Chemistry Commons^™

The Advanced Spectroscopic Analysis Of Organic Gunshot Residue And Explosives, Jennifer M. Leonard

Dissertations, Theses, and Capstone Projects

With the prevalence of shooting cases and terrorist attacks/or threats that plague the current state of the criminal justice system, it is of paramount importance to be able to detect, identify and interpret the presence of gunshot residue or explosives material. This concern is seen in law enforcement agencies and the media throughout the United States and abroad.

Currently, the typical method of analyzing gunshot residue in most crime laboratories serves to identify the inorganic constituents of the primer residue, namely lead, barium and antimony. However, it is possible that the organic matter from the propellant could provide different information …

The Modified Stereospecific Stille Reaction: Palladium-Catalyzed Cross-Coupling Reactions Involving Secondary And Tertiary Alkyl Carbastannatranes, Chao-Yuan Wang

Dissertations, Theses, and Capstone Projects

Organic chemistry is present in all domains of everyday life, from polymer production to medicine. In order to synthesize complex compounds, it is often necessary to make new carbon-carbon bonds. Transition metal catalysts, particularly those derived from second and third row metals such as Pt, Pd, Rh, and Ir metals, display remarkable efficiency for the formation of carbon-carbon and carbon-heteroatom bonds. In the first chapter, introduction of transition metal-catalyzed cross-coupling reactions is given. While the formation of C(sp²)–C(sp²) bonds has been studied extensively, C(sp³)-C(sp²) bond formation still presents a challenge due to …

Copalic Acid Analogs Down-Regulate Androgen Receptor And Inhibit Small Chaperone Protein, Nethrie D. Idippily, Qiaoyun Zheng, Chunfang Gan, Aicha Quamine, Morgan M. Ashcraft, Bo Zhong, Bin Su Ph.D.

Chemistry Faculty Publications

Copalic acid, one of the diterpenoid acids in copaiba oil, inhibited the chaperone function of α-crystallin and heat shock protein 27 kD (HSP27). It also showed potent activity in decreasing an HSP27 client protein, androgen receptor (AR), which makes it useful in prostate cancer treatment or prevention. To develop potent drug candidates to decrease the AR level in prostate cancer cells, more copalic acid analogs were synthesized. Using the level of AR as the readout, 15 of the copalic acid analogs were screened and two compounds were much more potent than copalic acid. The compounds also dose-dependently inhibited AR positive …

Conformational Studies Of Gram-Negative Bacterial Quorum Sensing 3-Oxo N-Acyl Homoserine Lactone Molecules, Darren Crowe, Alan Nicholson, Adrienne Fleming, Ed Carey, Goar Sanchez-Sanz, Fintan Kelleher

Articles

In their ¹H NMR spectra in CDCl₃ 3-oxo-N-acyl homoserine lactones (OHLs) show significant downfield chemical shifts of the amide N-H proton when compared to the parent N-acyl homoserine lactones (AHLs). NMR spectroscopic and DFT calculation studies have shown that this is most likely due to the presence of a stabilising intramolecular H-bond from the N-H to the 3-oxo group. The ¹H NMR spectra also show evidence for the enol tautomers and that the amount of enol present for a range of OHLs is 4.1-4.5% in CDCl₃ and 6.5-7.2% in CD₃CN. In …

Climate Change, One Health And Mercury, L. K. Duffy, T. Vertigan, B. Dainowski, K. Dunlap, Amy Hirons

Marine & Environmental Sciences Faculty Articles

Climate change is occurring on both regional and global scales. The use and global distribution of toxic metals is increasing and affecting environmental, animal and human health as a result of air, water and food contamination. Mercury (Hg) in major forms Hg°, Hg²⁺ and methyl mercury (CH₃Hg⁺) are increasingly available around the globe. Both metal and organic contaminants are impacting the health of all species on the planet. Mercury is an example of a metal that can cause or aggravate a disease state, for example, diabetes. Habitat stewardship is needed to maintain a healthy system, …

Structures Of Metallacarboranes And Coordination Complexes: Coordination Sensors Based On Rhodamine B And Quinolines, Agozie Nnaemeka Oyeamalu

Dissertations

Rhodamine-based ligands that can complex different metals has been designed and synthesized. Using Rhodamine B as starting material, we synthesized and characterized quinoline precursors as well as successfully carried out the oxidation of methyl and aldehyde groups on the quinoline ring, and on the hydroxyl moiety of the quinoline spirolactone ring. These turn-on/off rhodamine fluorescence probes sense Cr³⁺ and Ni²⁺ with high selectivity and sensitivity. These probes can be applied to detect other metal ions that are present in chemical, biological and environmental settings. They were designed to fluoresce when bonded to ions such as cyanide in detecting …

