stoichiometry of the starting reactants in the ratio 1:1:1. Complexes bismuth and lanthanide, heteronucleares, were also synthesized in the ratio 1:1:2, from their respective nitrate salts of Bi3+ and Ln3+ and of the Na3Cit salt. All of these materials were characterized using: atomic graphite furnace absorption spectrophotometry, elemental analysis (CHN), (except for complexes M1 and M2), infrared (IR) spectroscopy and thermal analysis (TG-DTA-DTG). For the EuCit.1/2(phen).2H2O complex, luminescence spectroscopy was also used, which showed high luminescent intensity when irradiated with light of wavelength 350 nm. From the quantitative data of the graphite furnace, elemental analysis (CHN) and thermal analysis techniques, the chemical composition of each complex was suggested and by infrared, coordination forms of the ligands Cit and phen to ions metallics were found. For the heteronuclear complexes, the results of all these techniques indicate structures of the types [LnBi2Cit2.3H2O](H2O)3 ( Ln = Eu3+ and Gd3+ ) and [BiTbCit.2H2O](H2O)3.
Complexos homonucleares LnCit.nH2O (Ln3+ = Eu3+, Tb3+ e de Gd3+ ( n= 1 - 3)) foram sintetizados por adição estequiométrica das respectivas soluções aquosas dos íons de Ln3+, sob a forma nitrato, e da solução de citrato de sódio (Na3Cit), sendo a proporção usada referente às soluções dos reagentes de 1:1. Complexos de bismuto e lantanídeo, heteronucleares, também foram sintetizados a partir dos respectivos sais de nitrato de Bi3+ e Ln3+ e do sal de Na3Cit agora na proporção 1:1:2. Um complexo de fórmula Bi6O4(OH)4Cit2.2H2O, (M1), foi sintetizado de modo semelhante aos dos complexos homonucleares Ln3+, porém, a composição obtida não foi compatível com a estequiometria dos reagentes de partida, ou seja, estequiométrica de 1:1, bismuto / citrato. Outro complexo de bismuto, com fórmula mínima de BiCit.2H2O, (M2), foi sintetizado pela reação de Na3Cit com Bi(NO3)3 e fen, a partir da razão molar 1:1:1, isto é, citrato, ion de bismuto e fen. Também um complexo de európio com composição EuCit.1/2(fen).2H2O (fen = 1,10-fenantrolina) foi obtido pela reação entre Na3Cit, Eu(NO3)3 e fen com uma estequiometria dos reagentes de partida também na proporção de 1:1:1. Todos estes materiais foram caracterizados por: espectrofotometria de absorção utilizando forno de grafite, análise elementar (CHN), (com exceção dos complexos M1 e M2), espectroscopia vibracional na região do infravermelho (FTIR) e análise térmica (TG-DTA-DTG). Para o complexo EuCit.1/2(fen).2H2O espectroscopia de luminescência foi também usada, tendo o mesmo mostrado alta intensidade luminescente quando irradiado com luz de comprimento de onda de 350 nm. A partir dos dados quantitativos de forno de grafite, análise elementar (CHN) e técnicas de análise térmica, a composição química de cada complexo foi sugerida e pelos espectros de infravermelho, as formas de coordenação dos ligantes Cit e fen aos íons metálicos foram também indicadas. Para os complexos heteronucleares, os resultados das três primeiras técnicas indicam estruturas dos tipos [LnBi2Cit2.3H2O](H2O)3 ( Ln = Eu3+ e Gd3+) e [BiTbCit.2H2O](H2O)3.
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TUVERI, ROSSANA. "Identification & characterization of natural and synthetic compounds as new anticancer agents." Doctoral thesis, Università degli Studi di Cagliari, 2016. http://hdl.handle.net/11584/266770.
Full textAbstract:
This thesis collects the work I have done during the three-year PhD Course. During my first
year I have started a path that has allowed me to acquire different techniques devoted to set up
and maintain primary cell cultures and cancer derived cell lines as well as to evaluate the
cytotoxicity of potential novel synthetic inhibitors of human cancer cells. Part of the second and
all the third year was spent at the University of Cape Town, South Africa, in the laboratory of
prof. Ariel Katz under the supervision of proff. Roger Hunter and Catherine H. Kaschula
investigating the anticancer activity of Z-ajoene, a garlic compound.
