Conformational Modulation Of Α-Helical N-Acetylated Α-Synuclein,
2021
Virginia Commonwealth University
Conformational Modulation Of Α-Helical N-Acetylated Α-Synuclein, Ricardo Fernandez
Theses and Dissertations
Human N-acetylated α-synuclein (NAcαSyn) has long been accepted as an intrinsically disordered protein (IDP) predominantly found in terminal nerve regions in healthy subjects. NAcαSyn structural fluidity enables the formation of transient or dynamic assemblies. Some of these assemblies may serve functional, yet undefined purposes. NAcαSyn is highly susceptible to the surrounding environment, leading to misfolding under high cytosolic oxidative stress conditions, which in turn assemble in the form of toxic oligomers or amyloid fibrils. These NAcαSyn inclusions along with their accretion and migration within neurons, are pathological hallmarks of Parkinson’s disease (PD), dementia, and multiple …
Streptococcus Sanguinis: The Good, The Bad, And The Metal-Binding Lipoprotein,
2021
Virginia Commonwealth University
Streptococcus Sanguinis: The Good, The Bad, And The Metal-Binding Lipoprotein, Cody Murgas
Theses and Dissertations
Streptococcus sanguinis is an opportunistic bacterium living beneficially in the human mouth. When S. sanguinis gains access to the bloodstream, it can result in colonization on damaged tissue and generate heart valve vegetations that can develop into infective endocarditis. It has been suggested that Mn and Fe are cofactors in the pathogenic capacity of this bacterium, and that these redox active metals are imported by the metal binding lipoprotein S. sanguinis adhesin B (SsaB). The SsaB lipoprotein is an integral part of SsaACB, an ATP-binding cassette (ABC) transport system in S. sanguinis. When SsaB is deleted, the resulting strain displays …
Design, Synthesis, And Anticancer Properties Of Ru(Ii) Complexes With Organometallic, “Expanded” Bipyridine, And O,O’-Chelating Ligands,
2021
University of Kentucky
Design, Synthesis, And Anticancer Properties Of Ru(Ii) Complexes With Organometallic, “Expanded” Bipyridine, And O,O’-Chelating Ligands, Raphael Ryan
Theses and Dissertations--Chemistry
Cancer is a worldwide public health crisis that requires new and improved drugs to be developed to extend survival rates and improve quality of life for the patient. Platinum-based drugs are used in approximately 50% of cancer treatment regimens. These drugs are highly effective in many kinds of cancer; however, cancers can develop platinum resistance and these drugs have troubling side effects that reduced their use and efficacy. To overcome these disadvantages, many other metals have been studied for their anticancer properties. Notably, the anticancer properties of ruthenium-based agents have drawn considerable attention with multiple ruthenium complexes entering clinical trials. …
Metal Complexes Of Bis(Pyrazolyl)Methane-Based Ditopic Ligands,
2021
Eastern Illinois University
Metal Complexes Of Bis(Pyrazolyl)Methane-Based Ditopic Ligands, Pubudu Nuwan Perera Hapuarachchige
Masters Theses
No abstract provided.
Developing Synthetic Strategies For Multifaceted Applications Of Stable Gold-Based Complexes,
2021
University of Kentucky
Developing Synthetic Strategies For Multifaceted Applications Of Stable Gold-Based Complexes, Randall Tyler Mertens
Theses and Dissertations--Chemistry
Development of stable gold-based complexes has been a rapidly advancing field due to the popularity of gold complexes, particularly for use in biomedical research and catalytic transformations. Given that auranofin, a gold(I) complex with FDA approval for the treatment of rheumatoid arthritis is used in the clinic, the development of stable gold-based molecules of clinical relevance is urgently needed. Herein are reported, synthetic strategies used for the development of new classes of gold(I) and gold(III) complexes for advancement in mitochondrial modulation for use as chemotherapeutics as well as application to gold catalysis due to the unique geometry of complexes presented …
Generation, Characterization, And C-H Bond Activation Reactivity By Mononuclear High-Valent Cobalt(Iv) And Nickel(Iv) Non-Oxo Complexes,
2021
University of Montana
Generation, Characterization, And C-H Bond Activation Reactivity By Mononuclear High-Valent Cobalt(Iv) And Nickel(Iv) Non-Oxo Complexes, Yubin Maria Kwon
Graduate Student Theses, Dissertations, & Professional Papers
The study of terminal high-valent transition metal-oxo complexes has increased significantly over the years as it is believed that they are key reactive intermediates for a wide range of biological and industrial catalytic processes. These complexes are powerful oxidants for the activation of strong C-H bonds. The chemical and physical properties of these complexes remain elusive. It is therefore desirable to study the properties and function of these complexes through synthetic models. There have been many efforts and reports of synthetic high-valent metal-oxo complexes of early and middle transition metals (up to group 8 on the Periodic Table of Elements), …
