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1
Merkel, Roswitha. "Untersuchung zur Synthese und Eigenschaften von komplexen Oligospiroketalen." Phd thesis, Universität Potsdam, 2014. http://opus.kobv.de/ubp/volltexte/2015/7256/.
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Es ist in dieser Arbeit gelungen, starre Oligospiroketal(OSK)-Stäbe als Grundbausteine für komplexe 2D- und 3D-Systeme zu verwenden. Dazu wurde ein difunktionalisierter starrer Stab synthetisiert, der mit seines Gleichen und anderen verzweigten Funktionalisierungseinheiten in Azid-Alkin-Klickreaktionen eingesetzt wurde.
An zwei über Klickreaktion verknüpften OSK-Stäben konnten mittels theoretischer Berechnungen Aussagen über die neuartige Bimodalität der Konformation getroffen werden. Es wurde dafür der Begriff Gelenkstab eingeführt, da die Moleküle um ein Gelenk gedreht sowohl gestreckt als auch geknickt vorliegen können.
Aufbauend auf diesen Erkenntnissen konnte gezeigt werden, dass nicht nur gezielt große Polymere aus bis zu vier OSK-Stäben synthetisiert werden können, sondern es auch möglich ist, durch gezielte Änderung von Reaktionsbedingungen der Klickreaktion auch Cyclen aus starren OSK-Stäben herzustellen.
Die neu entwickelte Substanzklasse der Gelenkstäbe wurde im Hinblick auf die Steuerung des vorliegenden Gleichgewichts zwischen geknicktem und gestrecktem Gelenkstab hin untersucht. Dafür wurde der Gelenkstab mit Pyrenylresten in terminaler Position versehen. Es wurde durch Fluoreszenzmessungen festgestellt, dass das Gleichgewicht z. B. durch die Temperatur oder die Wahl des Lösungsmittels beeinflussbar ist.
Für vielfache Anwendungen wurde eine vereinfachte Synthesestrategie gefunden, mit der eine beliebige Funktionalisierung in nur einem Syntheseschritt erreicht werden konnte.
Es konnten photoaktive Gelenkstäbe synthetisiert werden, die gezielt zur intramolekularen Dimerisierung geführt werden konnten.
Zusätzlich wurde durch Aminosäuren ein Verknüpfungselement am Ende der Gelenkstäbe gefunden, das eine stereoselektive Synthese von Mehrfachfunktionalisierungen zulässt.
Die Synthese der komplexen Gelenkstäbe wurde als ein neuartiges Gebiet aufgezeigt und bietet ein breites Forschungspotential für weitere Anwendungen z. B. in der Biologie (als molekulare Schalter für Ionentransporte) und in der Materialchemie (als Ladungs- oder Energietransporteure).In this dissertation the use of rigid Oligospiroketal (OSK)-rods as basic model for 2D- and 3D-systems was shown. For that purpose a bifunctionalized rigid rod was synthesized and was used in Azide-Alkine-clickreaction with itself and with other branched functionalized units. By theoretical calculations a statement about the novel bimodulation of the conformation of two OSK-rods which are linked by a clickreaction could be made. “Articulated rod” was introduced as new term, because the molecules could exist elongated or buckled. Based on this knowledge it became apparent that not only the size selective synthesis of polymers by using up to four OSK-rods is possible but also cycles with OSK-rods by using different click-reaction conditions can be synthesized. The newly developed group of “articulated rod” substances was examined regarding the equilibrium between buckled and elongated “articulated rod”. That for the articulated rod was functionalized with pyrenyl moieties in terminal position. By fluorescence measurements of these rods it could be shown that the equilibration is influenced by different temperatures and different solvents. For multiple applications a simplified strategy for synthesis with a wide range of functionalization in only one step of synthesis could be achieved. Photoactive articulated rods were synthesized, that could be selectively intramolecular dimerized. Additionally, amino acids were introduced as linker at the end of a articulated rod. By this a stereoselective synthesis of multiple functionaliations is possible. By the synthesis of complex articulated rods a novel field of research was found. There is a wide potential of research for more applications for example in biology (as molecular switch for transportation of ions) and in materials chemistry (as transporter for charge or energy).
2
Okumu, Antony A. "Development of a Safe and Efficient Alkyl Azide Synthesis using Arylsulfonyl Azide." Youngstown State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1290962115.
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Mackay, Fiona S. "Photoactive platinum azide anticancer complexes." Thesis, University of Edinburgh, 2006. http://hdl.handle.net/1842/11085.
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Photoactive platinum compounds have the potential to reduce some of the debilitating side-effects associated with conventional chemotherapeutics, such as cisplatin. Stable, inert platinum(IV) compounds which are reduced to active platinum(II) species only upon irradiation, could provide a site-specific treatment. The PtIV azide complexes, cis, trans, cis-[Pt(N3)2(OH)2(NH3)2] and cis, trans-[Pt(en)(N3)2, have previously been shown to be stable in the dark but reduced to PtII upon irradiation. The synthesis and characterisation of new platinum azide compounds, designed to improve important properties such as solubility and wavelength of absorbance are described here. Complexes which have azide ligands in a trans position were synthesised, the general formula is trans, trans, trans-[Pt(N3)2(OH)2(NH3)R] where R is NH3, pyridine, methylamine, ethylamine, thiazole, 2-picoline, 3-picoline, 4-picoline or cyclohexylamine. Several PtIV diazido compounds containing chelating aromatic ligands, such as 2,2’-bipyridine and 1,10-phenanthroline were also prepared. Many of the novel compounds synthesised were characterised by X-ray structure determination. The complexes with trans azides generally showed improved water solubility as well as a shift of the main absorbance band towards the visible region, compared to their cis analogues. A transcription mapping study of a fragment of pSP73KB plasmid DNA treated with cis, trans-[Pt(en)(N3)2(OH)2] and visible light, has shown that platination mainly occurs at consecutive guanine bases. The major binding sites were similar to those of cisplatin. No platination was seen in an identical sample which was not irradiated.
4
Bolton, R. E. "Azide decomposition in natural product synthesis." Thesis, Imperial College London, 1986. http://hdl.handle.net/10044/1/37947.
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Wong, Sang K. "Pharmaceutical studies on aromatic azido compounds." Thesis, Aston University, 1986. http://publications.aston.ac.uk/12461/.
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Dang, Thao P. "Biomimetic Modeling of the Nitrogen-centered Radical Postulated to occur during the Inhibition of Ribonucleotide Reductases by 2'-Azido-2'-deoxynucleotides." FIU Digital Commons, 2010. http://digitalcommons.fiu.edu/etd/318.