Overall, the main aim of all the my research project was to identify and characterize natural or
synthetic compounds as new antineoplastic agents. The results obtained are divided according
to the research topics addressed:
Anticancer activity of new Phenanthroline compounds (Part I);
The garlic compound Z-ajoene as anticancer agents (Part II).
Studies referring to the Part have been carried out at the University of Cagliari and were
focalized on the evaluation of new Cu(II) -phenanthroline complexes as a potent antineoplastic
agents against various solid and suspension tumours. The [Cu(1,10-phenanthrolin
-5,6-diol)2(OH2)](ClO4)2 complex appears to be the most potent compound against human
leukemia, prostate and lung cancer cell lines. The results obtained on the biological activity of
this class of compounds, providing valuable information for the design of new anticancer drugs,
have been published in the Journal of Inorganic Biochemistry (2014).
As for the Part II of my research, I focused on the mechanisms underlying the anti-tumoral
activity of garlic compound Z-ajoene on human triple –negative breast cancer cells. The results
indicate that Z-ajoene localizes in the ER of MDA-MB-231 cells where it activates the unfolded
protein response (UPR) and ER stress. These findings have been published in the Molecular
Carcinogenesis journal (2015)
Moreover, immunofluorescence studies support the concept that the Z-ajoene main target is a
ER-resident chaperon protein (PDI), whose functional alteration may well be the cause of the
cytotoxic effect. Another molecular target of Z-ajoene is the cytoskeleton protein Vimentin.
Z-ajoene interacts with Vimentin through a S–thiolation causing the disruption of Vimentin
filaments and therefore an alteration of the cell morphology. Given that Vimentin is known to
participate to the early stage of the metastatic process, I also investigated the potential effect of
Z-ajoene at non-cytotoxic concentrations in a specific cell assay and found that it effectively
inhibits cell migration, both in the absence and presence of a chemotactic agent. The metastatic
inhibition induced by Z-ajoene seems caused by modification of several signaling pathways as
expression of Axl and Src proteins, and phosphorylation of β–catenin were changed. Although
following inhibition of cell migration, a reduction of Vimentin expression was to be expected,
Z-ajoene treatment surprisingly induced an upregulation of Vimentin. We interpreted this result
as a consequence of Z-ajoene binding to Vimentin which unable this protein to perform its
physiologic functions (manuscripts in preparation).
Altogether, the data of my in vitro study indicate that Z-ajoene is a promising chemotherapeutic
agent simultaneously acting on different molecular targets, also able to affect the metastatic
process in cells derived from highly invasive breast tumors. Due to its potential use in the clinic,
preclinical evaluation in xenograft mouse models of cancer are ongoing.
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Kotze, Izak Aldert. "Self-association of [PtII(1,10-Phenanthroline)(N-pyrrolidyl-N-(2,2-dimethyl-propanoyl)thiourea)]+ and non-covalent outer-sphere complex formation with fluoranthene through cation-π interactions : a high resolution 1H and DOSY NMR study." Thesis, Stellenbosch : University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/1796.
Full text
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Shen, Jingyi. "Density functional theory study on the interstitial chemical shifts of main-group-element centered hexazirconium halide clusters; synthetic control of speciation in [(Zr6ZCl12)] (Z = B, C)-based mixed ligand complexes." Diss., Texas A&M University, 2003. http://hdl.handle.net/1969.1/2444.
Full textAbstract:
The correlation between NMR chemical shifts of interstitial atoms and electronic structures of boron- and carbon-centered hexazirconium halide clusters was investigated by density functional theory (DFT) calculation. The influences of bridging halide and terminal ligand variations on electronic structure were examined respectively. Inverse proportionality was found between the chemical shifts and the calculated energy gaps between two Kohn-Sham orbitals of t1u symmetry, which arose from the bonding and antibonding interaction between the zirconium cage bonding orbitals and the interstitial 2p orbitals. Chemical shielding properties of the interstitial atoms were calculated with Gauge Including Atomic Orbital (GIAO) method. Stepwise ligand substitution of terminal chlorides on [(Zr6CCl12)Cl6]4-cluster by tri(n-butyl)-phosphine oxide (Bu3PO) was conducted with the aid of TlPF6. Composition of the reaction mixtures was analyzed by use of both 13C and 31P NMR. A preliminary scheme for synthesis and separation of [(Zr6CCl12)Cl6-x(Bu3PO)x]x-4 (x = 3 ?? 5) mixture based on solubility difference was reevaluated. Three 1,10-phenanthroline based bidentate ligands, namely, 2,9-Bis(diphenyl-phosphinyl)-1,10-phenanthroline, 2,9-Bis(diethoxyphosphoryl)-1,10-phenanthroline, and 2,9-Bis(di-n-butoxyphosphoryl)-1,10-phenantholine, were synthesized for bridge-chelating the hexazirconium clusters. Coordination chemistry of these ligands with the [Zr6BCl12] and [Zr6CCl12] clusters was subject to preliminary investigation.
