Chemistry Commons^™

Phenanthroline-Catalyzed 1,2-Cis Glycosylation: Scope And Mechanism, Jiayi Li

Wayne State University Dissertations

Phenanthroline, a rigid and planar organic compound with two fused pyridine rings, has been used as a powerful ligand for metals and a binding agent for DNA/RNA. We recently discovered that phenanthroline could be used as a nucleophilic catalyst to access high yielding and diastereoselective α-1,2-cis glycosides through the coupling of hydroxyl acceptors with α-glycosyl bromide donors. The utility of the phenanthroline catalysis is expanded to sterically hindered hydroxyl nucleophiles and chemoselective coupling of an alkyl hydroxyl group in the presence of a free C1-hemiacetal functionality. In addition, the phenanthroline-based catalyst has a pronounced effect on site-selective couplings of triol …

Lanthanide Coordination Chemistry In Rare-Earth Element Extraction And Photocatalysis, Jessica Hovey

Wayne State University Dissertations

This thesis outlines projects pertaining to the extraction, enrichment, and use of rare-earth elements in the trivalent and divalent states through the modification of coordination chemistry. Modulating the coordination environment can impact the selectivity of rare-earth elements in solid-liquid enrichment through the adjustment of donor atoms, denticity and pKa values as detailed in Chapter 1. Changes in coordination environment, such as to the identity of donor atoms, can lead to major differences in properties such as luminescence. The studies reported in this thesis contribute to the body of knowledge surrounding the use of coordination chemistry for both the solid–liquid extraction …

Development Of Carbohydrate-Based Antibiotics And Metabolic Chemical Reporters, Courtney Kondor

Wayne State University Dissertations

CHAPTER 1: Multidrug-resistant bacteria is a threat to public health and there is a need for the development of new antibiotics to fight bacterial resistance. Aminoglycoside antibiotics are attractive to researchers due to their lack of known drug related allergies, low cost, and broad spectrum of activity; however, they can cause nephrotoxicity and ototoxicity in patients. We modified the 2-deoxystreptamine ring of paromomycin to make the drug more flexible and potentially more selective for the bacterial ribosomal A-site to circumvent off-target effects that cause ototoxicity. However, we found that our compound, paromomexin, was significantly less active than paromomycin in all …

Electrochemical Gelation Of Metal Chalcogenide Quantum Dots, Chathuranga Chinthana Hewa Rahinduwage

Wayne State University Dissertations

Quantum dots (QDs) are attractive because of their unique size-dependent optical and electronic properties and high surface area. They are tested in research for diverse applications, including energy conversion, catalysis, and sensing. Assembling QDs into functional solid-state devices while preserving their attractive properties is a challenge. Methods currently under the research are not effective in directly fabricating QDs onto devices, making large area assemblies, maintaining the high surface area by forming 3D porous structures, and conducting electricity for applications such as sensing. QD gels are an example of QD assemblies that consist of a 3D porous interconnected QD network. They …

Extending Plasma Proteome Coverage To Enable Biomarker Discovery, Jordan Bruce Burton

Wayne State University Dissertations

Two features make plasma a valued source of health information: First, plasma contains secreted proteins from all tissues in the body and can, therefore, provide information about the health status of all tissues. Second, plasma is available in large quantity using a minimally invasive procedure that is well tolerated. The status of plasma as a valued source of health information is matched by the difficulty in extracting proteome information from the samples. Using state of the art instrumentation a standard analysis of plasma yields quantitative information on approximately 300 proteins. Extreme fractionation strategies coupled with increased mass spectrometry time extends …

Development Of Terpyridine-Based Metallosurfactants For Directional Electron Tunneling, Samudra Subashini Amunugama

Wayne State University Dissertations

The molecular electronics field is a multidisciplinary area that addresses the utilization of molecules as the basic unit of electronic components. Depending on the characteristics of the molecules, they can function as transistors, wires, switches, and memory cells. This field has attracted significant interest from the scientific community due to the increasing number of issues associated with the miniaturization process of microelectronic devices and the desirability of using molecules in electronic circuits. The research work discussed in this dissertation thesis is focused on the design and development of terpyridine-based metallosurfactant as prospective candidates for molecular electronics. Since rectifiers are pivotal …

