Physical Sciences and Mathematics Commons^™

A Simplified Direct Lipid Mixing Lipoplex Preparation: Comparison Of Liposomal-, Dimethylsulfoxide-, And Ethanol-Based Methods, Joseph Meisel, George Gokel

Chemistry & Biochemistry Faculty Works

Established transfection methodology often uses commercial reagents, which must be formed into liposomes in a sequence of about half a dozen steps. The simplified method reported here is a direct lipid mixing approach that requires fewer steps, less manipulation, and is less time-consuming. Results are comparable to those obtained with more commonly used methods, as judged by a variety of analytical techniques and by comparisons of transfection results. The method reported here may be applied to non-liposome-forming compounds, thereby greatly expanding the range of structures that can be tested for transfection ability.

A Comparison Of Solvent And Water-Borne Alkyd Coatings And The History Of Voc Regulations In The United States, Molly Elise Burns

Master's Theses

A Comparison of Solvent and Water-Borne Alkyd Coatings Abstract

Conventional solvent based alkyd coatings have gone out of favor due to concerns over volatile organic compound (VOC) content. However, due to recent focus on renewable raw materials, alkyds are making a comeback in waterborne form. Water based alkyd coatings are known to have poor shelf stability and corrosion resistance, as well as other problems during the formulation process. This project focused on comparing solvent borne to two types of water-borne alkyds, water reducible alkyds and alkyds emulsions. The purpose was to understand the differences between the three types of alkyds …

A Simplified Direct Lipid Mixing Lipoplex Preparation: Comparison Of Liposomal-, Dimethylsulfoxide-, And Ethanol-Based Methods, Joseph W. Meisel, George W. Gokel

George Gokel

Photo-Isomerizable Self-Complementary Hydrogen Bond Arrays, Iamnica Janic Linares Mendez

Electronic Thesis and Dissertation Repository

This thesis exploits the use of a photochromic system in a self-complementary hydrogen bond array; i.e. the azo group, -N=N. The novelty of the approach described in this thesis resides in the double function of the azo group within the array: as a hydrogen bond acceptor site and as an element that promotes a structural change capable of disrupting the complexation equilibrium when irradiated with light.

The photo-isomerizable self-complementary hydrogen bond arrays presented are obtained by a general and practical synthetic method from inexpensive starting materials. Their self-complementary recognition was corroborated by ¹H NMR dilution experiments and single crystal …

Synthetic Studies Toward A Novel Hydroxylamine Of Potential Utility In The Preparation Of Mitochondriotropic Nitrones, Gloria Patricia Perez

FIU Electronic Theses and Dissertations

Mitochondrial dysfunction and oxidative stress have been linked with many pathological conditions. Studies suggest that antioxidants able to accumulate in the inner regions of the mitochondria as well as possessing the chemical entities to cross membranes such as the blood brain barrier, could potentially overcome many of the limitations found with current antioxidants.

Nitrones have demonstrated great antioxidant potential due to their free radical scavenging properties, cardio and neuro-protective activities. In this research, several synthetic studies were performed with the aim of synthesizing a novel hydroxylamine of potential utility for the preparation of mitochondria targeted nitrones. These studies resulted in …

Cobalt Mediated Oxidative Cyclizations: The Diastereoselective Synthesis Of Trans-Tetrahydrofuran Rings, Cory D.N. Palmer

Electronic Thesis and Dissertation Repository

The Mukaiyama oxidative cyclization has been a major area of study within the Pagenkopf group and within the field of THF containing natural products. This document contains a brief discussion of the major divisions of THF synthesis; S_N2, cycloadditions, and transition mediated strategies. The development of the Mukaiyama cyclization is described from the earliest applications of cobalt acac type ligand in Mukaiyama’s work to the initial discovery of the cyclization reactivity. Initial finding from the Mukaiyama group is shown, accompanied by its applications to the synthesis of mucosin, aplysiallene, and bullatacin. Previous attempts at improved catalyst design are …