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Lima, Ana Karina Castro. "Efeito da 1,10-fenantrolina e seus derivados complexados em metal na atividade proteolítica de Leishmania braziliensis." Universidade do Estado do Rio de Janeiro, 2012. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=4604.
Full textAbstract:
Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorLeishmanioses são um grupo de doenças com um largo espectro de manifestações clínicas, as quais variam desde lesões cutâneas até o envolvimento visceral severo, podendo levar ao óbito. A leishmaniose é, ainda hoje, uma doença negligenciada, estando entre os agravos prioritários do programa de pesquisa sobre doenças da pobreza da Organização Mundial da Saúde (OMS). Além de não haver vacinas disponíveis, a terapia é baseada em medicamentos injetáveis que causam sérios efeitos colaterais, tornando o tratamento inviável para muitos países endêmicos. Drogas derivadas de metal representam um novo arsenal terapêutico antimicrobiano e anti-câncer. Os inibidores de peptidase/agentes quelantes tais como 1,10-fenantrolina e seus derivados, no estado livre de metal ou como ligantes com metais de transição, interferem com a função de vários sistemas biológicos. Em trabalhos anteriores, nosso grupo descreveu que o parasito L. braziliensis produziu moléculas gp63 sensíveis a 1,10-fenantrolina. No presente trabalho, demonstramos a distribuição celular da molécula gp63 em uma cepa virulenta de L. braziliensis por meio de análises bioquímicas e imuno-histoquímica. Depois disso, relatamos os efeitos inibitórios de três compostos derivados da 1,10-fenantrolina, 1,10-fenantrolina-5,6-diona (phendio), [Cu(phendio)2] e [Ag(phendio)2], nas atividades metalopeptidases celulares e extracelulares produzidas por promastigotas de L. braziliensis, bem como as suas ações sobre a viabilidade do parasita e na interação com as células de macrófagos murinos. As moléculas gp63 foram detectadas em compartimentos de parasitos, incluindo membrana citoplasmatica e bolsa flagelar. O tratamento de promastigotas de L. braziliensis durante 1 hora com 1,10-fenantrolina e seus derivados resultou numa inibição significativa da viabilidade celular e mostrou um mecanismo de ação irreversível. Estes inibidores de metalopeptidases induziram apoptose em promastigotas de L. braziliensis, demonstrada através da marcação com anexina/iodeto de propídio e ensaio TUNEL. O pré-tratamento de promastigotas com os inibidores de metalopeptidases induziram uma diminuição na expressão de moléculas de superfície gp63, assim como uma redução significativa no índice de associação com macrófagos. Em paralelo, macrófagos infectados com L. braziliensis e tratados com 1,10-fenantrolina e seus derivados promoveram uma potente redução sobre o número de amastigotas intracelulares. O tratamento de macrófagos com 1,10-fenantrolina e seus derivados não induziram o aumento de óxido nítrico. A ação combinatória sobre a capacidade de crescimento entre os compostos derivados da 1,10-fenantrolina e Glucantime, quando ambos foram utilizados em concentracões sub-inibidoras, também foi observada. In vivo os compostos derivados da 1,10-fenantrolina e seus drivados foram capazes de controlar o tamanho das lesões a partir da terceira semana de tratamento em relação ao controle não tratado em hamsters infectados quando administrado por via intraperitoneal. Os animais tratados com os compostos apresentaram maior resposta intradérmica (DTH) aos antígenos de L. braziliensis. Coletivamente, a 1,10-fenantrolina e seus derivados metálicos apresentam uma nova perspectiva de estudos para o desenvolvimento de novos fármacos anti-L. braziliensis
Leishmaniasis is a group of diseases with a wide spectrum of clinical manifestations, which range from self-limited skin lesions to severe visceral involvement that can lead to death. Leishmaniasis is still a neglected disease, and it is among the priorities of the research program on diseases of poverty of World Health Organization (TDR/WHO). There is no available vaccine and the treatment is based on drugs that cause serious side effects, and are unaffordable in several endemic countries. Metal-based drugs represent a novel antimicrobial and anti-cancer therapeutics arsenal. Peptidase inhibitors/chelating agents such as 1,10-phenanthroline and its substituted derivatives, either the metal-free state or as ligands coordinated to transition metals, interfere with crucial functions of several biological systems. In previous works, our group described that L. braziliensis produced gp63 molecules sensible to 1,10-phenanthroline. Herein, we initially studied the cellular distribution of gp63 in a virulent strain of L. braziliensis by biochemical and immunocytochemical analyses. After that, we reported the inhibitory effects of three 1,10-phenanthroline derivative compounds, 1,10-phenanthroline-5,6-dione (phendio), [Cu(phendio)2]and [Ag(phendio)2], on both cellular and extracellular metallopeptidase activities produced by L. braziliensis promastigotes as well as