Chemotypic Variation Of Biogenic Volatile Organic Compounds In Midwest Forest And Atmospheric Role Of Peroxyacyl Nitrates In Southeastern U.S., Shino Toma

Dissertations

Biogenic volatile organic compounds (VOC), including isoprene and terpenes, impact atmospheric processes such as production of tropospheric ozone, formation and growth of secondary organic aerosol (SOA), global climate change, and human health. Although estimated emission rates of total biogenic VOC exceed anthropogenic emissions, there are many challenges to direct measurements because they are very reactive with atmospheric oxidants and some are still difficult to detect by current analytical techniques. Therefore, high uncertainties lead to discrepancies between individual and total biogenic VOC budget with atmospheric oxidants and an underestimation of SOA formation.

White pine (Pinus strobus) was once a dominant species …

Characterization Of Γ-Butyrolactone Rings: A Computational And Toxicological Study, Donald C. Kidd

Masters Theses

Given the declining state of the natural environment, identifying green methodologies in synthetic chemistry is becoming paramount. An under explored area of green chemistry, is the use of catalytic systems in green solvents. One interesting concept in green chemistry is the use of N-Heterocyclic Carbenes (NHCs) as organocatalysts.

Thiamine or vitamin B1 was one of the first NHCs recognized. Thiamine is required for carbohydrate metabolism and helps the cell produce adenosine triphosphate (ATP). Over the last 20 years NHCs have been found to be efficient catalysts in carbon-carbon bond forming reactions.

But to date, little research has been done exploring …

Novel Spectroscopic Tools To Differentiate Drug-Dna Binding Interactions, Fadwa Dhafer Hamad

Masters Theses

DNA-drug interactions play a major role in therapeutics, diagnostics, forensics and imaging. Drugs bind to DNA in several ways based on the mode of interaction and they alter protein-DNA interactions or breaks/cleaves DNA that can lead to the cure of the disease. The major goal of the research carried out in this thesis is to develop novel optical spectroscopic tools that can differentiate Drug-DNA binding interactions mode whether its intercalation or minor-groove binding. To achieve this goal, we developed two-photon absorption (2PA) cross-section based technique to differentiate between Drug-DNA binding modes. The investigations were carried out on two drug molecules, …

Development Of A Humidity-Resistant Coating To Impart High Oxygen Barrier Performance To Food Packaging Films, Ryan Yinghua Cox

Master's Theses

Oxygen barrier coatings have the potential to greatly extend the lifetime of certain food products by incorporating them into existing food packaging. Present technologies face definite challenges of maintaining high performance, while attaining simple and inexpensive preparation methods. The oxygen barrier effect obtained with these coatings is also susceptible to a plasticization effect when exposed to high humidity, since water vapor molecules are readily soluble in typically hydrophilic resins. In this work, we demonstrate a 1 – 2 micron thick oxygen barrier coating, prepared on a 12 micron poly(ethylene terephthalate) substrate, that has oxygen transmission rates as low as 1.44 …

A Comparison Study Of Two Synthesis Methods For Polymer Of Intrinsic Microporosity 1 (Pim-1), Conor S. Perry

Materials Engineering

Polymers of Intrinsic Microporosity (PIMs) are an emerging polymeric material class for molecular sieving applications. This study focuses on PIM-1, an alternating copolymer of 5,5’,6,6’-tetrahydroxy-3,3’,3,3’-tetramethyl-1,1’-spirobisindane and tetrafluoroterephthalonitrile synthesized via nucleophilic aromatic substitution. PIM-1 been widely studied as a gas separating material and filtering membrane, but in this case, it is studied as a battery separator material. PIM-1’s microporous (pore diameters less than 2 nm) structure allows smaller favorable ions to transport while preventing larger ions and compounds from transporting. Two synthesis methods, round bottom flask synthesis and ball mill synthesis, of PIM-1 are compared to see any improved characteristics. The …

Depletion Of Ozone And Reservoir Species Of Chlorine And Nitrogen Oxide In The Lower Antarctic Polar Vortex Measured From Aircraft, T. Jurkat, C. Voigt, S. Kaufmann, J.-U. Grooß, H. Ziereis, A. Dörnbrack, P. Hoor, H. Bozem, A. Engel, H. Bönisch, P. F. Bernath

Chemistry & Biochemistry Faculty Publications

Novel airborne in situ measurements of inorganic chlorine, nitrogen oxide species, and ozone were performed inside the lower Antarctic polar vortex and at its edge in September 2012. We focus on one flight during the Transport and Composition of the LMS/Earth System Model Validation (TACTS/ESMVal) campaign with the German research aircraft HALO (High-Altitude LOng range research aircraft), reaching latitudes of 65°S and potential temperatures up to 405 K. Using the early winter correlations of reactive trace gases with N₂O from the Atmospheric Chemistry Experiment-Fourier Transform Spectrometer (ACE-FTS), we find high depletion of chlorine reservoir gases up to ∼40% …

