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Full-Text Articles in Physical Sciences and Mathematics

Design Of Ruthenium(Ii) Polypyridyl Complexes For Effectively Caging Nitriles And Aromatic Heterocycles, Ao Li Jan 2018

Design Of Ruthenium(Ii) Polypyridyl Complexes For Effectively Caging Nitriles And Aromatic Heterocycles, Ao Li

Wayne State University Dissertations

ABSTRACT

DESIGN OF RUTHENIUM(II) POLYPYRIDYL COMPLEXES FOR EFFECTIVELY CAGING NITRILES

AND AROMATIC HETEROCYCLES

by

AO LI

May 2018

Advisor: Dr. Jeremy Kodanko

Major: Chemistry

Degree: Doctor of Philosophy

Ru(II) polypyridyl complexes have been frequently employed in the caging and photorelease of biologically active compounds. Traditional photocaging groups derived from Ru(II) have been largely based on bi- or tridentate ancillary ligands, and those bearing ancillary ligands with high-denticities are yet to be developed. Exploring Ru(II) polypyridyl complexes possessing ancillary ligands with high-denticities provides insight into the photophysical and photochemical properties of ruthenium complexes, which creates novel prospects in the design of …


Functional Study Of Smyd2 Glutathionylation In Cardiomyocytes, Dhanushka Nalin Perera Munkanatta Godage Jan 2018

Functional Study Of Smyd2 Glutathionylation In Cardiomyocytes, Dhanushka Nalin Perera Munkanatta Godage

Wayne State University Dissertations

Reactive oxygen species (ROS) are important signaling molecules that contribute to the etiology of multiple muscle-related diseases, including cardiomyopathy and heart failure. There is emerging evidence that cellular stress can lead to destabilization of sarcomeres, the contractile unit of muscle. However, it is not completely understood how cellular stress or ROS induce structural destabilization of sarcomeres or myofibrils. Protein glutathionylation is one of the major protein cysteine oxidative modifications that play an important role in redox signaling and oxidative stress. In this report, we used a clickable glutathione approach in a cardiomyocyte cell line, and found that SET and MYND …


Toward Better Keys For Lectin Locks: Glycoconjugates Versus Glycomimetics, Peng Wen Jan 2018

Toward Better Keys For Lectin Locks: Glycoconjugates Versus Glycomimetics, Peng Wen

Wayne State University Dissertations

As one of the four major classes of macromolecule in living systems, the roles of carbohydrates as energy storage substances and structural components have long been recognized. However, the unique role of carbohydrates in cellular recognition processes has only been scrutinized since the 1960s, thanks to the progress in the research in both cell surface carbohydrates and carbohydrate-binding proteins (lectins). The advances in the research of such process demand the use of carbohydrates as basic tools. Therefore, the primary goal of glycochemistry has been to obtain complex carbohydrates and their analogs effectively. One common approach to the problem involves the …


Applications Of Molecular And Quantum Mechanical Methods For Studying The Chemical Reactions Of Inorganic And Organic Systems, Yi-Jung Tu Jan 2018

Applications Of Molecular And Quantum Mechanical Methods For Studying The Chemical Reactions Of Inorganic And Organic Systems, Yi-Jung Tu

Wayne State University Dissertations

Computational studies can assist chemists to interpret experimental observations and to predict the properties and behaviors of molecules. The work presented in this dissertation applies different computational methods to study the molecular properties and reaction paths for various inorganic and organic systems. The second and third chapters discuss the force field development using “Gaussian Electrostatic Model (GEM)” and its amenability for use in the AMOEBA force field. The forth and fifth chapters discuss the density functional theory (DFT) studies of photodissociation behaviors for inorganic molecules. The sixth chapter explores the oxidation mechanisms of ascorbic acid and its antioxidant properties in …


3d Momentum Imaging Spectroscopy Probing Of Strong-Field Molecular And Surface Dynamics, Lin Fan Jan 2018

3d Momentum Imaging Spectroscopy Probing Of Strong-Field Molecular And Surface Dynamics, Lin Fan