Synthesis And Characterization Of Redox Non-Innocent Ligand Supported Transition Metal Complexes,
2021
Loyola University Chicago
Synthesis And Characterization Of Redox Non-Innocent Ligand Supported Transition Metal Complexes, Adriana Marie Lugosan
Dissertations
Catalysis is an integral part of society, which is often taken for granted. Over the past few years, there has been an increased effort to develop catalysts that are more environmentally friendly, selective, and energy efficient. This work focuses on the development of novel complexes made from a carefully designed non-innocent ligand together with earth-abundant and cost-effective transition metals that can be used to understand fundamental inorganic chemistry principles and serve as model systems. The work reported within validates the utility of this novel class of redox non-innocent ligand to form metal complexes with interesting properties, such as a non-porphyrin …
The Rational Synthesis Of Lanthanum Manganite Nanomaterials For Magnetic Refrigeration Applications,
2021
Virginia Commonwealth University
The Rational Synthesis Of Lanthanum Manganite Nanomaterials For Magnetic Refrigeration Applications, Caitlin Hunt
Theses and Dissertations
Refrigeration systems for the cooling of commercial and residential buildings are a major drain on energy resources and source of greenhouse gas emissions. Magnetic refrigeration, which employs the magnetocaloric effect, has the potential to mitigate the energy drain and greenhouse gas emissions for air conditioning. In order to commercialize magnetic refrigerators, a material with a high magnetic entropy change, ΔS, near room temperature which is simple and inexpensive to create is needed.1 Current options for this solid refrigerant are either expensive, difficult to synthesize, or have a ΔS or Tc (the Curie Temperature, where ΔS is maximized) below …
Accurate Quantitation Of Hexavalent Chromium For Reference Standard Certification And Quality Control Testing Using Speciated Isotope Dilution Mass Spectrometry,
2020
Duquesne University
Accurate Quantitation Of Hexavalent Chromium For Reference Standard Certification And Quality Control Testing Using Speciated Isotope Dilution Mass Spectrometry, James E. Henderson
Electronic Theses and Dissertations
The ability to perform accurate, repeatable, and defensible elemental and molecular speciated analysis is immensely significant for measurements that support human health, environmental science, and industry. This is especially true since trivalent chromium [Cr(III)] is necessary for proper nutrition, while hexavalent chromium [Cr(VI)] is extremely toxic, genotoxic, and carcinogenic. The main challenges associated with speciated analysis are related to reactive species that are continuously transformed or converted to other species during sample processing. Accurate determination of Cr(III) and Cr(VI) species require a method that is capable of monitoring and correcting for interconversion, bias, and instrumental error. Traditional quantitative methods, such …
Nanomaterial Composites Based On Potassium Hexaniobate, Perovskites, And Iron Triazole Spin Crossover Complexes,
2020
University of New Orleans
Nanomaterial Composites Based On Potassium Hexaniobate, Perovskites, And Iron Triazole Spin Crossover Complexes, Alexis A. Blanco
LSU New Orleans Theses and Dissertations
Development of novel materials with sought after properties has been the forefront in the field of nanomaterials. Hybrid nanomaterial architectures, or nanocomposites, is an important subgroup within the material chemistry umbrella. One such example of nanocomposite systems is peapod-like structures that are composed of 0D nanoparticles (“peas”) and 2D nanosheets (“pods”). Nanopeapods may display unique properties that were not attainable within individual components. BaTiO3 nanoparticles can be produced using solvothermal methods (20 h) in the presence of Ba(NO3)2, titanium (IV) butoxide, and oleic acid as the surfactant. Synthesis parameters were modified to allow for both …
Fluorinated Phthalonitriles And Phthalocyanines: Synthesis And Spectroscopic Properties,
2020
Seton Hall University
Fluorinated Phthalonitriles And Phthalocyanines: Synthesis And Spectroscopic Properties, Marius Pelmus
Seton Hall University Dissertations and Theses (ETDs)
Since their discovery at the beginning of the 20th century, phthalocyanines (Pc) have come a long way; today they are replacing the porphyrins (natural products) in most of their applications. The functionalization of the organic macrocycle, the use of different metals, and the change of the axial ligands resulted in Pc applications in a wide range of fields, ranging from photochemistry, paints, catalysis, to fuel cells and cosmetic products.