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Ribonucleotide reductases (RNR) are essential enzymes that catalyze the reduction of ribonucleotides to 2'-deoxyribonucleotides, which is a critical step that produces precursors for DNA replication and repair. The inactivation of RNR, logically, would discontinue producing the precursors of the DNA of viral or cancer cells, which then would consequently end the cycle of DNA replication. Among different compounds that were found to be inhibitors of RNR, 2'-azido-2'-deoxynucleotide diphosphates (N3NDPs) have been investigated in depth as potent inhibitors of RNR. Decades of investigation has suggested that the inactivation of RNR by N3NDPs is a result of the formation of a nitrogen-centered radical (N•) that is covalently attached to the nucleotide at C3' and cysteine molecule C225 [3'-C(R-S-N•-C-OH)]. Biomimetic simulation reactions for the generation of the nitrogen-centered radicals similar to the one observed during the inactivation of the RNR by azionuclotides was investigated. The study included several modes: (i) theoretical calculation that showed the feasibility of the ring closure reaction between thiyl radicals and azido group; (ii) synthesis of the model azido nucleosides with a linker attached to C3' or C5' having a thiol or vicinal dithiol functionality; (iii) generation of the thiyl radical under both physiological and radiolysis conditions whose role is important in the initiation on RNR cascades; and (iv) analysis of the nitrogen-centered radical species formed during interaction between the thiyl radical and azido group by electron paramagnetic resonance spectroscopy (EPR). Characterization of the aminyl radical species formed during one electron attachment to the azido group of 2'-azido-2'-deoxyuridine and its stereospecifically labelled 1'-, 2'-, 3'-, 4'- or 5,6-[2H2]-analogues was also examined. This dissertation gave insight toward understanding the mechanism of the formation of the nitrogen-centered radical during the inactivation of RNRs by azidonucleotides as well as the mechanism of action of RNRs that might provide key information necessary for the development of the next generation of antiviral and anticancer drugs.
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Schöffler, Claudia. "Propargylazide als Ausgangsmaterialien für Umlagerungsreaktionen und Heterocyclensynthesen." [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=964562138.
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Firdous, Samia. "Synthesis and Reactions of α-Azido Alcohols." Doctoral thesis, Universitätsbibliothek Chemnitz, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-86012.
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Die vorliegende Arbeit beschäftigt sich mit der Untersuchung von a-Azidoalkoholen, welche über die Reaktion von aliphatischen sowie aromatischen Aldehyden mit HN3 leicht zugänglich sind und die im Gleichgewicht mit den jeweiligen Ausgangsstoffen vorliegen. Bei Raumtemperatur stellt sich dieses Gleichgewicht sehr schnell ein und man erhält spezifische Konzentrationen an Eduktaldehyd, Stickstoffwasserstoffsäure und a-Azidoalkohol. Die Reaktion von Aldehyden mit HN3 generiert dabei ein neues Chriralitätszentrum, wodurch die Umsetzung chiraler Aldehyde, wie z. B. von Zuckerderivaten, zwei anomere Produkte hervorbringt. Die erstmalig erfolgreichen Synthesen zur Erzeugung von 4-Brom-4-methylpentanal sowie 4-Azido-4-methylpentanal werden ebenfalls beschrieben. Letztere Verbindung reagiert dabei ebenso wenig via einer intramolekularen 1,3-dipolaren Cycloaddition zum entsprechenden 4,5-Dihydro-1,2,3,4-oxatriazol-Derivat wie das analoge-Azidobutanal, was im Gegensatz zu Literaturangaben steht. Des Weiteren werden einige interessante Reaktionen der a-Azidoalkohole untersucht. Die Oxidation mit Pyridiniumchlorochromat (PCC) bei –60°C führt zu Carbonylaziden. Die Photolyse bei –50°C generiert unter Stickstofffreisetzung Nitrene, welche mittels Wasserstoffwanderung und anschließender Tautomerisierung des resultierenden Intermediats zu Säureamiden umlagern. Die ebenfalls mögliche 1,2-Wanderung einer Gruppe R in a-Position führt dabei zu einem Intermediat, aus welchem sofort das entsprechende Formamid-Derivat entsteht. a-Azidoalkohole reagieren mit PBr3 in einer sauberen Reaktion durch die Substitution der Hydroxylfunktion unter Bildung der jeweiligen 1-Azido-1-brom-VerbindungIn this work, α-azido alcohols which exist in equilibrium with the starting materials have been studied by the reactions of aliphatic and aromatic aldehydes with HN3. In some cases the title compounds can be isolated from the mixture at low temperature. At room temperature, however, the equilibrium is fast and there are again specific concentrations of the aldehyde, hydrazoic acid, and the α-azido alcohol. The reaction of aldehydes with HN3 creates a new chiral center and a chiral aldehyde, e.g. sugar derivatives, produces two anomeric products. The first procedures to prepare 4-bromo-4-methylpentanal and 4-azido-4-methylpentanal are also reported. The latter compound and also the parent 4-azidobutanal do not lead to 4,5-dihydro-1,2,3,4-oxatriazoles by intramolecular 1,3-dipolar cycloaddition, although it was claimed in the literature. Furthermore, some interesting reactions of the α-azido alcohols have been investigated. The oxidation of α-azido alcohols with pyridinium chlorochromate (PCC) at −60 °C leads to formation of carbonyl azides. The photolysis of α-azido alcohols at −50 °C generates nitrenes with liberation of dinitrogen, which lead to the formation of acid amides after the migration of hydrogen and subsequent tautomerism of the intermediate. 1,2-Migration of a group R in the α-position can produce an intermediate stage which is rapidly converted into formamide derivative. α-Azido alcohols react with PBr3 to give 1-azido-1-bromo derivatives in a clean reaction by substitution of hydroxyl group at the α-position
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Canbolat, Eylem. "Organocatalytic Resolution Of Racemic Alpha Azido Ketones." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614602/index.pdf.
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Chiral cyclic alpha azido ketones are very important compounds in organic chemistry. Because, the reduced forms of them are amino alcohols and these amino alcohols are interesting compounds for their biological activities. They have some pharmaceutical activities such as: potassium channel open up properties, treatment of central nervous system, antihypertensive properties, the agent of dopamin receptor activator, hypolipemic agent and dopamine agonist. These types of compounds have highly acidic alpha-protons, and many kinds of reactions can be performed with them. In this study, mainly, selective protonation of racemic compounds was performed with a new practical method and there are not so many examples related to deracemization in the literature. Alpha-azido derivatives of tetralone, indanone, chromanone, and thiochromanone structures are chosen as starting materials because of their importance for biological activities arising from their cyclic structures. Firstly, these &alpha-azido compounds were synthesized according to literature. The acidic alpha-protons do not require strong bases. Their enantioselective deracemization and deracemization processes were screened by using Cinchona derivatives as organocatalysts. This screening process was monitored by chiral HPLC columns. The parameters such as catalyst loading, solvent, temperature, reaction time and additives were optimized to obtain high enantioselectivities up to 98%. In addition to deracemization reactions, Michael addition reactions were also performed by starting from &alpha
-azido chromanones. In these reactions different type of urea catalyst was used to activate the electrophilic part of trans-&beta
-nitrostyrene compound. Again by controlling the temperature, time and catalyst loading, two diastereomers were formed and the screening process was monitored by chiral HPLC columns again. The Michael products were obtained in up to 94% ee and 75% yield.