Wayne State University Dissertations

Electron-ion coincidence measurements in combination with 3-dimensional (3D) momentum imaging can provide comprehensive 3D-momentum information to unravel multichannel photoionization/dissociation processes, and thus is an effective tool to investigate atomic/molecular dynamics. A camera-based 3D coincidence momentum imaging system and the velocity mapping imaging (VMI) based machine were introduced in Chapter 2. Studies of strong field dissociative single and double ionization of relatively large molecules camphor and 2-phenylethyl-N, N-dimethylamine (PENNA) were carried out and illustrated in Chapter 3. We demonstrated the main products of double ionization of PENNA were singlet diradicals. In Chapter 4, a novel angle resolved-photoemission spectroscopy based on VMI …


Design And Synthesis Of Oligo-(3,5-Dithio-Β-D-Glucopyranoside) As Β-(1→3)-Glucan Mimetics, Xiaoxiao Liao Jan 2018

Design And Synthesis Of Oligo-(3,5-Dithio-Β-D-Glucopyranoside) As Β-(1→3)-Glucan Mimetics, Xiaoxiao Liao

Wayne State University Dissertations

This dissertation presents the design and synthesis of oligo-(3,5-dithio-β-D-glucopyranoside) as β-(1 → 3)-D-glucan mimetics. The synthesized dimeric, trimeric and tetrameric mimetics were tested for their binding affinities to Dectin-1 and CR3 and their abilities to activate phagocytosis and pinocytosis.

The first chapter gives an introduction of β-(1 → 3)-D-glucan. It gives an introduction about the structure and origin of β-(1 → 3)-D-glucan as well as the immunostimulating effect of natural β-(1 → 3)-D-glucan. The study of interaction between β-(1 → 3)-D-glucan and the receptors leads to a conclusion that the hydrophobicity of β-(1 → 3)-D-glucan is crucial to its immunostimulating …


Modification Of 4,5- Aminoglycosides To Overcome Drug Resistance Bacteria And Toxic Side Effect, Guanyu Yang Jan 2018

Modification Of 4,5- Aminoglycosides To Overcome Drug Resistance Bacteria And Toxic Side Effect, Guanyu Yang

Wayne State University Dissertations

ABSTRACT

MODIFICATION OF 4,5- AMINOGLYCOSIDES TO OVERCOME DRUG RESISTANCE BACTERIA AND TOXIC SIDE EFFECT

by

Guanyu Yang

September 2018

Advisor: Professor David Crich

Major: Chemistry

Degree: Doctor of Philosophy

Infectious diseases causing by antibiotic resistant pathogen are one of the major threat to human health and society today. Many researchers tried to develop next generation of antibiotics by reinvesting the existing antibacterial drugs. Aminoglycosides have long been used as highly potent and broad-spectrum antibiotics for treating bacterial infections. But their side effect, especially the irreversible ototoxicity, and the fast-growing resistant problem limit their application. The goal of this research was …


Stereoselective Synthesis Of Legionaminic Acid And Pseudaminic Acid Glycosides, Bibek Dhakal Jan 2018

Stereoselective Synthesis Of Legionaminic Acid And Pseudaminic Acid Glycosides, Bibek Dhakal

Wayne State University Dissertations

Legionaminic acid (Leg) and pseudaminic acid (Pse) are deoxy acetamido analogues of the most common sialic acid, N-acetylneuraminic acid (NeuAc) that are found in microorganisms. Leg and Pse are rare but important class of sialic acids, as their glycosides are found in lipopolysaccharides and glycoproteins of several pathogenic Gram-negative bacteria including Pseudomonas aeruginosa, Legionella pneumophila serogroup 1, Campylobacter jejuni, and Campylobacter coli. As such, the stereoselective glycosylation of the equatorial Leg and Pse donors, and the role played by their side chain conformations in anomeric reactivity and selectivity are the focus of this thesis.