New Chemistry Of Donor-Acceptor Cycloalkanes And Studies Towards The Synthesis Of Streptorubin B, Naresh Vemula

Electronic Thesis and Dissertation Repository

This dissertation presents two separate chapters within the broad area of synthetic organic chemistry. The first chapter describes the annelation chemistry of donor-acceptor (DA) cyclopropanes and cyclobutanes for the synthesis of heterocycles. The Yb(OTf)₃-catalyzed [4+2] cycloaddition between DA cyclobutanes and nitrosoarenes facilitated the synthesis of tetrahydro-1,2-oxazines in good to excellent yields as single diastereomers. Additionally, an unexpected deoxygenation occurred with electron-rich nitrosoarenes under MgI₂-catalysis that afforded pyrrolidine products. The GaCl₃-catalyzed [4+2] cycloaddition of DA cyclobutanes and cis-diazenes provided hexahydropyridazine derivatives in good to excellent yields as single diastereomers. Furthermore, a procedure to make …

Calculating The Energy Barriers Required To Join Metal-Organic Framework Synthesis Intermediates With Non-Equilibrium Molecular Simulation, Marcus A. Tubbs, David Cantu, Roger Rousseau, Vassiliki-Alexandra Glezakou

STAR Program Research Presentations

Metal organic frameworks are synthetic porous materials with great capacity for adsorption of carbon dioxide and methane. They chemically appear as a chain-link fence with nodes of metal connected by organic linkers. The pores between the nodes define the characteristics of the material, allowing gas particles of specific size to pass through while blocking larger particulates. While there has been success in synthesizing small amounts of metal organic frameworks, the mechanistic details behind their assembly remain unknown. Understanding the synthesis mechanism is necessary to understand the kinetics involved and be able to produce this useful material on an industrial scale. …

Synthetic Studies Of Heparan Derivatives: Glycosyl Couplings And Post-Glycosylative Modifications, Hari Raj Khatri

Open Access Dissertations

Heparan sulfate (HS) and closely related heparin are comprised of alternating units of D-glucosamine and either D-glucuronic acid (D-GluA) or L-iduronic acid (L-IdoA), and support variable degrees of sulfation which can interact with a large number of proteins with diverse biological functions. HS oligosaccharides can be constructed from readily accessible D-GlcN and D-GlcA derivatives, but the inclusion of L-IdoA is less straightforward. To address this, our laboratory has developed alternative synthetic strategies for HS-like oligosaccharides to incorporate either D-GlcA or L-IdoA in a synthetically efficient manner by nucleophilic ring opening of 4-epoxypyranosides, which can be made from readily available D-hexoses …

Correlation Of Polymer Performance And Hansen Solubility Parameters, Daniel Jobse Mania

Master's Theses

Ready-to-use (RTU) grout is becoming more important to the finish and remodeling construction industry. Market research shows it is a fast-growing product that not only is creating its own space, but is beginning to supplant existing technology.

The original intent of this research was to investigate formulation parameters and how they affect grout performance. It was learned that particle size and oil absorption (OA) value are important filler properties that affect performance as much as adequate packing density and optimal pigment volume concentration (PVC) without going beyond critical PVC (CPVC).

Polymer architecture was also determined to be extremely important, but …

Selective Iodination Using Diaryliodonium Salts, William H. Miller Iv

Department of Chemistry: Dissertations, Theses, and Student Research

Aryl iodides have become widely recognized as versatile synthetic intermediates, owing to aromatic iodine’s excellent ability to participate in oxidative addition reactions. Iodoarenes readily undergo a variety of synthetic transformations including metal catalyzed cross-coupling reactions, diaryliodonium chemistry, formation of organometallics through reduction or metal-halogen exchange, as well as classical S_N2 type chemistry. Because a wide array of transformations are available for aryl iodides, organic molecules containing this moiety often serve as vital precursors to highly desirable pharmaceuticals.