In Dr. Gorun’s group was developed a series of electron-deficient Pcs that benefit from a Teflon-like chemical shield, meant also to break the π-π interactions, namely the F64PcM …
A Library Of Low Molecular Weight Fluorescent Probes For The Detection Of Cu(Ii) And Fe(Iii) Ions,
2020
The University of Southern Mississippi
A Library Of Low Molecular Weight Fluorescent Probes For The Detection Of Cu(Ii) And Fe(Iii) Ions, Ashley Johnson
Dissertations
This dissertation reports the synthesis and photophysical properties of a family of rhodamine dyes (compounds 3.9-3.13 and 4.6). The rhodamine dyes are prepared in two steps, and fully characterized by ESI-MS (Low and High resolution), X-Ray crystallography, NMR spectroscopy, and FT-IR spectroscopy. The coordination environment of the low molecular weight fluorescent probes (LMFPs) was systematically changed to investigate the thermodynamic behavior between the LMFPs and an array of metal ions (Cu2+, Fe2+, and Hg2+ ions) in protic and aprotic solvent systems. Upon coordinating to metal ions, the π-conjugation of the LMFPs changed, resulting in …
The Utilization Of Metal-Ligand Cooperativity For Electrocatalytic Reduction And Catalytic Hydration.,
2020
University of Louisville
The Utilization Of Metal-Ligand Cooperativity For Electrocatalytic Reduction And Catalytic Hydration., Steven Cronin
Electronic Theses and Dissertations
Small molecules are building blocks for developing larger materials. These small molecules could be extremely small, such as hydrogen, or larger such as a nitrile, but their impact on the global economy is massive. This dissertation describes a catalyst for three reactions involving small molecules; 1) the hydrogen evolution reaction, 2) the carbon dioxide reduction reaction, 3) nitrile hydration. The catalyst Zn(DMTH) (DMTH = diacetyl-2-(4-methyl-3-thiosemicarbazonate)-3-(2-pyridinehydrazonato)) use “metal-ligand cooperativity” between the Lewis acid Zn(II) metal ion and an uncoordinated Lewis base nitrogen in the ligand framework to activate substrates. The complex has been analyzed via NMR, UV/Vis, single crystal X-ray crystallography, …
Design And Synthesis Of Novel No-Drug Hybrid Compound And Green Catalytic Activity Evaluation Of Synthesized Silver Nanoparticles-Halloysite Nanocomposite,
2020
University of New Orleans
Design And Synthesis Of Novel No-Drug Hybrid Compound And Green Catalytic Activity Evaluation Of Synthesized Silver Nanoparticles-Halloysite Nanocomposite, Majed Abdullah Bajaber
LSU New Orleans Theses and Dissertations
Acetaminophen is a well-known analgesic that can manage pain and reduce fever. SCP-1 is a derivative of acetaminophen that showed significantly reduced hepatotoxicity and nephrotoxicity comparative to acetaminophen. Nitric oxides have been well known to play a key role in a wide variety of physiological and pathophysiological important processes. It was therefore of interest to synthesize a nitric oxide donor linked to SCP-1 that could have enhanced analgesic and antipyretic activity. A furoxan CAS 1609 as NO-donor was synthesized and linked to SCP-1 successfully. The furoxan CAS 1609 was initially synthesized from tetronic acid to give 1,2- dioxime in 86 …
Selective Electrocatalytic Reduction Of Co2 To Co With Iron Nheterocyclic Carbene Complexes And Near-Infrared Absorbance Of Ruthenium(Ii) Photosensitizers Containing A Merocyanine Π-Acceptor,
2020
University of Massachusetts Boston
Selective Electrocatalytic Reduction Of Co2 To Co With Iron Nheterocyclic Carbene Complexes And Near-Infrared Absorbance Of Ruthenium(Ii) Photosensitizers Containing A Merocyanine Π-Acceptor, Peter Andrew Catsoulis
Graduate Masters Theses
The catalytic proton-coupled reduction of carbon dioxide into C-1 or “common engine” liquid fuels is currently a highly desirable and green approach to removing anthropogenic CO2 from the atmosphere. The most common approach to this is through electrocatalytic homogeneous reductions utilizing inorganic complexes as catalysts. Current research has moved towards the use of first-row transition metals in catalysts due to their high natural abundances and cheap cost. Iron porphyrin complexes have been vastly studied due to their high product selectivity and turnover frequencies. However, these complexes exhibit short lived activity because of competing reactions in their catalytic cycles, rendering them …
Study On Cation Exchange Of A Lead Coordination Polymer Targeting Dynamic Mixed Cation Doped And Mixed-Valent Coordination Polymers,
2020
Universiti Malaya
Study On Cation Exchange Of A Lead Coordination Polymer Targeting Dynamic Mixed Cation Doped And Mixed-Valent Coordination Polymers, Hamisu Aliyu Mohammed