Chapter two describes the synthesis of …


Hydroxylamines And Hydrazines As Surrogates Of Sp3 Carbons In Medicinal Chemistry, Sandeep Dhanju Jan 2018

Hydroxylamines And Hydrazines As Surrogates Of Sp3 Carbons In Medicinal Chemistry, Sandeep Dhanju

Wayne State University Dissertations

Current compound libraries that are used in high-throughput screening (HTS) are populated by low molecular weight and relatively planar compounds with high sp2 character and little stereochemical complexity. Unfortunately, such planar compounds cover only a very small corner of chemical space. In order to increase the diversity, structurally complex molecules with high fractions of sp3-hybridized atoms should be included in compound libraries. However, generating a large number of architecturally complex molecules using the current organic synthesis toolbox is considered tedious due to the requirement of multi-step synthesis. Recognizing this need, several creative strategies, like diversity-oriented synthesis, have been developed with …


Chemical And Physical Studies Of Charge Transfer Excited States Of Ruthenium Complexes With Aromatic Ligands, Marim Khalifa Alnaed Jan 2018

Chemical And Physical Studies Of Charge Transfer Excited States Of Ruthenium Complexes With Aromatic Ligands, Marim Khalifa Alnaed

Wayne State University Dissertations

The 3MLCT excited states generated from tris-bipyridineruthenium(II), [Ru(bpy)3]2+ and related complexes was ionized by 405 nm irradiation in ambient, acidic aqueous solutions. The photoionization product was Ru(bpy)3]3+ and an electron with a quantum yield of about 0.040.02 in 0.5 M acid. However, 532 nm radiation does not induce photoionization, and it generates the 3MLCT excited state that can be photoionized by 405 nm irradiation. The proton is a very good electron scavenger, and the rate of phoionization of the 3MLCT excited state was determined to be acid dependent and it increased about ten-fold for acid concentrations beween 0.001 and 4 …


Carbazole Based Multifunctional Dopamine Agonists And Related Molecules As Potential Symptomatic And Disease Modifying Therapeutic Agents For Parkinson’S Disease, Asma S.Mohamed Elmabruk Jan 2018

Carbazole Based Multifunctional Dopamine Agonists And Related Molecules As Potential Symptomatic And Disease Modifying Therapeutic Agents For Parkinson’S Disease, Asma S.Mohamed Elmabruk

Wayne State University Dissertations

Parkinson’s disease (PD) is a progressive neurodegenerative disease that develops from gradual depletion of dopamine (DA) and dopaminergic neurons in the substantia nigra pars compacta (SNc) with the accumulation of intraneuronal proteinaceous matter named as Lewy bodies. The four cardinal symptoms associated with PD are tremor, rigidity, bradykinesia, and postural instability. Although the exact mechanism and etiology of PD are not fully understood, several factors have been implicated in the pathogenesis and progression of PD including protein aggregation, oxidative stress, mitochondrial dysfunction, environmental, and genetic factors.

The current therapy of Parkinson’s disease is categorized into four classes: levodopa, DA agonists, …


Cation Clock Reactions For The Determination Of Relative Reaction Kinetics In Glycosylation Reactions, Philip Adero Jan 2018

Cation Clock Reactions For The Determination Of Relative Reaction Kinetics In Glycosylation Reactions, Philip Adero

Wayne State University Dissertations

This dissertation presents the development of cyclization reactions as clocks for the determination of the molecularity of glycosylation reactions in individual pyranoside systems and extends it to the arabinofuranoside systems. It also describes the development of selective hydrogenolytic cleavage of naphthylmethyl ethers in the presence of sulfides.