This thesis describes a simple and selective two-step approach to the formation of aryl iodides. This method proceeds through an easily …

Investigation Of The Interaction Of Dimeric Ruthenium Complexes With Cytochrome B5, Christopher Dain Rupar

Graduate Theses and Dissertations

Photoreactive complexes to study the kinetics of electron transfer of proteins have been in use for a long time. It has always been speculated that complexes bind near the heme or the electron transfer reaction would not occur. But it is unkown exactly how the complex interacts with the protein. The structural, thermodynamic, and kinetic properties of rat liver microsomal cytochrome b5 were investigated when bound to ruthenium dimer complexes. Heteronuclear Single Quantum Coherence studies support a dynamic binding model of a dimer Ru complex bound near the protein’s heme involving residues H39, E44, G42, V61, G62, and H63. The …

Studies In The Asymmetric Synthesis Of The C21-C34 Fragment Of The Natural Product, Antascomicin B, Brian Lee Walker

Graduate Theses and Dissertations

This dissertation describes studies in the asymmetric synthesis of the C21 – C34 fragment of the natural product, antascomicin B. Antascomicin B is structurally related to FK506, binds strongly to FKBP12, yet does not shown immunosuppressive activity. Small ligand FKBP12 binding complexes were shown to have potent neuroprotective and neuroregenerative properties in mouse models of Parkinson’s disease. The highlighted chemical reactions include an asymmetric transfer hydrogenation (ATH), Ireland-Claisen rearrangement (ICR), directed hydrogenation and allylic diazene rearrangement.

Antibacterial Activities Of Wasabi Against Escherichia Coli O157:H7 And Staphylococcus Aureus, Zhongjing Lu, Christopher Dockery, Michael Crosby, Katherine Chavarria, Brett Patterson, Matthew Giedd

Faculty and Research Publications

Escherichia coli O157:H7 and Staphylococcus aureus are two of the major pathogens frequently involved in foodborne outbreaks. Control of these pathogens in foods is essential to food safety. It is of great interest in the use of natural antimicrobial compounds present in edible plants to control foodborne pathogens as consumers prefer more natural “green” foods. Allyl isothiocyanate (AITC) is an antimicrobial compound naturally present in wasabi (Japanese horseradish) and several other edible plants. Although the antibacterial effects of pure AITC and wasabi extract (essential oil) against several bacteria have been reported, the antibacterial property of natural wasabi has not been …

Countercurrent Chromatography Fractions Of Plant Extracts With Anti-Tuberculosis Activity, Douglas Armstrong, Nathan C. Krause, Drew Frey, J. Brent Friesen, Baojie Wan, Jordan Gunn, Scott Franzblau

Faculty Scholarship – Chemistry

Samples of numerous plant species were received from the southwestern part of the USA, from Richard Spjut, and plant samples were collected here in Illinois. All were extracted with typical solvents, giving crude residues, some of which were subjected to chromatographic methods. Some of the crude residues and some of the fractions were tested for anti-tuberculosis activity and/or antibacterial activity.

In a general way, bioactive natural products are dealt with very well by Liang & Fang. More specifically, the southwestern part of the United States has a large variety of indigenous plants many of which have not been investigated for …

Synthesis Of Subtype Selective Bz/Gabaa Receptor Ligands For The Treatment Of Anxiety, Epilepsy And Neuropathic Pain, As Well As Schizophrenia And Asthma, Michael M. Poe

Theses and Dissertations

The α2/α3 subtype selective Bz/GABAA receptor positive allosteric modulator HZ-166 (3) has been shown to be a nonsedating anxiolytic with anticonvulsant and antihyperalgesic activity. However, instability in vitro and in vivo has hindered its advancement into clinical trials. A series of ligands based off HZ-166 (3) were synthesized. Many of these ligands were designed to increase metabolic stability, while others were synthesized to study the effects that electronics and sterics have on the efficacy exerted when bound to the GABAA receptor. The α3 subtype selective methyl ester MP-III-024 (19) was shown to have increased resistance to metabolism in in vitro …