Scitech News Volume 71, No. 2 (2017)

Sci-Tech News

Columns and Reports

• From the Editor 3

Division News

• Science-Technology Division 5
• Chemistry Division 8
• Engineering Division 9
• Aerospace Section of the Engineering Division 12
• Architecture, Building Engineering, Construction and Design Section of the Engineering Division 14

Reviews

• Sci-Tech Book News Reviews 16

Advertisements

• IEEE 4

Evaluation Of A Filtration Sorbent For Remediation Of Arsenic In Groundwater, Clement Do

Electronic Theses, Projects, and Dissertations

A commercially available product, PURA PhosLock, was identified and evaluated for use as a sorbent to remove dissolved arsenic (As) from drinking water. Although marketed as a product to remove phosphate in aquaria, it is composed of iron oxide hydroxide (i.e., FeO(OH)), which is also known to adsorb dissolved As species from water. Arsenic was measured using standard methods and Graphite Furnace Atomic Absorption Spectroscopy. A first rough filtration test was performed to see if the PhosLock adsorbed As well. About 50 g of PhosLock was used to filter 10 L of tap water containing 100 ppb As. No detectable …

Crystal Structure Of 4,4′-Bis­­[3-(Piperidin-1-Yl)Prop-1-Yn-1-Yl]-1,1′-Biphen­Yl, Anqi Walbaum, E. Kim Fifer, Sean R. Parkin, Peter A. Crooks

Chemistry Faculty Publications

The title compound, C₂₈H₃₂N₂, (I), is one of a second generation of compounds designed and synthesized based on a very potent and selective α9α10 nicotinic acetyl­choline receptor antagonist ZZ161C {1,1′-[[1,1′-biphen­yl]-4,4′-diylbis(prop-2-yne-3,1-di­yl)]bis­(3,4-di­methyl­pyridin-1-ium) bromide}, which has shown analgesic effects in a chemotherapy-induced neuropathy animal model. Compound (I) was synthesized by the reaction of 4,4′-bis­(3-bromo­prop-1-yn-1-yl)-1,1′-biphenyl with piperidine at room temperature in aceto­nitrile. The single-crystal used for X-ray analysis was obtained by dissolving (I) in a mixture of di­chloro­methane and methanol, followed by slow evaporation of the solvent. In the crystal of (I), the biphenyl moiety has a twisted …

Characterization Of Aquarefined Micro/Nanoporous Lead Material, Liam S. Russell, June Y. Suh

Materials Engineering

The process of aquarefining is an environmentally-friendly method for producing pure lead products that exhibit particularly low density. To observe the microstructures of these low-density forms of lead, scanning electron microscopy (SEM) was employed to examine aquarefined lead samples produced under three batches of processing conditions. Due to aquarefined lead's tendency to collapse under its own weight, careful measures were taken during transport and handling to avoid damaging the samples. Three types of microstructures were observed and correlated to changes in processing conditions: octahedron crystallites, microscales, and dendrites. Energy-dispersive x-ray spectrometry (EDS) was used to quantify the amount of oxygen …

Resolving Three-State Ligand-Binding Mechanisms By Isothermal Titration Calorimetry: A Simulation Study, Evgenii L. Kovrigin

Chemistry Faculty Research and Publications

In this paper, I theoretically analyzed ITC profiles for three-state equilibria involving ligand binding coupled to isomerization or dimerization transitions. Simulations demonstrate that the mechanisms where the free or ligand-bound protein undergoes dimerization (such that the ligand cannot bind to or dissociate from the dimer) produce very distinctive titration profiles. In contrast, profiles of the pre-existing equilibrium or induced-fit models cannot be distinguished from a simple two-state process, requiring data from additional techniques to positively identify these mechanisms.

Industrial Grade 2d Molybdenum Disulphide (Mos2): An In-Vitro Exploration Of The Impact On Cellular Uptake, Cytotoxicity, And Inflammation, Caroline Moore, Hugh Byrne, Jonathan N. Coleman, Yuri Volkov, Jennifer Mcintyre

Articles

The recent surge in graphene research, since its liquid phase monolayer isolation and characterization in 2004, has led to advancements which are accelerating the exploration of alternative 2D materials such as molybdenum disulphide (MoS2), whose unique physico-chemical properties can be exploited in applications ranging from cutting edge electronic devices to nanomedicine. However, to assess any potential impact on human health and the environment, the need to understand the bio-interaction of MoS2 at a cellular and sub-cellular level is critical. Notably, it is important to assess such potential impacts of materials which are produced by large scale production techniques, rather than …