The first part of chapter one gives an overview of the significance of glycochemistry and the challenges involved. The second part describes some selected glycosylation methods and extends this to the general mechanistic studies of glycosylation. This is followed by the discussion of the general clock reactions in literature which initiates a further …


Synthesis Of Volatile And Thermally Stable Aluminum Hydride Complexes And Their Use In Atomic Layer Deposition Of Metal Thin Films, Kyle Blakeney Jan 2018

Synthesis Of Volatile And Thermally Stable Aluminum Hydride Complexes And Their Use In Atomic Layer Deposition Of Metal Thin Films, Kyle Blakeney

Wayne State University Dissertations

The research discussed in this dissertation spans both synthetic inorganic and nanomaterials chemistry. Aluminum hydride complexes have been synthesized and characterized which are highly volatile and thermally stable and their potential as reducing agents for ALD of electropositive metal and metal-containing films was evaluated. A major discovery has been the deposition of aluminum metal films by thermal ALD using an aluminum dihydride complex supported by a simple amido-amine ligand (Chapters 2). Aluminum is the most electropositive element deposited by purely thermal ALD to date and represents a significant breakthrough for this field. This process may have important industrial applications and …


Characterization Of Protonated Modified Nucleosides And Amino Acid-Linked Cisplatin Analogues Using Tandem Mass Spectrometry Complemented By Theoreticical Approaches, Chenchen He Jan 2018

Characterization Of Protonated Modified Nucleosides And Amino Acid-Linked Cisplatin Analogues Using Tandem Mass Spectrometry Complemented By Theoreticical Approaches, Chenchen He

Wayne State University Dissertations

The chemical difference between DNA and RNA nucleosides is their 2′-hydrogen versus 2′-hydroxyl substituents. The 2′-O-methylation is common among natural posttranscriptional modifications of RNA. The structures and relative glycosidic bond stabilities of the protonated forms of the 2′-O-methylated nucleosides, 2′-O-methyladenosine (Adom), 2′-O-methylguanosine (Guom), 2′-O-methycytidine (Cydm), 2′-O-methyluridine (Urdm), and 5,2′-O-dimethyluridine (Thdm) are examined using two complementary tandem mass spectrometry approaches, infrared multiple photon dissociation (IRMPD) action spectroscopy and energy-resolved collision-induced dissociation (ER-CID). Theoretical calculations are also performed to predict the structures and relative stabilities of stable low-energy conformations of the protonated forms of the 2′-O-methylated nucleosides and their infrared spectra in …


Carbohydrate-Based Inducers Of Cellular Stress For Targeting Cancer Cell Metabolism, Fidelis Ndombera Jan 2018

Carbohydrate-Based Inducers Of Cellular Stress For Targeting Cancer Cell Metabolism, Fidelis Ndombera

Wayne State University Dissertations

ABSTRACT

CARBOHYDRATE-BASED INDUCERS OF CELLULAR STRESS FOR TARGETING CANCER CELL METABOLISM

by

FIDELIS TOLOYI NDOMBERA

May 2018

Advisor: Dr. Young-Hoon Ahn

Major: Chemistry (Biochemistry)

Degree: Doctor of Philosophy

Metabolic reprogramming and redox control of cancer cells is vital for their proliferation, but also provides selective strategies for treating cancer. Increased generation of reactive oxygen species (ROS) and an intricate control of redox status in cancer cells relative to normal cells provide a basis for designing ROS-inducing anticancer agents. In my work, I designed, synthesized and evaluated carbohydrate-based small molecules for ROS-generation, cytotoxicity and redox signaling and stress response. Our data …


Tandem Mass Spectrometry And Computational Approaches To Elucidate Conformations And N-Glycosidic Bond Stabilities Of Dna And Rna Nucleosides And Mononucleotides, Yanlong Zhu Jan 2018

Tandem Mass Spectrometry And Computational Approaches To Elucidate Conformations And N-Glycosidic Bond Stabilities Of Dna And Rna Nucleosides And Mononucleotides, Yanlong Zhu

Wayne State University Dissertations

ABSTRACT

TANDEM MASS SPECTROMETRY AND COMPUTATIONAL APPROACHES TO ELUCIDATE CONFORMATIONS AND N-GLYCOSIDIC BOND STABILITIES OF DNA AND RNA NUCLEOSIDES AND MONONUCLEOTIDES

by

YANLONG ZHU

May 2018

Advisor: Dr. Mary T. Rodgers

Major: Analytical Chemistry

Degree: Doctor of Philosophy

The influence of noncovalent interactions with sodium cations on the conformations and energetics of ten DNA and RNA nucleosides as well as two adenine mononucleotides were elucidated via infrared multiple photon dissociation (IRMPD) action spectroscopy experiments and complementary electronic structure calculations. Energy-resolved collision-induced dissociation (ER-CID) experiments of protonated and metal cationized DNA and RNA nucleosides were performed using a Bruker amaZon ETD …