Synthesis Of Molybdenum Containing Thin Films Using Organic Reducing Agents And Synthesis Of Magnesium Silyl Intermediate Complexes For Use In Atomic Layer Deposition, Michael David Overbeek

Wayne State University Dissertations

Thin films of a variety of materials have shown great potential in the fields of microelectronics, catalysis, and energy applications. Vapor deposition methods, including PVD and CVD, have been traditionally used as the primary method to deposit these thin films. However, these methods do not provide the necessary thickness uniformity and conformality needed for future uses of these thin films as they shrink to smaller dimensions. ALD provides a high degree of uniformity and conformality due to the intrinsic nature of the self-limited reaction mechanism of an ALD process.

The research herein focuses on two metals that have untapped potential …

Electrochemistry Of Bubbles: Developing New Sensors, Promoting Gas Evolution Reactions, And Extraction Of Rare Earth Elements, Ruchiranga R. Ranaweera

Wayne State University Dissertations

This dissertation presents new analytical, electrocatalysis, and separation strategies that utilize bubble behaviors in different electrochemical systems. The first part of this dissertation focuses on the method development for PFAS preconcentration and detection. First, we present the bubble-nucleation-based electrochemical method for the selective and sensitive detection of surfactants. Our method utilizes the high surface activity of surfactant analytes to affect the electrochemical bubble nucleation and then transduces the change in nucleation condition to an electrochemical signal for determining the surfactant concentration. Using this method, we demonstrate the quantitation of perfluorinated surfactants in water, a group of emerging environmental contaminants, with …

Microfluidic Thermal Gel Electrophoresis For Native Protein Analysis, Shakila Hasanthika Peli Thanthri

Wayne State University Dissertations

Proteins must be in their native states to carry out their intended biological functions. Native protein structure requires that proteins be folded into the correct conformations and possess the necessary post-translational modifications (PTMs). These higher-order structures are critical to ensuring that proteins are biologically active and properly interact with neighboring molecules. However, assessing folding conformations and modified protein variants is challenging, and routine sample validation techniques like polyacrylamide gel electrophoresis (PAGE) are not capable of analyzing higher-order structures. Gradient PAGE gels can determine the molecular weight of proteins over a wide mass range, but protein separation resolutions are poor because …

Synthesis And Reactivity Of Metal Bis(Alkoxide) Complexes In Nitrene Coupling And Polymerization Of Polar Monomers, Duleeka Chamini Wannipurage

Wayne State University Dissertations

The nitrene homocoupling to produce azoarenes was done using two different iron (II) alkoxide complexes, Fe(OCtBu2(3,5-Ph2C6H3)2(THF)2 and Fe[OO]Ph(THF)2. Due to the steric bulkiness of HOCtBu2(3,5-Ph2C6H3 ligand, this complex exhibited selectivity for the bis(alkoxide) ligation; no tris(alkoxide) complexes were observed. As a result, both bulky and non-bulky aryl nitrenes are coupled with Fe(OCtBu2(3,5-Ph2Ph)2(THF)2, albeit the coupling of the less bulky substrates requires higher temperatures and longer reaction times. Stoichiometric reactions of Fe(OCtBu2(3,5-Ph2C6H3)2(THF)2 with non-bulky aryl azides led to the observation of the iron(III) tetrazene radical anion complexes, that can produce azoarene products after heating. Tetrazene complexes likely serve as a “masked …

Thermal Atomic Layer Deposition Of Titanium Nitride Films: Synthesis And Characterization Of Novel Titanium Precursors, Anuththara Chalani Upeksha Abesinghe Arachchige

Wayne State University Dissertations

Due to the continuous miniaturization of microelectronic devices, robust deposition techniques are required which can provide continuous and conformal thin films even in high aspect ratio structures. Atomic Layer Deposition (ALD) is an excellent choice of deposition technique as it is capable of providing perfect film coverage. Because of its self-limited growth mechanism, ALD can afford sub-nanometer thickness control. Precursors used in ALD should be volatile, thermally stable at the deposition temperature, and highly reactive towards the co-regent. Traditionally, ALD has been used to grow metal oxide films. However, the microelectronics industry now demands ALD for metals and metal nitrides. …

