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Design And Synthesis Of Potential Tlr7 And Tlr8 Inhibitors, Patrick Nordeen 2018 University of Colorado at Boulder

Design And Synthesis Of Potential Tlr7 And Tlr8 Inhibitors, Patrick Nordeen

Chemistry & Biochemistry Graduate Theses & Dissertations (1986-2018)

Toll-like receptors (TLRs) detect invading viral and bacterial pathogens and play a critical role in the initiation and regulation of the innate immune system. Over-active TLR signaling has been indicated in the disease pathology of numerous crippling inflammatory autoimmune disorders and inhibition of these receptors is of considerable interest for therapeutic intervention. TLR7 and TLR8 are the two TLRs that share the most similarity in both sequence and structure. Despite their similarity, selective inhibition represents a promising therapy for diseases such as systemic lupus erythematosus (lupus) and rheumatoid arthritis (RA). The goal of this master’s thesis is to identify ...


Synthesis Of The Key Fragments Of Micrococcin P1 And Thiocillin I, Aaron Bret Hinds 2018 University of Colorado at Boulder

Synthesis Of The Key Fragments Of Micrococcin P1 And Thiocillin I, Aaron Bret Hinds

Chemistry & Biochemistry Graduate Theses & Dissertations (1986-2018)

Thiopeptide antibiotics are members of the ribosomally synthesized and post-translationally modified peptide class of natural products. They contain a unique trisubstituted six-membered nitrogen ring decorated with azol(in)e heterocycles, dehydroamino acids, and a macrocyclic structure. Thiopeptides act by inhibiting the bacterial ribosome and have demonstrated potent activities against a wide range of Gram-positive pathogens.

This work describes the synthesis of the two key fragments used in our total syntheses of micrococcin P1 and thiocillin I. The “bottom” fragments were assembled through modification and coupling of amino acids as well as the use of a molybdenum catalyzed cyclodehydration of cysteine ...


Development Of A Modular Synthesis Of Rigid Polyacene Dimers For Mechanistic Exploration Of Singlet Fission, Thomas James Carey 2018 University of Colorado at Boulder

Development Of A Modular Synthesis Of Rigid Polyacene Dimers For Mechanistic Exploration Of Singlet Fission, Thomas James Carey

Chemistry & Biochemistry Graduate Theses & Dissertations (1986-2018)

Singlet Fission (SF) is a non-radiative, spin-allowed, photophysical process wherein a singlet excited state converts into a pair of spin-coupled triplet states. This process has implications for improving solar cell efficiency, as SF offers a way to process high energy photons by proportionating their energy into pairs of electronic excitations rather than wasting excess energy as heat. Of particular interest has been the study of molecular dimers, as these are the simplest systems capable of SF and offer a platform for understanding mechanistic details for the development of efficient SF systems.

This dissertation describes the development of a modular synthesis ...


Synthesis And Biochemical Evaluation Of Aminoboranephosphonate Phosphoramidimidate And Phosphoramidate Dna, Ayman Ghalib Alawneh 2018 University of Colorado at Boulder

Synthesis And Biochemical Evaluation Of Aminoboranephosphonate Phosphoramidimidate And Phosphoramidate Dna, Ayman Ghalib Alawneh

Chemistry & Biochemistry Graduate Theses & Dissertations (1986-2018)

Antisense oligonucleotides are synthetic DNAs that bind to RNA and alter or reduce the biological activity of the target RNA. Studies performed in recent years have demonstrated that an antisense strategy can be utilized to address various issues in fundamental biomedical research and have additionally shown that this approach can be used to create novel therapeutic drugs. For example, IONIS Pharmaceuticals has so far commercialized three drugs using antisense oligonucleotides. These drugs target spinal muscular atrophy, homozygous familial hypercholesterolemia, and pouchitis. Antisense oligonucleotides targeting several other diseases are in various stages of clinical study at IONIS and elsewhere.

My research ...


The Preparation Of Palladium Complexes Of N-Pyrazolylpropanamide Derivatives, Tyler Palombo 5275714 2018 James Madison University

The Preparation Of Palladium Complexes Of N-Pyrazolylpropanamide Derivatives, Tyler Palombo 5275714

Senior Honors Projects, 2010-current

The reaction of 3,5-dimethylpyrazolyl-N-isopropylpropanamide (L1) with dichloro(1,5-cyclooctadiene)palladium(II) displaces cyclooctadiene forming Cl2Pd(L1)2. This complex has been characterized by NMR and IR spectroscopy, single crystal X-Ray diffraction, and elemental analysis. It is composed of a square planar Pd with trans L1 ligands attached through a pyrazolyl nitrogen and intramolecular hydrogen bonding between the amide and chloride. Similar reactions were carried out with 3,5-dimethylpyrazolylpropanamide (L2), pyrazolyl-N-isopropylpropanamide (L3), 3-(1H-benzotriazol-1-yl)-N,N-dimethylpropanamide (L4), 3-methylpyrazolylpropanamide (L5), 3-(1H-benzotriazol-1-yl)-2-methylpropanamide (L6), and N-pyrazolypropanamide (L7) presumably forming analogous complexes. This formulation for Cl2Pd(L2)2 ...