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Wutke, Jens. "Synthesen und Reaktionen von Ethinylaziden." Doctoral thesis, Universitätsbibliothek Chemnitz, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-61560.
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Gegenstand der vorliegenden Arbeit sind Versuche zur Synthese von 1-Azido-1 alkinen (Ethinylaziden). Diese instabilen Verbindungen zersetzen sich leicht unter Stickstoffabspaltung zu hochreaktiven Carbenen, welche mit verschiedenen Reagenzien, explizit Tolan, Cyclooctin, DMSO sowie DMF, abgefangen werden konnten. Obwohl eine direkte spektroskopische Beobachtung der Titelverbindungen mittels Tieftemperatur-NMR-Spektroskopie nicht verwirklicht werden konnte, gelang der eindeutige Nachweis von Ethinylaziden via deren 1,3-dipolarer Cycloaddition mit dem hochgespannten cyclischen Alkin Cyclooctin. Als Strategie für die Synthese der Titelverbindungen wurden sowohl Substitutionsreaktionen ausgehend von (Chlorethinyl)aromaten als auch Eliminierungsreaktionen ausgehend von substituierten Vinylaziden herangezogen. Es konnten zahlreiche Sulfoxonium-Ylide sowie alpha-Oxocarbonsäureamide als eindeutige Folgeprodukte der Titelverbindungen isoliert und vollständig – größtenteils sogar anhand von Röntgeneinkristallstrukturanalysen – charakterisiert werden.
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Aubauer, Christoph. "Halogen-, Azid- und Koordinationsverbindungen des Phosphors." Diss., [S.l.] : [s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=963037900.
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Seoane, Gustavo A. "Synthesis of pyrrolizidine diols via azide-diene cycloadditions." Diss., Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/81012.
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The generality of the [4+1] annulation methodology in the context of natural product synthesis was demonstrated by extending its applicability to the heteroatom (nitrogen) case thus allowing access to the alkaloid field. This novel methodology involved the intramolecular union of a hypovalent nitrogen atom equivalent and a conjugated diene to afford a pyrroline ring. The flexibility of this strategy was exemplified by the formal synthesis of ring-A oxygenated pyrrolizidine alkaloids platynecine 8, turneforcidine 9, hastanecine 10, and dihydroxyheliotridane 11.
The key features of this technology involved preparation of azidodiene ill, its cyclization, via the intermediate triazoline which was not isolated, to vinylaziridines 234, and the vinylaziridine-pyrroline rearrangement of several derivatives of 234 to pyrrolizidines 239, 241, and 242. A study of the thermal decomposition of oxygenated azidodienes such as 196 and 233 was carried out. Conclusive results regarding the stereochemical control of the C-7 substituent were attained and used for the formal stereospecific syntheses of pyrrolizidinediols 8, 9, 10, and 11.
The possibility of asymmetric induction was also investigated, and was realized in the microbial reduction of only one of the enantiomers of alcohol ill protected as ester 248, providing potential access to either enantiomeric series of pyrrolizidine diols.
[see document for diagram of chemical reaction]Ph. D.
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Copeland, Christopher N. II. "Modified Conditions for Acyl Azide and Carbamate Synthesis." Youngstown State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1473765784542178.
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Banert, Klaus. "Umlagerungen organischer Azide : Reaktionsmechanismen und Anwendungen in der Synthese /." Rheinfelden [etc.] : Schäuble, 1993. http://opac.nebis.ch/cgi-bin/showAbstract.pl?u20=3877189083.
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Sofin, Mikhail. "Neue Alkalioxometallate über die Azid/Nitrat-Route." [S.l. : s.n.], 2003. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB11051832.
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Silva, Mauro Vinícius Almeida da. "Modificação química do poli(cloreto de vinila) com nucleófilos nitrogenados assistida por micro-ondas." Universidade do Estado do Rio de Janeiro, 2013. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=4844.
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Conselho Nacional de Desenvolvimento Científico e TecnológicoNesse trabalho foram realizadas reações de substituição nucleofílica (SN2), utilizando aquecimento térmico convencional e por irradiação de micro-ondas (MO), de alguns átomos cloro em amostras comerciais de poli(cloreto de vinila) (PVC), por grupos nitrila e também por grupos azida. Os grupos nitrila e azida foram substituidos na matriz em diferentes teores (10% e 20%). As reações do PVC com azida foram eficazes, apresentado percentuais de derivatização muito próximos dos valores desejados. Já no estudo com a nitrila não foi obtido o resultado esperado. Os copolímeros PVC azido substituídos foram modificados com propargilato de etila, sob catálise de iodeto de cuproso (CuI), para a obtenção de heterocíclicos do tipo triazólicos. Todos os copolímeros obtidos foram caracterizados por espectroscopia na região do infravermelho (FTIR) e os teores de nitrogênio incorporado foram determinados por análise elementar (AE). Através da análise dos dados obtidos, foi comprovado que a utilização da irradiação micro-ondas, quando comparada ao aquecimento convencional, é um processo mais seletivo e diminui, significativamente, os tempos de reação
In this work we had performed nucleophilic substitution reactions (Sn2) of some chlorine atoms in commercial samples of poly (vinyl chloride) (PVC), nitrile groups and also by azide groups, using both conventional thermal heating and microwave irradiation (MW).Nitrile and azide groups were replaced in the matrix at diverse levels (10% and 20%). The reactions of PVC with azide were effective, reaching a percentage derivatization very near to the desired values. In the study with the nitrile although we have not obtained the expected results. The substituted azido copolymers were modified with propargilato acetate, under catalysis of copper iodide (CuI) to obtain triazole heterocyclic type. All copolymers were labeled by infrared spectroscopy (FTIR) and nitrogen contents were determined by corporate elemental analysis (EA). Through analysis of the data obtained, it was verified that the use of microwave irradiation in comparison to conventional heating is a more selective process and reduces significantly reaction times
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Davis, Edward A. "Studies of sodium azide with tetraphenylcyclopentadienones and various analogs." Thesis, Virginia Tech, 1985. http://hdl.handle.net/10919/45676.
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The reaction of sodium azide with 2-p-chloro- and 2-pâ methoxyphenylâ 3,4,5-triphenylâ 2,4-cyclopentadienâ Iâ one was studied to determine if the substituent would have any appreciable effect on the product distribution of the corresponding l,5,7,8â tetraphenyl-2,3,4â triazabicyclo[3.3.0]octa-2,7-dien-6-ones and the 3,4,5,6â tetraphenylâ 2(lH)â pyridinones that were formed by an acid catalyzed rearrangement. It was found that the chloro substituent had no effect on the reaction. The methoxy substituent had a moderate effect in that the product arising from the stabilized intermediate cation was favored by a ratio of approximately 3 to l.