Induction And Prevention Of Electron Transport In Langmuir-Blodgett Films Of 3d-Based Metallosurfactants: Studies On Current Rectification And Corrosion Inhibition, Aldora Devale Kapuralalage Isuri Weeraratne

Wayne State University Dissertations

The work reported in this thesis focused on the use of redox-active metallosurfactants for current rectification and redox-innocent metallosurfactants for corrosion inhibition. These studies were done based on the hypothesis that redox-active metallosurfactnats can promote electron transport, while redox-innocent metallosurfactants can hinder electron transport. As such, new redox-active phenolate based iron(III), chromium(III), oxovanadium(IV) and redox-innocent gallium(III) and zinc(II) complexes were synthesized and characterized for the aforementioned applications. First, we studied the current rectification ability of a homobimetallic iron(III) hydrophobe with [N4O6] ligand environment. This complex displayed rectification with rectification ratio ranges from 2.6 to 9.8 between -2.0 and 2.0 V …

Development And Application Of Chemical Tools To Identify Kinase-Substrate Interactions, Aparni Kithulgoda Gamage

Wayne State University Dissertations

Post translational modifications regulate a variety of biological processes inside the cell.Protein phosphorylation is one such PTM modification catalyzed by protein kinases, which aid to transfer a signal from one place to another inside the cell. However, irregularities in kinase-mediated signaling are often implicated in many diseases, making kinases effective drug targets. To understand kinase-related disease formation and to discover drugs to treat these diseases, it is crucial to have a clear understanding on kinase-mediated cell signaling networks. A current gap in the kinase biology field is a lack of tools to identify which kinase phosphorylates which protein substrate inside …

Influence Of Conformational Restriction On The Antibacterial Activity And Ribosomal Selectivity Of Aminoglycoside Antibiotics, Michael Gabriel Pirrone

Wayne State University Dissertations

The ever-increasing threat posed by multidrug-resistant infectious bacteria necessitates

the development of novel antibiotics. Aminoglycoside antibiotics are growing in interest due to

their broad spectrum of activity, lack of known drug related allergies, low manufacturing cost,

and their well-studied mechanism of action. The simplification of rational drug design due to the

well-studied mechanism of action is the key to overcoming the issues presented by these drugs,

namely ototoxicity and nephrotoxicity.

A study of the effect of the conformation of the aminoglycoside ring I side chain is

described wherein it was discovered that an increase in a particular conformation augments the …

Exploring The Scope And Limitations Of The Oxidative Deamination Of N-Acetyl Neuraminic Acid, Mohammed Bakr Hawsawi

Wayne State University Dissertations

Sialic acids are molecules of importance in the fields of carbohydrate chemistry and glycoscience, and their diversity make them even more attractive to scientific research. Modifications of sialic acid derivatives may lead to several biological and chemical features that can be utilized for medicinal purposes. The modern drug therapy is dependent on the chemical discoveries of potent and effective molecules. N-Acetyl neuraminic acid is the parent and most common molecule in sialic acid family that received considerable attention in glycochemical research. This dissertation explores the scope as well as the limitations of the Zbiral oxidative deamination of N-acetyl neuraminic acid …

Thermal Atomic Layer Deposition Of Silver Metal Films: Synthesis And Characterization Of Thermally Stable Silver Metal Precursors, Harshani Jayabahu Arachchilage

Wayne State University Dissertations

ABSTRACT

THERMAL ATOMIC LAYER DEPOSITION OF SILVER METAL FILMS: SYNTHESIS AND CHARACTERIZATION OF THERMALLY STABLE SILVER METAL PRECURSORS

by

HARSHANI JAYABAHU ARACHCHILAGE

August 2020

Advisor: Professor Charles H. Winter

Major: Chemistry (Inorganic)

Degree: Doctor of Philosophy

Traditional film deposition techniques such as PVD and CVD are widely used in the microelectronics industry. However, the lack of thickness control and conformality requirements limit these techniques for current and future applications. By contrast, ALD offers the deposition of ultra-thin conformal films with accurate thickness control due to the self-limiting growth behavior. Ag metal has the lowest resistivity (1.59 µΩ cm) of all …

The Effects Of Coordination Environment On The Spectroscopic And Electrochemical Properties Of Divalent Lanthanides, Tyler C. Jenks

Wayne State University Dissertations

The research projects in this dissertation pertain to the properties of molecular divalent lanthanide complexes with a focus on luminescence properties in solution. Most available research in lanthanide chemistry focuses on either the trivalent oxidation state or the divalent oxidation state in solid inorganic host matrices. The results described herein contribute to the body of knowledge regarding the effects of coordination environment on the spectroscopic and electrochemical properties of divalent lanthanides in solvated molecular complexes.