Mechanistic Investigations Of The Iron(Iii)-Catalyzed Carbonyl-Olefin Metathesis Reaction, Susan Phan 2018 Loyola University Chicago

Mechanistic Investigations Of The Iron(Iii)-Catalyzed Carbonyl-Olefin Metathesis Reaction, Susan Phan

Master's Theses

Iron(III)-catalyzed carbonyl-olefin ring-closing metathesis represents a new approach toward the assembly of molecules traditionally generated by olefinˆ’olefin metathesis or olefination. Herein, we report detailed synthetic, spectroscopic, kinetic, and computational studies to determine the mechanistic features imparted by iron(III), substrate, and temperature to the catalytic cycle. These data are consistent with an iron(III)-mediated asynchronous, concerted [2+2]-cycloaddition to form an intermediate oxetane as the turnover-limiting step. Fragmentation of the oxetane via Lewis acid-activation results in the formation of five- and six-membered unsaturated carbocycles.


The Enzymatic Activity And Inhibition Of Dape Encoded N-Succinyl-L,L-Diaminopimelic Acid Dessucinylase, Tahirah Heath 2018 Loyola University Chicago

The Enzymatic Activity And Inhibition Of Dape Encoded N-Succinyl-L,L-Diaminopimelic Acid Dessucinylase, Tahirah Heath

Dissertations

The bacterial enzyme DapE is a hydrolase in the late stage of the mDAP/lysine biosynthetic pathway that catalyzes the hydrolysis of N-succinyl-L,L-diaminopimelic acid (L,L-SDAP) to succinic acid and L,L-diaminopimelate (DAP). The product DAP is ultimately converted to m-DAP and then to lysine which is used in the construction of proteins, whereas for humans, lysine is an essential amino acid obtained through diet. DapE has been shown to be conserved across many strains of bacteria. The m-DAP produced through the succinylase pathway is used by both gram negative and gram-positive bacteria in the construction of the essential ...


Investigation Of The Exraction Processes And Performance Properties Of Kudzu Fibers, Bahrum Prang Rocky, Virginia Wimberley 2018 University of Alabama

Investigation Of The Exraction Processes And Performance Properties Of Kudzu Fibers, Bahrum Prang Rocky, Virginia Wimberley

International Textile and Apparel Association (ITAA) Annual Conference Proceedings

While kudzu was introduced into the Southeastern United states for soil erosion and increase of land fertility, the plant has become unmanageable and is rapidly spreading to Canada. Japanese traditional craftsmen extract long, white fibers by labor intensive practices not feasible for 21st century commercial fiber production. This research investigated extraction by boiling, retting or fermentation, enzymatic combinations, and mild chemical processes. Two types of fibers were resultant- soft fibers and compact woody fibers. These fibers types were assessed for microscopic visual appearance, elemental analysis using EDAX SEM, and tensile strengths for the four extraction processes. In all extraction cases ...


Molecular Level Encapsulation Of Chromophores Using Pillar[5]Arenes For Enhanced Photostability, Manik Gudimani 2018 South Dakota State University

Molecular Level Encapsulation Of Chromophores Using Pillar[5]Arenes For Enhanced Photostability, Manik Gudimani

Electronic Theses and Dissertations

Organic π-conjugated materials have been researched extensively for a number of applications including organic photovoltaics, electrooptic (EO) modulation, solid-state lasing, organic light emitting diodes (OLEDs), biological imaging and sensing, chemical sensing and ligands for photocatalysts. These organic optoelectronic materials have one major issue that affects its performance and lifetime—photostability. For some applications, hermetical packaging, which is expensive, is required to prevent degradation by light and oxygen. Photooxidation occurs when a material is exposed to light and causes structural and chemical changes leading to photodegradation of the material. The two primary degradation mechanisms responsible for photooxidation involve superoxide radical anion ...


Investigating Degradation Pathways In Organic Solar Cell Materials, Satvik Shah 2018 Iowa State University

Investigating Degradation Pathways In Organic Solar Cell Materials, Satvik Shah

Graduate Theses and Dissertations

Thin film organic solar is a recent technology with tremendous potential – low cost materials, quicker manufacturing processes and synthetic tuning of organic materials to optimize material properties. Cell efficiencies > 12% have already been achieved. But the bottleneck problem this technology faces is instability. Performance of these cells degrades much faster than traditional solar cells. The degradation occurs on exposure to solar radiation, both through extrinsic ingress of moisture and oxygen as well as intrinsic degradation mechanisms.