their actions on the parasite viability and on the interaction with murine macrophage cells. The gp63 molecules were detected in several parasite compartments, including cytoplasm, membrane lining the cell body and flagellum, and flagellar pocket. The treatment of L. braziliensis promastigotes for 1 hour with 1,10-phenanthroline and its derivatives resulted in a significant inhibition of cell viability and showed an irreversible mechanism of action. These metallopeptidase inhibitors induced apoptosis in L. braziliensis promastigotes as judged by annexin/propidium iodide staining and TUNEL assays. The pre-treatment of promastigotes with metallopeptidase inhibitors induced a reduction on the expression of surface gp63 as well as a significant reduction on the association index with macrophages. In parallel, the treatment of L. braziliensis-infected macrophages with the 1,10-phenanthroline and its derivatives promoted a powerful reduction on the number of intracellular amastigotes. The treatment of macrophage cells with 1,10-phenantroline and its derivatives did not induce nitric oxide production. A synergistic inhibition on the growth ability was observed when 1,10-phenanthroline derivative compounds and Glucantime were used at sub-inhibitory concentrations. In vivos the compounds 1,10-phenanthroline derivatives and its were able to control the lesions size from the third week of treatment on, when compared to untreated control infected hamsters. The animals treated with the compounds showed greater response to the intradermal antigens of L. braziliensis. Collectively, the 1,10-phenanthroline and its metal-based drugs present a good perspective for prospective studies to the development of new anti-L. braziliensis drugs
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Gueneau, Basile. "Etude et utilisation de complexes polypyridiniques du cuivre (II) dans le cadre de la catalyse de la délignification des pâtes papetières." Thesis, Grenoble, 2012. http://www.theses.fr/2012GRENV023.
Full textAbstract:
L’utilisation de dioxygène lors de la délignification des pâtes à papier permet une réduction considérable des coûts de production et de l’impact environnemental du procédé de blanchiment. Seulement, le taux de délignification est limité par le fait qu’une partie de la lignine résiduelle n’est pas réactive vis-à-vis du dioxygène et que la cellulose est partiellement dépolymérisée au cours du procédé. L’utilisation de catalyseur pourrait permettre d’améliorer l’efficacité et la sélectivité de la délignification au dioxygène comme le suggèrent certaines études. Le complexe cuivre(II)-phénanthroline présente des résultats prometteurs en termes d’efficacité, mais entraîne une dégradation importante de la cellulose. Différents ligands polypyridiniques ont été étudiés dans ces travaux, afin de trouver un complexe du cuivre(II) présentant une affinité forte vis-à-vis de la lignine et faible vis-à-vis de la cellulose. Les complexes formés ont été caractérisés par spectroscopie UV/Vis et voltammétrie cyclique et étudiés comme catalyseurs de l’oxydation de différents substrats : un composé modèle de lignine non phénolique et des substrats lignocellulosiques (un modèle de cellulose, un modèle de lignine native et une pâte kraft industrielle). Les résultats ont montré que la nature même du ligand a un effet important sur l’activité catalytique du complexe de Cuivre (II) lors de l’oxydation du composé modèle de lignine. En revanche, les complexes actifs présentent une activité faible lors de la délignification d’une pâte kraft et oxydent fortement les hydrates de carbone. Ce manque de sélectivité ne permet pas une application pour la production de pâte à papier mais oriente l’utilisation de ce type de catalyseur dans de nouvelles applications n’ayant pas les mêmes contraintes sur le degré de polymérisation de la celluloseDioxygen delignification considerably reduces the operating cost of the bleaching process and decreases the environmental impact of the bleaching effluent. Unfortunately the performance of dioxygen delignification is limited since part of the residual lignin is not reactive toward dioxygen while cellulose depolymerisation occurs. Studies suggested that dioxygen delignification could be improved thanks to the use of catalysts such as copper(II)–phenanthroline type complexes which have shown promising results on delignification efficiency. However cellulose was also more degraded. Different polypyridinyl ligands have been studied in this work, in an attempt to find copper(II) complexes that have more affinity toward lignin and less toward cellulose. Complexes have been characterised by UV/Vis spectroscopy, cyclic volammetry, and they were studied for the catalysed oxidation of various substrates: a non phenolic lignin model compound and lignocellulosic substrates (a model of cellulose, a model of native lignin and an industrial kraft pulp). It has been shown that the nature of the ligand had a significant effect on the catalytic activity of Cu(II) complexes in the oxygen oxidation of the lignin model compound. However, the active complexes only show a limited activity during the delignification of a kraft pulp and oxidize carbohydrates. This lack of selectivity prevents from an industrial application for paper pulp production but may be useful for the design of products with fewer constraints on cellulose polymerization degree