Mechanism Of Rapid Electron Transfer Reactions Involving Cytochrome Bc1, Cytochrome C And Cytochrome Oxidase, Jeremy Erik Durchman

Graduate Theses and Dissertations

Electron transfer between mitochondrial proteins complexes represents the primary means by which living things acquire the requisite energy for survival. The coupling of electron transfer to proton translocation creates an electrochemical gradient that drives the synthesis of highly energetic compounds such as ATP. The purpose of these studies is to measure rates of electron transfer and elucidate the important governing factors in the redox events involving cytochrome bc1, cytochrome c and cytochrome oxidase. Using rapid initiation of redox events triggered by laser flash excitation of ruthenium compounds, and strategically monitoring unique spectral properties of these proteins in the visible region …

Two Studies: Stereoselective C-C Bond Formations Of N-Boc-Piperidines Using Selected Organolithiums And Visible-Light-Mediated Synthesis Of Fused Indolines Using Tethered Styrenes, Scott Alan Morris

Graduate Theses and Dissertations

Chemists worldwide have accepted the challenge of developing methods to access a variety of compounds as single enantiomers, including the use of enzymes, chiral auxiliaries, and resolutions. In particular, dynamic resolutions offer a unique way to access chiral compounds using a few controllable steps, including the variation of both time and temperature. Many groups have implemented this methodology to generate various polysubstituted pyrrolidines and piperidines, which are substructures ranking high on the list of nitrogen–containing pharmaceuticals.

The Gawley group revealed a catalytic dynamic resolution (CDR) of N–Boc–piperidine using a chiral ligand. Impressively, the chemistry was tolerant of a variety of …

[3+2] Annulation Of Cyclopropylanilines With Alkynes Under Photocatalysis, Theresa Ha Nguyen

Graduate Theses and Dissertations

Over the past decade, pharmaceutical industries have prioritized their focus on discovering new innovative drugs, yet the syntheses are often either inefficient or the approach of environmental sustainability presents a great deal of concern. Moreover, the methodology developments for amine syntheses have continued to flourish due to their important role and wide use in pharmaceutics. Yet their syntheses often lack sustainability and efficiency. Synthetic chemists have continued to explore potential innovative avenues for conducting chemical reactions more effectively and efficiently. One of the most abundant, renewable natural resources is solar energy and to harvest, use, and store it directly is …

The Large-Scale Synthesis And Asymmetric Hydrosilylations Of Cuiphet, A C2-Symmetric N-Heterocyclic Carbene, Elizabeth Suzanne Spahn

Graduate Theses and Dissertations

CuIPhEt is a C2-symmetric N-heterocyclic carbene catalyst used in the asymmetric hydrosilylation of a variety of prochiral ketones with good yields and selectivities. The large-scale, five-step synthesis of this carbene has been devised. The second step of the synthetic plan includes a double asymmetric hydrogenation of a 1,1-diaryl alkene—a traditionally difficult transformation. The procedure for the use of CuIPhEt in asymmetric hydrosilylations has been optimized and used on both the originally published substrate scope and new compounds. This protocol for the hydrosilylation has been applied in a 10 g reduction to create an intermediate for use toward the total synthesis …

Silver-Polymer Nanocomposites, Anita N. Paul

Electronic Theses and Dissertations

The objective of this research was the development of an efficient method for the preparation of silver-polymer nanocomposites containing finely dispersed silver nanoparticles. The surface of nanosilver was functionalized by thiolation with 2-aminoethanethiol. Amino-modified nanosilver was covalently bonded to polyacrylic acid, biodegradable polymers like acid terminated polylactic acid, ester terminated poly(DL-lactide-co-glycolide) and acid terminated poly(DL lactide-co-glycolide) in the presence of diisopropylcarbodiimide by carbodiimide method. Esterification of the carboxyl groups of Ag-polyacrylic acid by hydrochloric acid in methanol resulted in the formation of a stable colloidal dispersion of Ag nanoparticles in the polymer matrix. It was observed that not just acid …