One of the most common type of thin film organic cell with efficiency ~10% is PTB7:PCBM organic solar cell. Hence I have tried ...


Design And Application Of Porous Organic Frameworks For Recyclable, Heterogeneous, Transition-Metal Catalysis, Brian Schumacher 2018 Iowa State University

Design And Application Of Porous Organic Frameworks For Recyclable, Heterogeneous, Transition-Metal Catalysis, Brian Schumacher

Graduate Theses and Dissertations

In this thesis, heterogeneous frameworks are explored and examined for their use in recyclable catalysis. Specifically, metal-organic-frameworks (MOFs) and covalent-organic-frameworks (COFs) containing bidentate nitrogen ligands are pursued for their use in transition metal catalysis.

Palladium(II)-functionalized COF (Pd@TpBpy COF) is demonstrated as a recyclable, heterogeneous catalyst for palladium-catalyzed conjugate addition of arylboronic acids to β,β-disubstituted enones to form ketone products containing all-carbon quaternary centers in aqueous 50 mM NaTFA as the reaction medium. A wide range of arylboronic acids are added to various β,β-disubstituted enones in moderate-to-high yields.

Pyridine oxazoline derivatives are designed and synthesized for ...


Intramolecularly Enhanced Receptors With Unusual Binding And Molecularly Imprinted Nanoparticles As Nanoreactors And Sensors, Xiaoyu Xing 2018 Iowa State University

Intramolecularly Enhanced Receptors With Unusual Binding And Molecularly Imprinted Nanoparticles As Nanoreactors And Sensors, Xiaoyu Xing

Graduate Theses and Dissertations

The conformational flexibility of a receptor is usually considered unfavorable to binding, due to the entropy loss upon binding. Inspired by the biological receptor with intra-receptor secondary binding sites which can strengthen guest binding, two series of artificial receptors with similar structures were constructed: pseudo crown ethers with aromatic donor/acceptor groups and aromatic tweezer molecules with carboxylic acids. When the guest binding was weakened by the solvents, i.e., pseudo crown ethers bound with cations in polar solvents and aromatic tweezers bound with counterparts in non-polar solvents, intra-receptor interactions became stronger and contributed to the guest binding. The overall ...


Manipulating Push-Pull Systems To Probe Biology And Photochemistry, Andrea Thooft 2018 Iowa State University

Manipulating Push-Pull Systems To Probe Biology And Photochemistry, Andrea Thooft

Graduate Theses and Dissertations

Photochemistry and photophysics are two rapidly expanding areas in science. The first part of this dissertation looks at the synthesis of a new fluorescent probe based on the well-known fluorophore nitrobenzoxadiazole (NBD). We synthesized a new derivative using the nitrile functional group as the electron withdrawing group. Our results showed our fluorophore (CBD) displayed redder emission than the nitro counterpart, and an emission range that was similar to that of the sulfonamide containing derivatives. Additionally CBD displayed extensive solvatochromic properties: high quantum yield and bluer emissions in nonpolar solvents while low quantum yield and redder emissions as the solvent polarity ...


Brønsted Acid Catalyzed Carbon-Carbon Bond Forming Reactions, Jiangyue Miao 2018 University of Denver

Brønsted Acid Catalyzed Carbon-Carbon Bond Forming Reactions, Jiangyue Miao

Electronic Theses and Dissertations

The focus of this research project lies in the development of new methodology in the field of Brønsted acid catalysis enabling rapid synthesis of medicinally relevant compounds. It is foreseen that small molecule sulfonic acids evaluated in this research project will unveil new asymmetric carbon carbon bond forming reactions between substrates hitherto unexplored with Brønsted acid catalysis. It has been established that strong Brønsted acids, such as phosphoric acids, are capable of mediating highly selective transformations operating through unique mechanistic manifolds.

Specific focus for the sulfonic acid catalysts was geared towards asymmetric coupling reactions with synthetically useful precursors such as ...


Formulation And Characterization Of Lipogels As A Tunable Delivery Scaffold, Celia Homyak 2018 University of Massachusetts Amherst

Formulation And Characterization Of Lipogels As A Tunable Delivery Scaffold, Celia Homyak

Doctoral Dissertations

Nanomedicines within the clinic commonly utilize lipid-based scaffolds due to their aqueous assembly and non-covalent dual-guest loading capabilities. Nevertheless, poor stability in vivo and premature guest release remains a challenge with these systems. Polymeric nanomaterials are a popular alternative due to their good stability in vivo with controllable guest release. A caveat to polymeric scaffolds though, is the excess synthetic effort involved for non-covalent dual-drug encapsulation. Benefit lies in harnessing advantages of lipid and polymeric materials via lipid-polymer hybrid scaffold. Such materials have promise due to their dual-encapsulation and dual-stimuli-sensitive characteristics. The need to better understand these materials led us ...