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Elatawy, M. A. K. "SYNTHESIS OF NITROGEN HETEROCYCLES BY INTRAMOLECULAR CYCLIZATION OF ALPHA, BETA-UNSATURATED NITRO COMPOUNDS, CATALYZED BY PALLADIUM COMPLEXES AND WITH CARBON MONOXIDE AS THE REDUCTANT." Doctoral thesis, Università degli Studi di Milano, 2015. http://hdl.handle.net/2434/331319.
Full textAbstract:
This work consists of four main parts.
Part I describes the synthesis of medicinally relevant indoles by palladium-catalyzed reductive cyclization of readily obtainable β-nitrostyrenes using carbon monoxide as the reductant and in acetonitrile as a solvent.
Part II describe a new route to synthesize thieno[2,3-b]pyrrole or thieno[3,2-b]pyrrole by intramolecular reductive cyclization of α,β-unsaturated nitro compounds using carbon monoxide as the reductant and catalyzed by palladium complexes. Part III presents our work on palladium catalyzed intramolecular reductive cyclization of nitro-dienes with carbon monoxide, which provides a novel and efficient method for synthesis of 2,5-disubstituted or 2,3,5-trisubstituted pyrroles.
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Cafe, Peter F. "Towards reliable contacts of molecular electronic devices to gold electrodes." Thesis, The University of Sydney, 2008. http://hdl.handle.net/2123/3870.
Full textAbstract:
SYNOPSIS OF THIS THESIS The aim of this thesis is to more fully understand and explain the binding mechanism of organic molecules to the Au(111) surface and to explore the conduction of such molecules. It consists of five discreet chapters connected to each other by the central theme of “The Single Molecule Device: Conductance and Binding”. There is a deliberate concentration on azine linkers, in particular those with a 1,10-phenanthroline-type bidentate configuration at each end. This linker unit is called a “molecular alligator clip” and is investigated as an alternative to the thiol linker unit more commonly used. Chapter 1 places the work in the broad context of Molecular Electronics and establishes the need for this research. In Chapter 2 the multiple break-junction technique (using a Scanning Tunnelling Microscope or similar device) was used to investigate the conductance of various molecules with azine linkers. A major finding of those experiments is that solvent interactions are a key factor in the conductance signal of particular molecules. Some solvents interfere with the molecule’s interaction with and attachment to the gold electrodes. One indicator of the degree of this interference is the extent of the enhancement or otherwise of the gold quantized conduction peak at 1.0 G0. Below 1.0 G0 a broad range for which the molecule enhances conduction indicates that solvent interactions contribute to a variety of structures which could bridge the electrodes, each with their own specific conductance value. The use of histograms with a Log10 scale for conductance proved useful for observing broad range features. vi Another factor which affects the conductance signal is the geometric alignment of the molecule (or the molecule-solvent structure) to the gold electrode, and the molecular alignment is explored in Chapters 3 for 1,10-phenanthroline (PHEN) and Chapter 4 for thiols. In Chapter 3 STM images, electrochemistry, and Density Functional Theory (DFT) are used to determine 1,10-phenanthroline (PHEN) structures on the Au(111) surface. It is established that PHEN binds in two modes, a physisorbed state and a chemisorbed state. The chemisorbed state is more stable and involves the extraction of gold from the bulk to form adatom-PHEN entities which are highly mobile on the gold surface. Surface pitting is viewed as evidential of the formation of the adatom-molecule entities. DFT calculations in this chapter were performed by Ante Bilic and Jeffery Reimers. The conclusions to Chapter 3 implicate the adatom as a binding mode of thiols to gold and this is explored in Chapter 4 by a timely review of nascent research in the field. The adatom motif is identified as the major binding structure for thiol terminated molecules to gold, using the explanation of surface pitting in Chapter 3 as major evidence and substantiated by emergent literature, both experimental and theoretical. Furthermore, the effect of this binding mode on conductance is explored and structures relevant to the break-junction experiment of Chapter 2 are identified and their conductance values compared. Finally, as a result of researching extensive reports of molecular conductance values, and having attempted the same, a simple method for predicting the conductance of single molecules is presented based upon the tunneling conductance formula.