Synthesis Of Open-Chain And Macrocyclic Xanthene-Bridged Bimetallic Cobalt, Nickel, And Copper Complexes For Cooperative Catalysis, Ryan Lance Hollingsworth Jan 2018

Synthesis Of Open-Chain And Macrocyclic Xanthene-Bridged Bimetallic Cobalt, Nickel, And Copper Complexes For Cooperative Catalysis, Ryan Lance Hollingsworth

Wayne State University Dissertations

Within the numerous fields of inorganic chemistry, there is a growing interest to design dinucleating ligands for transition metals. This interest derives from the expansive list of bimetallic and polymetallic centers observed in nature that employ vital small molecules for catalysis, such as carbon dioxide, dinitrogen, and water. Many research groups have attempted to harness that structural and functional metal-metal cooperativity displayed by these enzymes, in hopes of enhancing transition metal catalysis. The overall focus of my dissertation is on utilizing late first-row transition metals, bound to either iminopyridine, bis(imino)pyridine, or bis(2-pyridinylmethyl)amine chelates, tethered by a xanthene linker towards bimetallic …


Harnessing Radical Reactivity For The Construction Of Natural Product Frameworks And Transition Metal Catalyst Stability In A Modified Kochi Coupling Reaction, Mathes Hewage Hansamali Sakuntala Sirinimal Jan 2018

Harnessing Radical Reactivity For The Construction Of Natural Product Frameworks And Transition Metal Catalyst Stability In A Modified Kochi Coupling Reaction, Mathes Hewage Hansamali Sakuntala Sirinimal

Wayne State University Dissertations

Polycyclic N-containing heterocycles play an important role in therapeutic

applications and as molecular tools in studying biological processes, making them

important synthetic targets. Current synthetic approaches are too lengthy, use toxic

reagents or are limited to accessing a particular framework and hence, their synthesis

warrant further study. We have recently developed conditions to avoid both reduction and

slow addition in aminyl radical cyclizations in our venture to access the constrained ABC

core of calyciphilline A, a Daphniphyllum alkaloid. An electron deficient enone with a

pendent internal alkyne as the neutral aminyl radical precursor was used for radical

cyclization. Based on …


Progress Toward Controlled Disulfide Formation To Access Neuroactive Conotoxins, Thilini Kondasinghe Jan 2018

Progress Toward Controlled Disulfide Formation To Access Neuroactive Conotoxins, Thilini Kondasinghe

Wayne State University Dissertations

"Conotoxins are mini proteins isolated from marine snails of the Conus family. They have shown activity in the selective inhibition of various ion channels. Therefore, they present an opportunity as possible therapy for a myriad of neurological ailments. The synthesis of conotoxins would enable both biological studies and evaluation of these structures as lead targets for therapeutics. However, establishing a reliable method to consistently folding disulfide rich proteins, including conotoxin, into their native structure has been challenging over few decades. In this research project, it is shown the progress towards a mild, efficient, and broadly applicable methods to generate the …


Addressing The Threat Of Multidrug Resistant Infectious Diseases By Synthesis Of Novel Aminoglycoside Antibiotics, Girish Chandra Sati Jan 2018

Addressing The Threat Of Multidrug Resistant Infectious Diseases By Synthesis Of Novel Aminoglycoside Antibiotics, Girish Chandra Sati

Wayne State University Dissertations

The ever-growing increase in multidrug resistant infectious diseases is one of the major cause of human mortality, and there is an inherent need for the development of new antibiotics. Since the discovery of streptomycin, AGAs have been playing a very important role in human therapy as highly potent broad-spectrum antibiotics and are listed as one of the critically important antimicrobials by WHO. AGAs act by inhibiting the bacterial protein synthesis and by targeting the A-site present in the small subunit of bacterial ribosome. The clinical use of AGAs is somewhat restricted due to their toxic effects (ototoxicity and nephrotoxicity) and …