The divalent-europium-containing complex Eu(II)23 was evaluated as a visible-light-excited photoredox precatalyst. Stoichiometric and catalytic carbon–carbon bond forming reactions of Eu(II)23 with benzyl chloride in the …

Parahydrogen Hyperpolarized Multi-Nuclear Contrast Agents For Potential Mri Applications, Nuwandi Maduranga Ariyasingha Uragoda Wiyannalage

Wayne State University Dissertations

ABSTRACT

PARAHYDROGEN HYPERPOLARIZED MULTI-NUCLEAR CONTRAST AGENTS FOR POTENTIAL MRI APPLICATIONS

by

NUWANDI M. ARIYASINGHA

December 2020

Advisor: Dr. Eduard Chekmenev

Major: Chemistry (Physical)

Degree: Doctor of Philosophy

There have been numerous studies to develop fast, cost effective hyperpolaried (HP) contrast agents with higher polarization values that can be potentially employed for magnetic resonance clinical imaging. Some of the currently used contrast agents are based on 129Xe hyperpolarized nucleus. However, one of the problems associated with this approach, is the high cost of the produced hyperpolarized contrast agents. In addition, the other important practical problem is that the currently used clinical …

Non-Canonical Targets, Reaction Kinetics, And Cellular Potency Of Amino Acid-Linked Platinum(Ii) Compounds, Bett Kimutai

Wayne State University Dissertations

DNA serve as an ideal target where drugs such as cisplatin (cisPt) bind and exert their anticancer activities. CisPt is known to preferentially coordinate with DNA leading to formation of cisPt-deoxyguanosine (dGuo) adducts. The adducts distort the DNA structure and contribute to inhibition of DNA-mediated cellular functions and ultimately cancer cell death. Despite its utilization as an anticancer drug, cisPt has a number of drawbacks, which include toxic side effects and cellular resistance. Resistance occurs through processes such as repair of damaged DNA and inactivation of cisPt present in the cell. To overcome these challenges, the aim of this thesis …

Reactions Of First-Row Transition Metal Complexes In Bis(Alkoxide) Ligand Environments With Diazoalkanes: Formation Of Carbenes Versus Reductive Coupling To Form Bridging Tetrazenes, Amanda Grass

Wayne State University Dissertations

This dissertation focuses on the design and reactions of novel late transition metal carbene complexes featuring alkoxide ligand environments. The high-valent cobalt carbene Co(OR)2(=CPh2) (OR = OCtBu2Ph), featuring short Co=C bond of 1.773(3) Å, was previously reported from the reaction of Co(OR)2(THF)2 with diphenyldiazoalkane. Magnetic and spectroscopic (EPR) studies demonstrated Co(OR)2(=CPh2) to be a low-spin S = ½ complex. Computational studies, in agreement with experimental data, suggested that the electronic structure of Co(OR)2(=CPh2) lies between intermediate spin Co(III) anti-ferromagnetically coupled to a carbene radical and a Co(IV) alkylidene. This dissertation began with investigation of this complex in carbene transfer reactivity. …

Synthesis Of Bradyrhizose And The Equatorial Glycosides Of 3-Deoxygenation-D-Mango-Oct-2-Ulosonic Acid, Philemon O. Ngoje

Wayne State University Dissertations

ABSTRACT

SYNTHESIS OF BRADYRHIZOSE AND THE EQUATORIAL GLYCOSIDES OF 3- DEOXY-D-MANNO-OCT-2-ULOSONIC ACID

Chapter one provides a general view on the background to the research in two parts. The first part begins with an introduction on the significance of the lectin-carbohydrate interactions in leguminous plants. Then the structure and role of O-antigen lipopolysaccharides in the symbiotic nitrogen cycle, and the mechanism and significance of the cycle in leguminous plants growth are introduced. The role, isolation and characterization of bradyrhizose are also introduced; and the previous syntheses of bradyhizose and of related bicyclic compounds presented.