The two simple linear analogs studied were l,2,3,3â tetraphenyl-2- propen-l-one and 3,4,4-triphenyl-3â butenâ 2â one. These compounds did not react with azide, presumably due to charge delocalization. Also studied as a cyclic analog was 2,7-diphenyltropone which did not react due to the aromatic character of the tropone ring system. A reaction did occur with diphenylcyclopropenone to give an unidentified product. However, the reaction did not take place in the same fashion as for the tetracyclones.
Master of Science
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Habimana, Jean de la Croix. "Fonctionnalisation directe en polymérisation cationique : synthèse d'oligoisobutène azido-téléchélique." Grenoble INPG, 1989. http://www.theses.fr/1989INPG0016.
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Adero, Philip O. "Heterocycle Synthesis via Rhodium (II)-Catalyzed Azido Carbenoid Cyclization." Youngstown State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1348595887.
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Young, Mary Jennifer T. "The photochemistry of pentafluorophenyl azide and its transient intermediates /." The Ohio State University, 1988. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487596307356436.
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Maciej, Marissa Lucy. "Azido sugars for the modification of glycosaminoglycans in biology." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/azido-sugars-for-the-modification-of-glycosaminoglycans-in-biology(cf34d9aa-d20b-4225-b871-93a5983832b6).html.
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Heparan sulphate (HS) is critical for embryonic development with involvement in a myriad of biological processes, centrally mediating morphogenic movements and facilitating the specification and differentiation of tissues. Complicated by its structural micro-heterogeneity along with expression on numerous different proteoglycan cores, the plethora of roles for HS in biology and their underlying mechanisms have not yet been fully defined. The discovery and characterisation of new reagents and methods for modification of HS expression and/or structure will aid efforts in elucidating the structure and activity of this glycosaminoglycan. Until now, azido sugars have been utilised as labelling reagents for various types of glycosylation, including N-glycans, O-linked mucin-type glycosylation and O-GlcNAcetylation of proteins. Incorporation of the unnatural azido sugar into the glycan of interest inserts a chemically reactive abiotic azide for subsequent detection via Staudinger ligation or click chemistries. However, to our knowledge, application of these azido sugars has not been explored for glycosaminoglycans. A metabolic labelling approach using Ac4GalNAz yields UDP-GalNAz and UDP-GlcNAz (Boyce et al., 2011), ready to target CS/DS and HS, respectively. We hypothesised that HS synthesis might be altered in the presence of UDP-GlcNAz due to the location of the azide on the acetyl group and the potential for interference with endogenous N-deacetylase-N-sulphotransferase biosynthetic enzyme activity. In mammalian cell culture (Chinese hamster ovary cells), treatment with Ac4GalNAz led to a decrease in total HS abundance accompanied by significant increases in 6-O-sulphation within the chains. Incorporation of a radiolabelled metabolic precursor revealed that average HS chain length was decreased in azido sugar-treated CHO cells. The modifications to HS were dose-dependent and HS inhibition was transient. Following removal of Ac4GalNAz from cell culture, HS expression returned to baseline levels within 24 hours. Previous work from the Bertozzi group has demonstrated the utility of Ac4GalNAz for visualising GalNAc- and O-GlcNAc-modified proteins in vivo. Using Xenopus, we were able to show that treatment of fertilised eggs with Ac4GalNAz decreased the abundance of HS in a similar way to that seen in vitro, with an associated impact on embryonic development. Embryonic axial elongation was impaired, with defective myotomal development and aberrant axonal patterning along the trunk and tail. Posterior somite cell nuclei were disorganised, with loss of distinct chevron patterning and skeletal muscle development was impaired with muscle fibres spanning some of the somite boundaries. Removal of the inhibitor partially rescued tail extension defects, as well as muscle development, but not axonal patterning. Therefore, these experiments illustrate a novel application for Ac4GalNAz as a soluble and reversible inhibitor of HS synthesis for in vitro and in vivo studies. The observed potential for control of inhibition via time- and dose-dependent effects enables targeted and selective inhibition of HS and potentially provides a powerful new inhibitor for the study of HS-mediated events.
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Wells, Sheryl McGaha Walker Robert Harold. "Granular forms of sodium and potassium azide as a nematicide for established turfgrasses." Auburn, Ala, 2009. http://hdl.handle.net/10415/1712.
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Long, Brian D. "A mechanistic study of the solution thermolysis of 2-azidodiphenylmethanes." Thesis, Keele University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.279920.
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Schütt, Thomas. "Halogen-, Azid- und Koordinationsverbindungen des Arsens und Antimons." Diss., lmu, 2001. http://nbn-resolving.de/urn:nbn:de:bvb:19-3668.
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Schütt, Thomas. "Halogen-, Azid- und Koordinationsverbindungen des Arsens und Antimons." [S.l.] : [s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=963037811.
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Aronson, Joshua Boyer. "The Synthesis and Characterization of Energetic Materials From Sodium Azide." Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/7597.
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A tetrazole is a 5-membered ring containing 4 nitrogens and 1 carbon. Due to its energetic potential and structural similarity to carboxylic acids, this ring system has a wide number of applications. In this thesis, a new and safe sustainable process to produce tetrazoles was designed that acheived high yields under mild conditions. Also, a technique was developed to form a trityl-protected tetrazole in situ. The rest of this work involved the exploitation of the energetic potential of tetrazoles. This moiety was successfully applied in polymers, ionic liquids, foams, and gels. The overall results from these experiments illustrate the fact that tetrazoles have the potential to serve as a stable alternative to the troublesome azido group common in many energetic materials. Due to these applications, the tetrazole moiety is a very important entity.
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Organtzis, Stefanos. "Polynuclear transition metal complexes containing azido and pyrazolinato bridging ligands." Thesis, University of Manchester, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.496513.
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Following the discovery that a single molecule can behave as a magnet, the field of research on magnetism has become of great interest to scientists. A large number of polynuclear compounds have been produced and studied worldwide over the past two decades, in an effort to obtain better single molecule magnets (SMMs). The synthesis of such compounds involves mainly first row transition metals and a wide range of bridging ligands.
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Link, Aaron James Tirrell David A. "Azide-bearing amino acids in protein engineering and proteomic profiling /." Diss., Pasadena, Calif. : Caltech, 2006. http://resolver.caltech.edu/CaltechETD:etd-09132005-120123.
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Zhang, Jianjun. "Library Synthesis of Anticancer and Antibacterial Agents via Azide Chemistry." DigitalCommons@USU, 2010. https://digitalcommons.usu.edu/etd/711.