Computational Study Of Transition Metal Complexes For Solar Energy Conversion And Molecular Interaction With Strong Laser Fields, Xuetao Shi Jan 2018

Computational Study Of Transition Metal Complexes For Solar Energy Conversion And Molecular Interaction With Strong Laser Fields, Xuetao Shi

Wayne State University Dissertations

There are two topics in this dissertation: ground state and excited state modeling of a few series of transition metal complexes that facilitate solar energy conversion, and Born-Oppenheimer Molecular Dynamics (BOMD) simulations of molecular cations interacting with intense mid-infrared laser light.

In Chapter 2 and 3, a few series of transition metal complexes that facilitate solar energy conversion are studied computationally. Metal-to-ligand charge-transfer (MLCT) excited states of several (ruthenium) (monodentate aromatic ligand, MDA) chromophore complexes are modeled by using time-dependent density function theory (TD-DFT). The calculated MLCT states correlate closely with the heretofore unknown emission properties that were observed experimentally. …


Drug Delivery Strategies For The Treatment Of Advanced Lung Cancer And Various Lung Metastases, Elizabeth Bielski Jan 2018

Drug Delivery Strategies For The Treatment Of Advanced Lung Cancer And Various Lung Metastases, Elizabeth Bielski

Wayne State University Dissertations

Lung cancer remains the leading cause of cancer-related deaths in the United States. Secondary lung tumors metastasized from other cancer sites also remains highly prevalent, in which most metastatic tumors cannot be cured with existing therapies. Chemoresistance (multi drug resistance – MDR) that develops intrinsically or acquired is one of the key factors leading to fatality in these patients. MDR develops form a variety of resistance mechanisms that can occur consecutively or concurrently, therefore, making most current treatments unsuccessful. Current therapies have known to slow tumor growth, but rarely provide a cure. Immunotherapy has seen some promise, including the use …


Uncertainty In Combustion Reaction Rates And Its Effects On Combustion Simulations, Joshua Piehl Jan 2018

Uncertainty In Combustion Reaction Rates And Its Effects On Combustion Simulations, Joshua Piehl

Wayne State University Theses

This work investigates the uncertainties in reaction rates of an n-dodecane model on turbulent spray combustion simulations. Six major reactions were found to significantly impact the ignition delay of the mechanism in a 0-D batch reactor model. These reactions’ rates were independently modified and placed into individual mechanisms. These newly developed mechanisms were simulated in a 3-D turbulent spray simulation and a 0-D batch reactor at a pressure of 60 bar and temperatures from 900 to 1100 K. The combustion characteristics (e.g. ignition delays, flame lift-off length, liquid and vapor penetration) of the modified mechanisms were compared to those produced …


Design, Synthesis, And Reactivity Of Homo- And Heterobimetallic Complexes Bridged By A Xanthene Linker, Thilini Samangi Hollingsworth Jan 2018

Design, Synthesis, And Reactivity Of Homo- And Heterobimetallic Complexes Bridged By A Xanthene Linker, Thilini Samangi Hollingsworth

Wayne State University Dissertations

Cooperative reactivity of bimettalics can be is observed in many different areas of chemistry and have been increasingly investigated because of the advantageous reactivity when compared to the corresponding mononuclear systems. The focus of my dissertation is on (1) investigation of the homobimetallic cooperativity in lactide polymerization catalysis; (2) investigation of the heterobimetallic cooperativity in the biomimetic studies of Mo-Cu carbon monoxide dehydrogenase (CODH) enzyme in order to make a functional model of its active site.

Three new main group bis(alkoxide) complexes Mg(OR)2(THF)2, Zn(Cl)(μ2-OR)2Li(THF) and In(OR)2(μ2-Cl)2Li(THF)2 featuring bulky alkoxide [OCtBu2Ph] were synthesized serve as metal alkoxide precursors for bimetallic lactide …