The Synthesis Of Chemosensors For Toxic Analytes, Johnathan Hugh Broome

Dissertations

A number of chemosensors have been designed and synthesized to target cations (Zn²⁺ions), neutral molecules (cathinones), charged molecules (aminoindanes), and anions. The Zn²⁺ ion sensor featured bistriazole designed binding unit and ferrocene signaling units. Characterization of Zn²⁺ ion binding was carried out with electrochemical techniques (CV and DPV), ¹H-NMR, mass spectrometry, and molecular modelling. It exhibited a 1:1 binding stoichiometry with Zn²⁺ and had an affinity for ZnCl₂ (Log K_1:1 = 4.1 ± 0.02) over other Zn²⁺ salts.

The cathinone probe was designed to selectively bind mephedrone over common street drugs …

Extraction, Purification And Characterization Of An Antibiotic-Like Compound Produced By Rhodococcus Sp. Mtm3w5.2, Pushpavathi Reddyvari Manikindi

Electronic Theses and Dissertations

The bacterium Rhodococcus is a potential source for novel antimicrobial metabolites. Recently, the Rhodococcus strain MTM3W5.2 was isolated from a soil sample collected from Morristown, East Tennessee and was found to produce an inhibitor molecule that is active against similar Rhodococcus species. The aim of this research is to extract, purify, and characterize the active compound. The compound was obtained from both agar and broth cultures of strain MTM3W5.2 and purified by primary fractionation of crude extract on a Sephadex LH-20 column, followed by semi-preparative reversed phase column chromatography. Final purification was achieved using multiple rounds of an analytical C …

Mida Boronates Are Hydrolysed Fast And Slow By Two Different Mechanisms, Jorge A. Gonzalez, O. Maduka Ogba, Gregory F. Morehouse, Nicholas Rosson, Kendall N. Houk, Andrew G. Leach, Paul H.-Y. Cheong, Martin D. Burke, Guy C. Lloyd-Jones

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

MIDA boronates (N-methylimidodiacetic boronic acid esters) serve as an increasingly general platform for building-block-based small molecule construction, largely due to the dramatic and general rate differences with which they are hydrolysed under various basic conditions. Yet the mechanistic underpinnings of these rate differences have remained unclear, hindering efforts to address current limitations of this chemistry. Here we show that there are two distinct mechanisms for this hydrolysis: one is base-mediated and the other neutral. The former can proceed more than three orders of magnitude faster, and involves rate-limiting attack at a MIDA carbonyl carbon by hydroxide. The alternative ‘neutral’ hydrolysis …

A New Science, And A New Profession: Sugar Chemistry In Louisiana, 1885-1895, John Alfred Heitmann

John A. Heitmann

Between 1885 and 1895 the Louisiana sugar industry experienced a scientific and technological revolution in methods, process apparatus, and scale of operations. The animal-powered mills and open kettles characteristic of the antebellum period were supplanted by large, technically designed, and scientifically controlled central factories . In 1880 there were approximately 1,000 sugar houses in Louisiana with an average annual production of 110 long tons of sugar per house. By 1900 fewer than 300 factories constituted the state's sugar industry, but yearly production averaged over 980 long tons for each sugar house. One commentator of the period, Mark Twain, described a …