Light-Harvesting And Light-Responsive Materials For Optoelectronic And Biological Applications, youngju bae 2018 University of Massachusetts Amherst

Light-Harvesting And Light-Responsive Materials For Optoelectronic And Biological Applications, Youngju Bae

Doctoral Dissertations

In photodynamic therapy, several critical standards are required of photosensitizers including high singlet oxygen quantum yield, biocompatibility in dark, and long term photochemical stability. In addition, current PDT systems lack active targeting strategies to tumor cells, and instead mainly rely on the natural distribution of PS in the body following injection and application of near-infrared light treatment in the tumor region. This thesis describes a series of BODIPY-based molecules that were designed, synthesized and studied as photosensitizers with high singlet oxygen generation capacity through utilizing the heavy atom effect. Additionally, aqueous solubility and active targeting capability were introduced by photosensitizer ...


Design And Synthesis Of Stimuli-Responsive Polymeric Nanogels Towards Therapeutic Translation, Mallory R. Gordon 2018 University of Massachusetts Amherst

Design And Synthesis Of Stimuli-Responsive Polymeric Nanogels Towards Therapeutic Translation, Mallory R. Gordon

Doctoral Dissertations

In the application of delivery of therapeutics, nanostructures of various composition have been employed due to their capacity to act as a host for lipophilic payloads. Advances in the synthetic preparation, size, morphology, and chemical or physical characteristics of polymers have impacted their development and versatility. A detailed understanding of polymeric nanoparticle host-guest properties is crucial to their practical translation to specific delivery applications. Further, these features must be highly tailorable to overcome biological barriers, stably encapsulate their therapeutic contexts, and exhibit payload release selectively in the target environment. In this dissertation, we aim to rationally design polymeric nano-scale assemblies ...


Synthesis Of Asymmetrically Substituted Scyllo-Inositol, Jacob Rodriguez 2018 University of Colorado, Boulder

Synthesis Of Asymmetrically Substituted Scyllo-Inositol, Jacob Rodriguez

Undergraduate Honors Theses

This work describes the total synthesis and characterization of an asymmetrically substituted scyllo-inositol. Starting from a cheap an abundant α-D-methylglucoside, generation of the product was achieved in nine steps. This synthesis capitalized on a Ferrier II reaction which generated the inositol core, followed by a selective reduction, protection, and stereochemical inversion to convert the initial myo-inositol to the desired scyllo-inositol. This asymmetric scyllo-inositol will be used in the future as the head of axinelloside A.


Cellulose Modification For Use As Reinforcement In Bio-Based Composites, Ashley L. Rudolph 2018 Georgia Southern University

Cellulose Modification For Use As Reinforcement In Bio-Based Composites, Ashley L. Rudolph

Electronic Theses and Dissertations

The goal of the research contained in this thesis is to provide an alternative method of developing polymers than the current petroleum-based polymeric products. Vegetable oil-based polymers are a popular alternative due to their low-cost and low toxicity. The carbon-carbon double bonds in the oil are ideal reactive sites for a free radical polymerization. Cellulose is a naturally occurring polymer. Modifying cellulose prior to making composites with tung oil allows a hydrophilic material to mix better with a hydrophobic resin. Vegetable oil-based polymers usually require the reinforcement of fibers to enhance the thermo-mechanical properties that would replace petroleum-based polymers. In ...


Synthesis And Catalytic Testing Of A Proline Functionalized Amphiphilic Block Copolymer, Eric Firestone 2018 Eastern Michigan University

Synthesis And Catalytic Testing Of A Proline Functionalized Amphiphilic Block Copolymer, Eric Firestone

Master's Theses and Doctoral Dissertations

Catalysts are reagents used to reduce the amount of energy that a reaction needs to execute, allowing it to proceed at a higher rate while not being consumed. The use of catalyst functionalized amphiphilic copolymer allows easier recovery of the catalyst at the end of the synthesis and allows for the reaction. In water, under appropriate conditions, the amphiphilic block copolymers will form micelles and allow the reaction to occur on the interior of the micelle. The synthesis of amphiphilic copolymer with a hydrophobic O-methacryloyl-trans-4- hydroxy-L-proline and methyl methacrylate end and a hydrophilic acrylic acid end was characterized. The polymer ...


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