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Various anticancer and antibacterial agents have been synthesized via azide chemistry by taking advantage of carbohydrate. Starting from the synthesis of 14 glycosyl azides, a library of carbohydrate-oxazolidinone conjugates and a library of carbohydrate-cyclopamine conjugates with biological interests were synthesized based on a highly efficient "click reaction" assisted by sonication. Some of the conjugates have improved solubility and enhanced anticancer activity. A library of neomycin B derivatives with various modifications at the 5" position has been synthesized. Two leads exhibit prominent activity against both methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). Antibacterial activities were measured when combined with other clinically used antibiotics and significant synergistic activities were observed. Three different classes of aryl N-glycosides have been synthesized by employing 1,4-naphthoquinone and glycosyl azides undergoing a [2+3] cycloaddition. Alkyl azides can also undergo the same cycloaddition. After the removal of the protecting group, a library of 9,10-anthraquinone derivatives with potential anticancer activity and a library of 2-aminomethylene-1,3-indanediones with novel antibacterial activity have been developed, respectively. A one-pot three-component [2+3] cycloaddition for the synthesis of 1-alkyl 1H-naphtho[2,3-d][1,2,3]triazole-4,9-dione and 2-alkyl 2H-naphtho[2,3-d][1,2,3] triazole-4,9-dione has been developed. By taking the advantage of their difference in basicity, both products can be obtained in good purity. Using an allylic azide rearrangement, a convenient method has been developed for the synthesis of several 2',3'-dideoxyaminoglycosides. The antibacterial activity of these novel aminoglycosides also confirms the indispensable role of the 2'-NH2 group for both neomycin and kanamycin classes of aminoglycosides. A novel structural motif containing the hexylaminocarbonyl groups at O-5 and/or O-6 of 2',3'-dideoxyneamine could lead to the production of new aminoglycosides against resistant bacteria.
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Beveridge, Jennifer Marie. "Copper(I)-catalyzed azide-alkyne cycloaddition with membrane bound lipid substrates." Thesis, Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/53594.
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The bioorthogonal copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) reaction exhibits complex but well-defined kinetics in aqueous and organic solution for soluble azides, alkynes, and ligand-bound copper(I). The kinetic profile in two dimensions, however, for CuAAC systems within a lipid bilayer membrane, has yet to be defined. The effect of triazole formation with lipid membrane-bound components on membrane properties such as fluidity and permeability is also of interest. Azide- and alkyne-functionalized lysolipids were synthesized and incorporated into non-fluid vesicles, which were then subject to CuAAC. The rate order for membrane-bound lipid substrates in non-fluid vesicles was observed to be comperable to that of the reaction in solution. Reactions between vesicles showed evidence of lipid transfer between non-fluid membranes, which has not been previously reported. For intervesicular and intravesicular reactions in non-fluid membranes, the observed reactivity was found to be opposite that of previously published reactions between nucleophiles and electrophiles in fluid lipid systems. Applications of this work include the potential for novel symmetric membrane leaflet labeling, bioorthogonal manipulation of cell and tissue function, and the creation of membranes with precisely controlled properties that may not be available in naturally-occurring membranes.
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Gramlich, Philipp Mathias Edwin. "Selective DNA modification using the Cu(I)-catalyzed alkyne-azide cycloaddition." Göttingen Cuvillier, 2008. http://d-nb.info/990811395/04.
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Brittain, William David George. "Asymmetric synthesis 1,2,3-triazoles utilising the copper-catalysed azide-alkyne cycloaddition." Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8143/.
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The copper-catalysed azide-alkyne cycloaddition (CuAAC) is a highly efficient reaction and is the cornerstone of “click” chemistry. However, unlike many common metal-mediated transformations asymmetric CuAAC variants are relatively sparse. This thesis details asymmetric “click” reactions with Chapter 1 introducing the CuAAC and the asymmetric variants already present in the literature. Chapter 2 outlines research demonstrating the first example of kinetic resolution of an alkyne via a CuAAC reaction. Selectivity factors of up to 22.1 ± 0.5 were obtained and triazoles and alkynes were obtained in ≤ 80% enantiomeric excess (ee). This chapter also contains a study on the simultaneous kinetic resolution of azides and alkynes; azides were obtained in >30% \(e\)\(e\), alkynes in >40% \(e\)\(e\) and a triazolic diastereomeric product was obtained in up to 90% \(e\)\(e\). In Chapter 3 the Bull-James three-component boronic acid assembly is successfully employed for the kinetic resolution of primary amine alkynes with selectivity factors of up to 4.1 obtained. The principle behind the assembly is also elaborated upon in this chapter leading to its use in both dynamic combinatorial chemistry and as a pedagogical tool. Chapter 4 details work on atropisomerism in triazolic systems. A series of novel triazoles, iodotriazoles and triazolium salts were successfully synthesised and their atropisomeric stability probed. Chapter 5 presents feasibility studies towards the asymmetric synthesis of 5,5’-bis(triazoles) and ruthenium olefin metathesis catalysts in the formation of 1,5-triazoles.
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Evangelista, Fernanda Cristina Gontijo. "Evaluation of in vitro antitumor activity of triazole / azide synthetic chalcones." Instituto Nacional de Pesquisas da Amazônia, 2018. http://bdtd.inpa.gov.br/handle/tede/2639.
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Fundação de Amparo à Pesquisa do Estado de São Paulo - FAPESP
Many compounds isolated from lichens exhibit biological activity, and a number of them are proven sources of antitumor drugs. Even simple structural changes to these bioactive compounds can lead to potentiation of their activity. The purposes of this study were to evaluate the antiproliferative activity and selectivity of the following compounds isolated from lichens: atranorin; diffractaic, divaricatic, perlatolic, psoromic, norstitic, protocetraric, and fumarprotocetraric acids; and alkyl derivatives. Cytotoxicity tests based on the sulforhodamine B dye were performed on seven lines of neoplastic cells and one line of normal cells (3T3)
Muitas substâncias isoladas de liquens apresentam atividades biológicas, e algumas demonstraram ser fontes promissoras de drogas antitumorais. Modificações estruturais simples a partir dessas substâncias bioativas podem levar a potencialização da atividade apresentada. Os objetivos deste estudo foram avaliar a atividade antiproliferativa e seletividade dos seguintes compostos isolados de liquens: atranorina, ácidos difractaico, divaricático, perlatólico, psorômico, norstítico, protocetrárico e fumarprotocetrárico e derivados alquílicos. O ensaio de citotoxicidade foi realizado com corante sulforrodamina B em sete linhagens de células neoplásicas e uma linhagem de células normais (3T3)
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Jagerovic, Nadine. "Réactivité de complexes azido en série métalloporphyrinique : synthèses et études spectroscopiques." Dijon, 1990. http://www.theses.fr/1990DIJOS049.