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Cafe, Peter F. "Towards reliable contacts of molecular electronic devices to gold electrodes." University of Sydney, 2008. http://hdl.handle.net/2123/3870.
Full textAbstract:
PhDSYNOPSIS OF THIS THESIS The aim of this thesis is to more fully understand and explain the binding mechanism of organic molecules to the Au(111) surface and to explore the conduction of such molecules. It consists of five discreet chapters connected to each other by the central theme of “The Single Molecule Device: Conductance and Binding”. There is a deliberate concentration on azine linkers, in particular those with a 1,10-phenanthroline-type bidentate configuration at each end. This linker unit is called a “molecular alligator clip” and is investigated as an alternative to the thiol linker unit more commonly used. Chapter 1 places the work in the broad context of Molecular Electronics and establishes the need for this research. In Chapter 2 the multiple break-junction technique (using a Scanning Tunnelling Microscope or similar device) was used to investigate the conductance of various molecules with azine linkers. A major finding of those experiments is that solvent interactions are a key factor in the conductance signal of particular molecules. Some solvents interfere with the molecule’s interaction with and attachment to the gold electrodes. One indicator of the degree of this interference is the extent of the enhancement or otherwise of the gold quantized conduction peak at 1.0 G0. Below 1.0 G0 a broad range for which the molecule enhances conduction indicates that solvent interactions contribute to a variety of structures which could bridge the electrodes, each with their own specific conductance value. The use of histograms with a Log10 scale for conductance proved useful for observing broad range features. vi Another factor which affects the conductance signal is the geometric alignment of the molecule (or the molecule-solvent structure) to the gold electrode, and the molecular alignment is explored in Chapters 3 for 1,10-phenanthroline (PHEN) and Chapter 4 for thiols. In Chapter 3 STM images, electrochemistry, and Density Functional Theory (DFT) are used to determine 1,10-phenanthroline (PHEN) structures on the Au(111) surface. It is established that PHEN binds in two modes, a physisorbed state and a chemisorbed state. The chemisorbed state is more stable and involves the extraction of gold from the bulk to form adatom-PHEN entities which are highly mobile on the gold surface. Surface pitting is viewed as evidential of the formation of the adatom-molecule entities. DFT calculations in this chapter were performed by Ante Bilic and Jeffery Reimers. The conclusions to Chapter 3 implicate the adatom as a binding mode of thiols to gold and this is explored in Chapter 4 by a timely review of nascent research in the field. The adatom motif is identified as the major binding structure for thiol terminated molecules to gold, using the explanation of surface pitting in Chapter 3 as major evidence and substantiated by emergent literature, both experimental and theoretical. Furthermore, the effect of this binding mode on conductance is explored and structures relevant to the break-junction experiment of Chapter 2 are identified and their conductance values compared. Finally, as a result of researching extensive reports of molecular conductance values, and having attempted the same, a simple method for predicting the conductance of single molecules is presented based upon the tunneling conductance formula.
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Joshi, Hima S. "Conjugated phenanthrolines and metal-containing DNA as luminescent probes /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2001. http://wwwlib.umi.com/cr/ucsd/fullcit?p3007141.
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