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Strain Promoted Click Chemistry of 8-Azidopurine and 5-Azidopyrimidine Nucleosides and Nucleotides with Cyclooctynes and Applications to Living Cell ImagingZayas, Jessica 10 June 2015 (has links)
The strain promoted azide alkyne cycloaddition (SPAAC) of azido nucleobase modified nucleosides and nucleotides with cyclooctynes to give fluorescent triazoles has been relatively unexplored. Thus, SPAAC between azido-nucleobases and various cyclooctynes in aqueous solution at ambient temperature resulted in the efficient formation (3 min - 2 h) of triazole products with inherent fluorescent properties. The 2- and 8-azidoadenine nucleosides reacted with fused cyclopropyl cyclooctyne, dibenzylcyclooctyne or monofluorocyclooctyne to produce click products functionalized with hydroxyl, amino, N-hydroxysuccinimide, or biotin moieties. The previously unexplored 5-azidouridine and labile 5-azido-2'-deoxyuridine were similarly converted to the analogous triazole products in quantitative yields in less than 5 minutes. The 8-azido-ATP quantitatively afforded the triazole product with fused cyclopropyl cyclooctyne (3 h). Addition of a triazole ring at the 2 or 8 position of adenine or 5-position of uracil induces fluorescent properties which were used for direct imaging with fluorescent microscopy in MCF-7 cancer cells without the need for traditional fluorogenic reporters. Fluorescent lifetime imaging microscopy of the click adducts in live cells were used to determine the lifetime of each fluorophore in the cellular nuclei demonstrating the potential utility of the synthesized triazole adducts for dynamic measuring and tracking of events inside single living cancer cells.
The SPAAC methodology developed has also been applied to study the cellular targets in protozoal parasite, Trichomonas vaginalis and bacteria, Pseudomonas aeruginosa. The 9-(2-deoxy-2-fluoro-β,D-arabino-furanosyl)adenine (arabino-F-Ado) was modified with an azido moiety at the C8 position for use in click chemistry. Tagging and subcellular localization studies using azido modified arabino-F-Ado could provide insight into the mechanism of action of arabino-F-Ado.
An activated analogue of S-adenosyl-L-methionine (SAM) with an EnYn group on the sulfur instead of a methyl group was prepared to study the transfer of the methyl group from SAM. I found that the EnYn group was transferred from SAM to a guanosine on tRNA by methytransferase Trm1. Thus, AdoEnYn is a competitive inhibitor of SAM and can be incorporated into tRNA in place of SAM.
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Click Chemistry Approach to Analyze Curcumin-Protein Interactions in vitro and in vivoZhou, Jingyi 20 August 2019 (has links)
Over the past decades, numerous studies shown curcumin, a dietary compound derived from turmeric, has a variety of health-promoting actions, such as anti-oxidant, anti-microbial, anti-inflammatory, and anti-cancer effects, making curcumin the most promising dietary compound for disease prevention. However, the underlying mechanisms by which curcumin has these health-promoting effects are not well understood. A better understanding of the molecular mechanism of curcumin could help to develop novel strategies to reduce the risks of some human diseases.
Protein thiols play important roles in cell signaling, and recent studies showed that curcumin could covalently react with protein thiols, supporting that curcumin-protein interactions could contribute to the health-promoting effects of curcumin. However, the curcumin-protein interactions are under-studied. Notably, it remains unknown whether oral intake of curcumin could covalently interact with protein in vivo. In this project, we synthesized a click chemistry probe of curcumin (Di-Cur), and used this probe to characterize curcumin-protein interactions both in vitro and in vivo using a click chemistry-based imaging approach. Our results demonstrate that orally administrated curcumin could form curcumin-protein adducts in specific tissues of the mice, which may contribute to the potent biological effects and poor pharmacokinetics of curcumin.
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Cancer drugs targeting DNA replication: Molecular strategies to enhance specificity and efficacyLi, Yizhu 06 July 2021 (has links)
No description available.
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The Synthesis and Modification of Nanosized Clickable Latex ParticlesAlmahdali, Sarah 05 1900 (has links)
This research aims to add to the current knowledge available for miniemulsion polymerization reactions and to use this knowledge to synthesize multifunctional nanosized latex particles that have the potential to be used in catalysis. The physical properties of the latex can be adjusted to suit various environments due to the multiple functional groups present. For this research, styrene, pentafluorostyrene, azidomethyl styrene, pentafluorostyrene with azidomethyl styrene and pentafluorostyrene with styrene latexes were produced, and analyzed by dynamic light scattering. The latexes were synthesized using a miniemulsion polymerization technique found through this research. Potassium oleate and potassium 1,1,2,2,3,3,4,4-nonafluorobutane-1-sulfonate were used as surfactants during the miniemulsion polymerization reaction to synthesize pentafluorostyrene with azidomethyl styrene latex. Transmission electron microscopy data and dynamic light scattering data have been collected to analyze the structure of this latex, and it has been synthesized using a number of conditions, differing in reaction time, surfactant amount and sonication methods. We have also improved the solubility of the latex through a copper(I) catalyzed 1,3-dipolar azide-alkyne reaction, by clicking (polyethylene glycol)5000 onto the azide functional groups.
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STUDY OF CLICK CHEMISTRY: WORKING TOWARDS ‘CLICKING’ A NON-STEROIDAL ANTI-INFLAMMATORY TO AN APOPTOSIS INHIBITOR Q-VD-OPHTesak, Jennifer Lynn January 2012 (has links)
No description available.
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Construction of the Novel Core/interfacial Crosslinked Inorganic/organic Hybrid Micelle Based on Functionalized Polyhedral Oligomeric Silsesquioxane (POSS) via Thiol-ene "Click" ChemistryChen, Ziran 06 June 2013 (has links)
No description available.
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The First Attachment and Post-Functionalization of Polybutadiene and Thio-Click Functionalized Polybutadiene on H-Terminated Si(111)Wickard, Todd DeVere 20 March 2009 (has links) (PDF)
I report the attachment of polymers with pendant vinyl groups to hydrogen-terminated silicon(111) (Si(111)-H) under mild conditions. 1,2-addition polybutadiene (Mw 3200-3500) was attached to Si(111)-H at room temperature with visible light. I also report the partial functionalization, in solution, of 1,2-addition polybutadiene with various thiols using thiol-click chemistry. These compounds bind to Si(111)-H via visible light activation. The partially functionalized polybutadienes allow further functionalization at the surface through unreacted carbon-carbon double bonds. Surfaces were characterized with contact angle goniometry, spectroscopic ellipsometry, X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry (ToF-SIMS), and atomic force microscopy (AFM).
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Macromolecular Structure Evolution of Giant Molecules Via "Click" Chemistry: Asymmetric Giant Gemini Surfactants Based on Polyhedral Oligomeric SilsesquioxaneSu, Hao 09 June 2014 (has links)
No description available.
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Click Chemistry Synthesis of Neoglycooligomers and NeoglycopolymersMills, Isaac N. 28 September 2012 (has links)
No description available.
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Fluor-labeling of RNA and Fluorescence-based Studies of Precursor-tRNA Cleavage by Escherichia coli Ribonuclease PWallace, Andrew J. 24 October 2013 (has links)
No description available.
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