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Curry, Omadee S. "Reaction of o-Nitrobenzenesulfonyl Azide/n-Butyl Lithium with Hindered Alcohols." Youngstown State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1379945812.
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Scheubeck, Thomas Josef. "Beiträge zur strukturchemischen Untersuchung von Wasserstoffbrückenbindungen in ammoniakhaltigen Aziden, Amiden und Ammoniumsalzen." kostenfrei, 2009. http://www.opus-bayern.de/uni-regensburg/volltexte/2009/1308/.
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Sirivolu, Venkata Ramana. "DNA containing side chains with terminal triple bonds: Synthesis, base pairing and functionalization of nucleosides and oligonucleotides by the azide-alkyne cycloaddition = DNA mit Terminalen Dreifachbindungen in Seitenketten: Synthese, Basenpaarung und Funktionalisierung von Nucleosiden und Oligonucleotiden durch die Azid-Alkin Cycloaddition /." Osnabrück, 2008. http://opac.nebis.ch/cgi-bin/showAbstract.pl?sys=000254558.
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Mannuthodikayil, Jamsad [Verfasser]. "Chemical tools for bioconjugation : Application of the thioacid-azide ligation / Jamsad Mannuthodikayil." Konstanz : Bibliothek der Universität Konstanz, 2015. http://d-nb.info/1100392319/34.
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Tolland, John Douglas. "Stopped-flow infrared spectroscopy of carbon monoxide and azide reduction by nitrogenase_â’¸." Thesis, University of East Anglia, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.405912.
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Kwarkoh, Angela. "Conversion of Alcohols to Alkyl Azides Using O-Nitrobenzenesulfonyl Azide." Youngstown State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1380022166.
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Berndt, Christian. "Bildungstendenz und Reaktionen von α-Azidoalkoholen." Doctoral thesis, Universitätsbibliothek Chemnitz, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-112553.
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Gegenstand der vorliegenden Arbeit ist die Synthese von α-Azidoalkoholen durch die Reaktion von aliphatischen sowie aromatischen Aldehyden mit Stickstoffwasserstoffsäure. Dabei stellt sich ein Gleichgewicht ein, dessen Lage durch die Ermittlung der Gleichgewichtskonstanten quantitativ bestimmt wird. In jedem Fall besteht die Möglichkeit, den α-Azidoalkohol in der Gleichgewichtsmischung zu charakterisieren und teilweise gelingt die Isolierung der reinen α-Azidoalkohole bei tiefen Temperaturen sowie deren Charakterisierung mittels Tieftemperatur-NMR-Spektroskopie. Die Ausgangsaldehyde für die Synthese der α-Azidoalkohole besitzen elektronenschiebende oder elektronenziehende Substituenten oder sind prochiral oder besitzen funktionelle Gruppe für intramolekulare Reaktionen. Die Titelverbindungen werden mit Cyclooctin im Sinne einer 1,3-dipolaren Cycloaddition abgefangen oder mit Carbonsäurechloriden in die entsprechenden Ester der α-Azidoalkohole überführt. Das nur aus theoretischen Arbeiten bekannte Formylazid wird erstmals aus den α-Azidoalkoholen durch Oxidation hergestellt und in Lösung vollständig charakterisiert. Es werden zudem zahlreiche Alternativsynthesen für Formylazid erfolgreich durchgeführt.
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Feizy, Nilab [Verfasser], and Ulrich [Gutachter] Schatzschneider. "iClick-Reaktionen von Palladium(II)azid- und Platin(II)azid-Komplexen mit tridentaten N,N,N-Chelatliganden und elektronenarmen Alkinen / Nilab Feizy ; Gutachter: Ulrich Schatzschneider." Würzburg : Universität Würzburg, 2019. http://d-nb.info/1182902839/34.
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Hewlins, Stuart A. "Reactions of alkenes with nitrogen containing reagents." Thesis, University of Nottingham, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246192.
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Moghaddam, Alan. "A STUDY OF THE BEHAVIOR AND LOCALIZATION OF PT(II) AZIDE AND ALKYNE-MODIFIED DERIVATIVES IN CELLS USING BIOORTHOGONAL CHEMISTRY AND FLUORESCENCE MICROSCOPY." Thesis, University of Oregon, 2016. http://hdl.handle.net/1794/20727.
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Despite their ubiquitous use, Pt(II) anti-cancer drugs still suffer from many issues such as off-drug target effects, renal and nephrotoxicity as well as acquired and intrinsic drug resistance. To obtain a better understanding of how to mitigate these deleterious effects can be mitigated we first must know all the targets of these drugs. Highlighted in this dissertation is previous work performed by groups exploring the localization of Pt in cells using fluorescence microscopy. While Pt drugs such as cisplatin contain no native fluorescence, a great deal of work has been done to covalently modify complexes with fluorescent tags. From studies using this technique, it been reported that Pt can target a number of compartments within the cell ranging from the nucleus to the cytoplasm. With each different derivative being observed in varied cell lines it becomes difficult to deconvolute a universal pattern to where Pt localizes, furthermore, the connected fluorophore could also bias Pt localization.
To add general functionality and eliminate the bias of a pre-tethered fluorophore our lab has developed a number of different azide and alkyne-modified complexes that append a “reactive handle” to Pt compounds. This modification allows for use of the bioorthogonal azide-alkyne click reaction we are able to observe Pt localization after treatment. The focus of this work includes method development to conjugate a fluorophore to our Pt complexes in vitro and in cell cultures. We examined a number of different cell lines and observed frequent localization in the nucleolus of the cell. Also in this work is the development of methods to append multiple fluorophores to each Pt site to increase our ability to visualize these complexes in cells. Finally, we have also constructed a new Pt-azide that exhibits slower exchange kinetics due to a chelating exchangeable group. The use of this new complex will enable studies to determine whether changing the leaving group results in differential localization of Pt drugs in cells.
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Giovedi, Claudia. "Comportamento eletroquímico dos metais Co(II), Ni(II), Mn(II), Fe(II) e Zn(II) na presença do ligante azoteto." Universidade de São Paulo, 1998. http://www.teses.usp.br/teses/disponiveis/46/46133/tde-02122009-152133/.