Student Works (2020-2029)
Solid solution in Metal-Organic Coordination Polymers (MOCPs) is an emerging synthetic pathway for modifying chemical compositions and has been expansively investigated. It has been demonstrated to be an important tool for engineering novel functional materials that otherwise have not been synthesized via the conventional technique. Although stable solid material with variable functionalities and intriguing structural motifs could be engineered by judicious selection of multivariate metal centers and multifunctional ligands. However, solid solution featuring mixed valence in MOCP is rare. Motivated by the ability of Pb2+ to adopt range of coordination numbers (CN) and chemical environments (CE), in addition to its …
Multifunctional Metal-Organic Frameworks (Mofs) For Applications In Sustainability,
2020
University of South Florida
Multifunctional Metal-Organic Frameworks (Mofs) For Applications In Sustainability, Gaurav Verma
USF Tampa Graduate Theses and Dissertations
Climate change, affordable and clean energy, and responsible consumption and production are some of the important goals to be achieved for sustainable development. The current technologies used to address these challenges are energy and resource intensive. Furthermore, there are various limitations related to cost, storage, scalability and safety.Adsorbent materials are seen as a promising alternative remediation system due to their low energy consumption and minimal chemical waste production. However, most of the traditional adsorbents, such as activated carbon and zeolites lack the structural tunability to have long-term effectiveness and their use is limited. As discussed in Chapter 1, metal organic-frameworks …
Covalent Organic Frameworks As An Organic Scaffold For Heterogeneous Catalysis Including C-H Activation,
2020
University of South Florida
Covalent Organic Frameworks As An Organic Scaffold For Heterogeneous Catalysis Including C-H Activation, Harsh Vardhan
USF Tampa Graduate Theses and Dissertations
Linking small organic molecules into an extended solid usually afford disordered amorphous polymers. The instigation of order into such a material is of profound interest to induce inherent fine control of the overall structure. Covalent organic frameworks (COFs) are new class of porous crystalline material prepared by connecting organic building blocks via strong covalent bonds. The judicious choice of organic monomers can give rise to highly ordered and predictable frameworks with high crystallinity, surface area, and thermal/chemical stability. The role of connecting linkages such as B─O, C─C, C─N extends the principle of fundamental molecular covalent chemistry to the formation of …
Ru(Ii)-Diimine Complexes And Cytochrome P450 Working Hand-In-Hand,
2020
Genentech
Ru(Ii)-Diimine Complexes And Cytochrome P450 Working Hand-In-Hand, Celine Eidenschenk, Lionel Cheruzel
Faculty Publications, Chemistry
With a growing interest in utilizing visible light to drive biocatalytic processes, several light-harvesting units and approaches have been employed to harness the synthetic potential of heme monooxygenases and carry out selective oxyfunctionalization of a wide range of substrates. While the fields of cytochrome P450 and Ru(II) photochemistry have separately been prolific, it is not until the turn of the 21st century that they converged. Non-covalent and subsequently covalently attached Ru(II) complexes were used to promote rapid intramolecular electron transfer in bacterial P450 enzymes. Photocatalytic activity with Ru(II)-modified P450 enzymes was achieved under reductive conditions with a judicious choice of …
Synthesis, Structure Elucidation And Selected Biological Activities Of Ag(I) And Au(I) Complexes Constructed From Thiosemicarbazone And Phosphine Ligands,
2020
Universiti Malaya
Synthesis, Structure Elucidation And Selected Biological Activities Of Ag(I) And Au(I) Complexes Constructed From Thiosemicarbazone And Phosphine Ligands, Syahrina Nur ‘Ain Abdul Halim
Student Works (2020-2029)
New Ag(I) and Au(I) mixed ligand complexes were synthesised using thiosemicarbazone and phosphine in search of a new biologically active compounds. CHN elemental analysis, powder X-ray diffraction (PXRD), single crystal X-ray diffraction as well as several spectroscopic techniques such as FT-IR, Energy-dispersive X-ray (EDX), 1H, 13C, and 31P{1H} NMR were performed to elucidate the structure of these complexes. Elemental analysis suggested that the stoichiometry of the complexes formed by the reaction of Ag nitrate with thiosemicarbazone in the presence of phosphine was indeed 1:2:1 molar ratio, while for the Au to be in 1:1:1 molar ratio. The Ag and Au …