Photolysis Of Triazenylbenzoic Acids For Click Chemistry, Adam Gann

Doctoral Dissertations

Copper catalyzed cycloaddition of terminal alkynes and azides has revolutionized the field of bioconjugate chemistry. Unfortunately, typical copper catalysts are known to disrupt relevant biological systems, so it has become necessary to develop new, copper-free methods that are less cytotoxic. particular interest are "click" probes which can be activated with an outside light source, giving the user spatial and temporal control over the system being investigated. We have developed a method in which an aryl diazonium salt is rapidly generated using photolysis of the triazene functional group, and subsequently coupled with an electron rich aromatic nucleophile to yield an azobenzene. …

Design, Synthesis, And Applications Of Nano-Assemblies Based On Amphiphilic Macromolecules, Hui Wang

Doctoral Dissertations

Recent progress in nanotechnology has been significantly impacting a variety of areas such as utilization in microelectronics, multiphase catalysis, sensing and therapeutics. Our interests are to develop new nanomaterials to understand their structure-property relationships and to utilize them for various applications. In this thesis, we discuss our findings on the design, synthesis and applications of nanomaterials formed by self-assembly of amphiphilic molecules. Micelles are self-assembled nanostructures formed by amphiphilic molecules. They are capable of sequestering hydrophobic guest molecules in an aqueous environment. Other than surfactants, micelles can also be formed by amphiphilic polymers or dendrimers, which are macromolecular surfactants in …

Synthesis Of A Small Molecule Nitrosocysteine Inhibitor To Reduce The Activity Of Caspase-1, Catherine A. Shamblen, Caitlin E. Karver

DePaul Discoveries

Caspase-1 is an enzyme that is overactive in autoimmune and autoinflammatory diseases cleaving pro-interleukin-1β to the cytokine interleukin-1β (IL-1β), which leads to inflammatory symptoms. The inhibition of caspase-1 will cause a decrease in the concentration of interleukin-1β (IL-1β), resulting in the reduction of inflammatory symptoms. Recent research has revealed that the appending of a nitric oxide (NO) or nitroxyl (HNO) donating group to non-steroidal anti-inflammatory drugs (NSAIDs) reduced, or avoided, the side effects caused by currently available treatments. A small molecule based on a known caspase-1 inhibitor with a nitrosocysteine appended on was synthesized to look at the effect of …

Serendipitous Discovery Of A New Method For The Catalytic Synthesis Of Indole-Fused Benzazepanes, Edward Gluzman, Paul A. Vadola

DePaul Discoveries

We report here on our investigations into the application of 1,5-hydride transfer cyclization mechanisms to the synthesis of 2,3-disubstituted benzofurans and indoles. We found that PtI₄ in MeCN at 120 ºC was indeed capable of activating the alkyne, however, the expected 2,3-disubstituted indole product was not observed. Instead we isolated an indolyl-3-benzazepane via an unexpected intramolecular Steven’s rearrangement/ring expansion. While this transformation has been previously reported our method may prove to have increased substrate scope and more practical reaction conditions. Further studies are underway to optimize the reaction conditions and to fully explore the scope and mechanism of the …

Insight Into The Inhibition Of Ribonucleotide Reductases By 2'-Chloro-2'-Deoxynucleotides And 2'-Azido-2'-Deoxynucleotides: Biomimetic Studies With Model Substrates, Mukesh M. Mudgal Dr.

FIU Electronic Theses and Dissertations

Ribonucleotide Reductases (RNRs) are crucial enzymes that catalyze reduction of ribonucleotides to deoxyribonucleotides, required for the biosynthesis of DNA. Vital role played by RNR in the biosynthesis of DNA and its control on cell growth made it one of the main targets for anticancer therapy. Several laboratories clarified the aspects of reaction cascades at active site of RNR. Biochemical studies of RNR by Stubbe for the inactivation of RDPR by 2'-chloro-2'-deoxyuridine-5'-diphosphate emphasizes departure of chlorine as an anion, while biomimetic studies by Robins with 6'-O-nitro-2'-chloro-homonucleosides emphasizes the elimination of chlorine substituent from 2'-position as a radical. To clarify …