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O comportamento eletroquímico dos metais cobalto(II), níquel(II), manganês(II), ferro(II) e zinco(II) na presença do ligante azoteto foi estudado em duas condições: variando-se a concentração do ligante em solução de 0 a 2,0 mol/L e apenas tendo-o pré-adsorvido na superficie do eletrodo de mercúrio, buscando-se assim esclarecer os fenômenos determinantes na extensão da atuação do ligante como mediador facilitando a etapa de transferência de elétrons do eletrodo para o metal. Os resultados obtidos nas duas séries de experimentos mostraram ser a extensão da atuação do ligante como mediador dependente do metal estudado. No primeiro caso a adição gradativa de azoteto às soluções que contêm os cátions metálicos causa a antecipação progressiva da onda de redução dos metais Co(II) e Ni(II), o deslocamento para potenciais progressivamente mais negativos no caso dos metais Mn(II) e Fe(II) e, para o Zn(II), uma pequena antecipação em baixas concentrações do ligante e em seguida o aumento de sobretensão. Tendo-se apenas o ligante adsorvido na superficie do eletrodo, verifica-se a diminuição da sobretensão de redução dos metais Co(II) e Ni(II), um pequeno aumento no caso do metal Zn(II) e a completa eliminação da reação de eletrodo para o Mn(II). As diferenças observadas nos dois experimentos, comprovaram a importância do fenômeno de complexação na superficie do eletrodo para que se verifique a atuação do ligante como mediador. No entanto, apesar da necessidade de ocorrer a interação do metal com o ligante para facilitar a reação de transferência de elétrons, o complexo formado na superficie do eletrodo não pode ser termodinamicamente mais estável que o aquo-íon do metal, pois neste caso ao invés da diminuição da sobretensão de redução do metal irá se registrar o deslocamento do potencial de redução diretamente para potenciais mais negativos.The electrochemical behaviour of cobalt(II), nickel(II), manganese(II), iron(II) and zinc(II) was studied in the presence of azide in two conditions: varying the ligand concentrations in solution from 0.0 to 2.0 mol/L and just pre-adsorbing it onto the mercury electrode surface, in order to evaluate the determining aspects on the extent of the action of the ligand as a mediator in facilitating electron transfer. The results obtained in the two sets of experiments showed to what extent the action of the ligand as a mediator is dependent on the metal studied. In the first case, the addition of azide to solutions of these metaIs causes the following: a progressive anticipation in the reduction waves of Co(lI) and Ni(II); the shift towards more negative potentials for Mn(II) and Fe(II); and for Zn(TT) a small shift towards more positive potentials at low azide concentrations followed by a shift towards more negative potentials. The experiments carried out with the pre-adsorption ofthe azide onto the mercury surface showed the shift of the reduction waves of Co(lI) and Ni(II) towards more positive potentials, a small shift towards more negative potentials for Zn(II) and the complete elimination of the electrode reaction for Mn(II). The differences observed in the two experiments proved the importance of the complexation phenomenon onto the electrode surface in order to occur the action of the ligand as a mediator. However, inspite of the need of the interaction between metal and ligand to facilitate the electron transfer, the complex formed onto the electrode surface cannot be thermodynamically more stable than its metal aquo-ion, as in this case it will be observed the shift of the reduction potential towards more negative potentials.
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Lopes, Luciana dos Santos. "EFEITO DE UMA AZIDA ORGÂNICA SOBRE A ATIVIDADE DA NTPDase EM LINFÓCITOS HUMANOS." Universidade Franciscana, 2009. http://tede.universidadefranciscana.edu.br:8080/handle/UFN-BDTD/237.
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Previous issue date: 2009-01-19Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The NTPDase (apirase-ect, ect-difosfoidrolase, CD39, EC 3.6.1.5) hydrolyses tri nucleotides and/or diphosphate. It is an ectonucleotidase, identified as the antigen surface of lymphoid cells, whose greatest expression leads to an increase in activity of ATPase and ADPase and these cells through the hydrolysis of ATP and ADP. The inhibitor of ecto-nucleotidases may represent valuable therapeutic tools to amplify the biological effects of extracellular nucleotides, since they induce apoptosis in lymphocytes, causing a state of immunosuppression. It is known through the literature that sodium azide produces a significant inhibition in the hydrolysis of ATP and ADP, caused this enzyme when it is used in concentrations around 20mM. The azides are chemical components widely used in organic synthesis, and remarkably stable in biological environment. The aim of this study was to determine the inhibitory effects of an organic azide derived from acetic acid in the hydrolysis of ATP and ADP, which is the activity of NTPDase of human lymphocytes. Since changes in distribution and activity of this enzyme have been reported in various pathological conditions, demonstrating its participation in the activation of lymphocyte, it is believed that the identification of new compounds inhibiting NTPDase will contribute to treatment of diseases where there is a need for immunosuppression, as allergies and autoimmune diseases. After incubation of lymphocytes in medium containing different concentrations of azide organic, there was a significant inhibition of ADP in the hydrolysis when used concentrations of 10 and 20 mM, and this of 50 and 77% respectively. Unverified inhibitory effects on the ATP hydrolysis with organic azide. A changed the hydrolysis of nucleotide adenine diphosphate, indicating that the substance could be used as an inhibitor of mixed NTPDase.
A NTPDase (ecto-apirase, ecto-difosfoidrolase, CD39, EC 3.6.1.5) hidrolisa nucleotídeos tri e/ou difosfatados. É uma ectonucleotidase, identificada como antígeno de superfície de células linfóides, cuja maior expressão leva a um aumento das atividades de ATPase e ADPase nestas células. Os inibidores de ecto-nucleotidases podem representar valiosas ferramentas terapêuticas para amplificar os efeitos biológicos dos nucleotídeos liberados no meio extracelular, uma vez que estes induzem apoptose nos linfócitos, causando um estado de imunodepressão. Sabe-se através da literatura que azida sódica, quando utilizada em concentrações em torno de 20mM, produz uma significativa inibição na hidrólise de ATP e ADP causada por esta enzima. As azidas são componentes químicos muito usados em sínteses orgânicas, sendo notavelmente estáveis em ambiente biológico. Este trabalho, procurou determinar os efeitos inibitórios de uma azida orgânica derivada do ácido acético na hidrólise de ATP e ADP, ou seja, na atividade da NTPDase de linfócitos humanos. Uma vez que alterações na atividade e distribuição desta enzima têm sido relatadas em várias condições patológicas, demonstrando sua participação na ativação do linfócito, acredita-se que a identificação de novos compostos inibidores da enzima NTPDase venha a contribuir em patologias onde há necessidade de uma imunossupressão, como em alergias e doenças autoimunes. Após incubação dos linfócitos em meio contendo diferentes concentrações de azida orgânica, verificou-se uma inibição significativa na hidrólise do ADP quando utilizadas as concentrações de 10 e 20 mM, sendo esta de 50 e 77%, respectivamente. Não foram verificados efeitos inibitórios sobre a hidrólise do ATP. A azida orgânica alterou a hidrólise dos nucleotídeos da adenina difosfatados, indicando que esta substância poderia ser utilizada como um inibidor da NTPDase, cujo tipo de inibição causada seria mista.
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Wen, Zhiwei. "Azido- and Triazolyl-modified Nucleoside/tide Analogues: Chemistry, Fluorescent Properties, and Anticancer Activities." FIU Digital Commons, 2018. https://digitalcommons.fiu.edu/etd/3789.