The second part of chapter one starts …

Harnessing The Reactivity Of The N-Methyl Diaminobenzoyl Linker To Access C-Terminally Modified And Macrocyclic Peptides, Christine Arbour

Wayne State University Dissertations

This thesis describes the exploration of accessing C-terminally modified and macrocyclic peptides through N-acyl urea (MeNbz) displacement. Prior to this work, the diaminobenzoyl linker was used to access thioesters for native chemical ligation. Only solution-phase displacement of the N-acyl urea with thiol nucleophiles was previously reported.

The N-Me-diaminobenzoyl (MeDbz) linker was initially used to access C-terminal glycine esters, amides, and acids from a single peptide substrate. This led to the total synthesis of Conopressin G and two analogs. The propensity of the C-terminal cysteine residue to undergo epimerization was investigated using this strategy. After optimization, C-terminal cysteine esters, amides, and …

Influence Of Side Chain Conformation On The Mechanism(S) Of Glycosylation Reactions; Investigation Of Sialidation Reaction Mechanism(S) By Kinetic Studies, Harsha Chandhana Amarasekara

Wayne State University Dissertations

Glycosylation, being the key reaction of glycobiology and carbohydrate chemistry, demands robust and stereoselective glycosylation methods. The rational development of such methods necessitates knowledge of the glycosylation reaction mechanism and the factors influencing glycosylation reactions. The work discussed in this dissertation is focused on studying glycosylation reaction mechanisms and exploring the key factors influencing them.

Chapter one reviews the background to the research, starting with a brief introduction of the significance of carbohydrates as structural and energy-storage materials. The significance of cell surface carbohydrates and their roles in communication and related processes are discussed along with examples of their applications …

Binary And Ternary Transition Metal Pnictide Nanoparticles And Their Three-Dimensional Assemblies: Towards Promising Magnetic Refrigeration Materials, Malsha Anuradhi Hettiarachchi

Wayne State University Dissertations

BINARY AND TERNARY TRANSITION METAL PNICTIDES NANOPARTICLES AND THEIR THREE DIMENSIONAL ASSEMBLIES: TOWARDS PROMISING MAGNETIC REFRIGERATION MATERIALS

by

MALSHA ANURADHI HETTIARACHCHI

May 2019

Advisor: Dr. Stephanie L. Brock

Major : Chemistry

Degree : Doctor of Philosophy

Bulk MnAs has been recognized as a potential MR material with large MCE. However, the magnetic transition of bulk MnAs suffers from a large thermal hysteresis of 6 K precluding efficient MR cycling, and the magnetic entropy change associated with the phase transition is limited to a narrow temperature range, making the temperature control window very small. Solid solutions of MnAs, synthesized by both …

Nonadiabatic Dynamics: A Semiclassical Approach, Ruixi Wang

Wayne State University Dissertations

Nonadiabatic dynamics has been an essential part of quantum chemistry since the 1930’s. Nonadiabatic effects play a crucial role in photo-physical and photo-chemical reactions for both small and large molecules in both gas and condensed phases. Modeling dynamics of photoinduced reactions has been a new frontier of chemistry. Many dynamical phenomena, such as intersystem crossing, non-radiative relaxation, and charge energy transfer, require a nonadiabatic description which incorporates transitions between electronic states.

In Chapter 2, the property of scattering region in the semiclassical limit is investigated. We suggest that a nuclear wavepacket close enough to the conical intersection will propagate ballistically …

Rare-Earth-Activated Group Vi D0 Metal Oxides As Thermosensitive Phosphors, Samarage Sameera Perera

Wayne State University Dissertations

ABSTRACT

RARE-EARTH-ACTIVATED GROUP VI d0 METAL OXIDES AS

THERMOSENSITIVE PHOSPHORS

by

SAMARAGE SAMEERA PRASAD PERERA

AUGUST 2019

Advisor: Dr. Federico A. Rabuffetti

Major: Chemistry

Degree: Doctor of Philosophy

Thermosensitive phosphors are solid-state materials that demonstrate distinct dependence of luminescence emission on temperature. These materials enable optical temperature sensing in environments where conventional thermometry is not possible (e.g., gas turbines, combustion engines, surface temperature distributions). However, the design of thermosensitive phosphors that show adequate sensitivity and low thermal quenching in the intermediate temperature range (i.e., 500–1000 K) remains challenging. This challenge can be addressed by understanding how to rationally manipulate the …

Atomic Layer Deposition (Ald) And Atomic Layer Etching (Ale) Of Thin Films: Synthesis And Characterization Of A New Class Of Ald Precursors, Ald Of Pralo3 Thin Films, And Thermal Ale Of Cobalt Metal Films, Wathsala Lakmali Iwadunna Waduge

Wayne State University Dissertations

ABSTRACT

ATOMIC LAYER DEPOSITION (ALD) AND ATOMIC LAYER ETCHING (ALE) OF THIN FILMS: SYNTHESIS AND CHARACTERIZATION OF A NEW CLASS OF ALD PRECURSORS, ALD OF PrAlO3 THIN FILMS, AND THERMAL ALE OF COBALT METAL FILMS

by

WATHSALA LAKMALI IWADUNNA WADUGE

February 2019

Advisor: Professor Charles H. Winter

Major: Chemistry (Inorganic)

Degree: Doctor of Philosophy

ALD is an attractive thin film deposition technique due to its unique self-limiting growth behavior and the ability to achieve Angstrom level thickness control. Alternative thin film deposition techniques such as CVD and PVD are unable to attain the conformal and Angstrom level film growth which …

Modification Of Bruker Amazon Etd And Solarix Mass Spectrometers Towards Infrared Multiple Photon Dissociation: Structural Characterization Of Modified Nucleosides, Lucas Ash Hamlow

Wayne State University Dissertations

Infrared ion spectroscopy has become an increasingly powerful tool for examining

the intrinsic structures of gas-phase ions. Infrared multiple photon dissociation (IRMPD)

action spectroscopy has been particularly successful. Several free electron laser (FEL)

facilities across the world have helped facilitate the growth of the IRMPD technique and

increasing interest has driven the development of more accessible IRMPD

instrumentation. The development of one such IRMPD instrumentation system is

described in this work, based around commercially available 3D quadrupole ion trap mass

spectrometers and Fourier-transform ion cyclotron resonance mass spectrometers.

The intrinsic gas-phase structures of nucleic acid monomers have been

extensively studied …

Synthesis, Structure, And Luminescence Properties Of Rare-Earth-Doped Alkaline-Earth Fluorohalide Upconverting Nanocrystals, Kumuduni Tauni Dissanayake

Wayne State University Dissertations

The major scientific problems that associated with the state-of-the-art upconverting nanocrystal system (rare-earth-doped β-NaYF4) are lower quantum efficiency, lack of full-spectrum color tunability, and difficulty in achieving single-band red emission. The major scientific strategies that employed to address these scientific problems are based on nanostructuring, tuning rare-earth concentration, and tuning host chemical composition. The reported articles during the past few decades clearly illustrated that nanostructuring and tuning rare-earth concentration hadn’t bought considerable contribution to synthesize efficient and color-tunable upconverting nanocrystal systems. However, the ability to tune the chemical composition of the host to design efficient and color-tunable upconverting nanocrystal system …

Functional Characterization Of Accessory Proteins And Novel Activities In Direct And Indirect Trna Aminoacylation, Udumbara Menike Rathnayake

Wayne State University Dissertations

Indirect tRNA aminoacylation is essential for most bacteria and archaea, particularly when these species do not have genes encoding asparaginyl- and/or glutaminyl-tRNA synthetase (AsnRS and GlnRS). In the absence of AsnRS, the first step in Asn-tRNAAsn synthesis involves misacylation of tRNAAsn with aspartate to produce Asp-tRNAAsn; this reaction is catalyzed by a non-discriminating aspartyl-tRNA synthetase (ND-AspRS). Subsequently, in bacteria, an amidotransferase called GatCAB converts Asp-tRNAAsn to Asn-tRNAAsn. An analogous, two-step processes exist to produce Gln-tRNAGln. In this case, a non-discriminating glutamyl-tRNA synthetase (ND-GluRS) misacylates tRNAGln to produce Glu-tRNAGln, which is then converted to Gln-tRNAGln by GatCAB. The central hub of …