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Two classes of C5 azido-modified pyrimidine nucleosides were synthesized and explored as radiosensitizers. The 5-azidomethyl-2'-deoxyuridine (AmdU) was prepared from thymidine and converted to its cytosine counterpart (AmdC). The 5-(1-azidovinyl) modified 2'-deoxyuridine (AvdU) and 2'-deoxycytidine (AvdC) were prepared employing regioselective Ag-catalyzed hydroazidation of 5-ethynyl pyrimidine substrates with TMSN3. AmdU and AmdC were converted to 5'-triphosphates AmdUTP and AmdCTP, and incorporated into DNA-fragments via polymerase-catalyzed reaction during DNA replication and base excision repair. Radiation-mediated prehydrated electrons formed in homogeneous aqueous glassy (7.5 M LiCl) systems in the absence of oxygen at 77 K led to site-specific formation of π-type aminyl radicals (RNH•) from AmdU, AmdC, AvdU, and AvdC. The ESR spectral studies and DFT calculations showed RNH• undergo facile conversion to thermodynamically more stable σ-type iminyl radicals, R=N•. For AmdU, conversion of RNH• to R=N• was bimolecular involving α-azidoalkyl radical as intermediate; however, for AvdU, RNH• tautomerized to R=N•. Our work provides the first evidence for the formation of RNH• attached to C5 position of azidopyrimidine nucleoside and its facile conversion to R=N• under reductive environment. These aminyl and iminyl radicals can generate DNA damage via oxidative pathways. The azido-nucleosides were successfully applied as radiosensitizers in EMT6 cancer cells in both hypoxic and normoxic conditions. To explore the generation and reactivity of 2'‑deoxyguanosin-N2-yl radical (dG(N2-H)•) postulated to generate from guanine moiety towards •OH, 2-azido-2'-deoxyinosine (2-N3dI) was prepared by conversion of 2-amino group in protected dG into 2-azido via diazotization with tert-butyl nitrite followed by displacement with azide and deprotection. The investigation of dG(N2-H)• generated from 2-N3dI and its subsequent reactions using ESR will be discussed.
Cycloaddition between 5-ethynylpyrimidine or 8-ethynylpurine nucleosides and TMSN3 in the presence of Ag2CO3, CuI, or CuSO4/sodium ascorbate provided N-unsubstituted 1,2,3-triazol-4-yl analogues of the parental DNA bases (i.e. 5-TrzdU, 5‑TrzdC, 8-TrzdA, and 8-TrzdG). These novel triazolyl nucleosides showed excellent fluorescent properties: 8-TrzdA exhibits the highest quantum yield (ΦF) of 44% while 8‑TrzdG had ΦF of 9%. The 5-TrzdU and 5-TrzdC showed a large Stokes shift of ~110 nm. The application of these fluorescent nucleosides to cell imaging and DNA modifications will also be discussed.
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Conway, Louis Patrick. "The aqueous phosphorylation and ligation of nucleoside analogues and aqueous azide reduction methodology." Thesis, Durham University, 2014. http://etheses.dur.ac.uk/10735/.
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The research within this thesis is primarily concerned with the synthesis of modified nucleosides, their oxyphosphorylation and thiophosphorylation to form analogues of nucleoside monophosphates and phosphodiester linkages, and the chemistry of the thiophosphoryl group. These families of compounds may have potential in the areas of antisense oligonucleotide agents or nuclease inhibition. The work described here may also provide routes to new glycosyltransferase inhibitors. This work builds upon previous work in the Hodgson research group, principally the thiophosphorylation and subsequent alkylation of organic amine fragments as a ligation strategy, and the optimisation of the thiophosphorylation procedure as applied to 5$'$\hyp{}amino\hyp{}5$'$\hyp{}deoxyguanosine. My role was to extend these techniques to the thiophosphorylation of other nucleoside derivatives and to use the thiophosphorylation procedure to produce potentially biologically active compounds. This thesis is divided into a number of chapters and appendices, and commences by providing a review of the synthesis, properties, and applications of natural and unnatural phosphodiester compounds in the first chapter. The second chapter details the work which has already been carried out within this research group on the synthesis, oxyphosphorylation, and thiophosphorylation of aminodeoxynucleosides; this forms the foundation to my own work on optimisation of the oxyphosphorylation procedure, and the application of both the oxyphosphorylation and the thiophosphorylation methodology to other aminodeoxynucleosides. The third chapter describes the application of the thiophosphorylation procedure to the synthesis of a thiophosphoramidate mimic of a dinucleoside. The following chapter concerns the investigations into the hydrolytic stability of the thiophosphoramidate group, using the dinucleoside thiophosphoramidate analogue as a model. The fifth chapter is on an aqueous method for the reduction of organic azides using the thiophosphate ion as the reducing agent. The reaction was tested on a number of alkyl and aryl susbstrates, and the mechanism of the reduction was investigated. Appended to this thesis are some chapters on work related to the main project in their application of modified nucleosides and nucleotides; in the first appendix, modifications were made to the phosphate group of guanosine monophosphate to allow the role of the phosphate group in the formation of G-quadruplex structures to be studied. The second appendix concerns work done in support of a project to incorporate 5$'$-deoxy-5$'$-hydrazinoguanosine into the 5$'$- terminus of RNA strands, which allowed the termini to be labelled with fluorescein isothiocyanate (FITC). Using 5$'$-deoxy-5$'$-hydrazinoguanosine as a model for the modified RNA strands, it was shown that within the limits of detection, each hydrazine group reacts with only one molecule of FITC.
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AGUIRRE, DE PAZ JOSE GUADALUPE 701370, and DE PAZ JOSE GUADALUPE AGUIRRE. "Síntesis de nuevos análogos de la Rufinamida vía cicloadiciones [3+2] azida–enolato." Tesis de maestría, Universidad Autónoma del Estado de México, 2018. http://hdl.handle.net/20.500.11799/71092.
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Tesis de MaestríaRecientemente, la FDA aprobó el uso de la Rufinamida como nuevo fármaco antiepiléptico, primer y único derivado triazólico para este tratamiento médico. Ya que éste es un fármaco relativamente nuevo, se entiende que la química (síntesis) y biología (farmacología-farmacovigilancia) de este compuesto se encuentra actualmente en sus inicios. Con el fin de incursionar en el entendimiento de la química de dicho compuesto, se llevó a cabo la obtención de análogos de la Rufinamida, aplicando como estrategia sintética la cicloadición [3+2] azida–enolato, metodología recientemente publicada por Carlos González
CONACYT, Secretaría de Investigación y Estudios Avanzados de la Universidad Autónoma del Estado de México.
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Fuchs, Pascal [Verfasser]. "Kupfer-katalysierte Azid-Alkin-Cycloaddition zur Modifikation von Kohlenhydraten / Pascal Fuchs." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2020. http://d-nb.info/1216703671/34.
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