Detection Of Cathinone And Mephedrone In Plasma By Lc-Ms/Ms Using Standard Addition Quantification Technique, Theron W. Ng-A-Qui

Student Theses

Designer drugs are structural analogs of Drug Enforcement Agency (DEA) Schedule I and II substances. They are synthesized to mimic the effects of illegal drugs of abuse and to bypass the provisions of drug regulations. Despite the increased availability of designer drugs, few studies have focused on specific analytical extraction techniques for their detection and quantification in biological samples. Solid phase extraction (SPE) is the most commonly used technique for sample preparation. The purpose of this study is to evaluate the extraction efficiency of the various SPE columns with different sorbent materials for two designer drugs, cathinone and mephedrone in …

An Investigation Of Chemical Identity Thinking, Courtney L. Ngai

Graduate Doctoral Dissertations

Chemical identity is a foundational crosscutting concept in chemistry and encompasses the knowledge, reasoning, and practices relevant for the classification and differentiation of substances. Substances are found everywhere – from the chemistry classroom to the kitchen at home – so classification and differentiation of substances is important for everyday decisions as well as challenges that are solved using chemistry. An understanding of chemical identity, then, is essential for scientifically literate citizens in addition to students training to be chemists. A better understanding of how chemical identity thinking develops could be used to inform instruction and education research, with the intent …

Serendipitous Discovery Of Light-Induced (In Situ) Formation Of An Azo-Bridged Dimeric Sulfonated Naphthol As A Potent Ptp1b Inhibito, Robert D. Bongard, Michael Lepley, Khushabu Thakur, Marat R. Talipov, Jaladhi Nayak, Rachel A. Jones Lipinski, Chris Bohl, Noreena Sweeney, Ramani Ramchandran, Rajendra Rathore, Daniel S. Sem

Chemistry Faculty Research and Publications

Background

Protein tyrosine phosphatases (PTPs) like dual specificity phosphatase 5 (DUSP5) and protein tyrosine phosphatase 1B (PTP1B) are drug targets for diseases that include cancer, diabetes, and vascular disorders such as hemangiomas. The PTPs are also known to be notoriously difficult targets for designing inihibitors [sic] that become viable drug leads. Therefore, the pipeline for approved drugs in this class is minimal. Furthermore, drug screening for targets like PTPs often produce false positive and false negative results.

Results

Studies presented herein provide important insights into: (a) how to detect such artifacts, (b) the importance of compound re-synthesis and verification, and …

Datasets On The Genomic Positions Of The Mll1 Morphemes, The Zfp57 Binding Site, And Zfbs-Morph Overlaps In The Build Mm9 Of The Mouse Genome, Minou Bina, Phillip Wyss, Xiaohui C. Song

Department of Chemistry Faculty Publications

While MLL1 activates gene expression in most tissues, ZFP57 represses transcription. MLL1 selectively interacts with a group of nonmethylated DNA sequences known as the MLL1 morphemes. ZFP57 associates with a methylated hexamer (ZFBS), dispersed in the genomic DNA segments known as Imprinted Control Regions (ICRs) and germline Differentially Methylated Regions (gDMRs), to maintain allele-specific gene repression. We have identified a set of composite DNA elements (ZFBS-Morph overlaps) that provides the sequence context of ZFBS in the canonical ICRs/gDMRs. This report provides tables listing the nucleotide sequences of the MLL1 morphemes and ZFBS-Morph overlaps. The report also offers links to the …

The Investigation And Characterization Of The Reaction Of 2-Methylfuran And 2-Methyl-3-Buten-2-Ol With O(3p) And The Photodissociation Of Xylyl Bromide Isomers, Yasmin Fathi

Master's Theses

This thesis has studied the oxidation behavior of different biofuels or additives, 2-methyl-3-buten-2-ol and 2-methylfuran, in combustion experiments at the Chemical Dynamics Beamline held at the Advanced Light Source of the Lawrence Berkley National Laboratory. The oxidation of these fuels were initiated through O(³P) and the combustion experiments were analyzed using a multiplexed chemical kinetics photoionization mass spectrometer with tunable synchrotron radiation. Products of the different reactions were identified using kinetic profiles and further characterized using the photoionization spectra. The amount of each species was calculated using branching fractions.

Additionally, the unimolecular dissociation of the xylyl bromide isomers …

Crystal Structure Of {N-[(6-Bromopyridin-2-Yl)- (Phenyl)Methylidene]-2,6-Dimethylaniline-Κ²N,N'}- Dichloridozinc Dichloromethane Hemisolvate, Bradley M. Wile

Chemistry and Biochemistry Faculty Scholarship

The solvated title compound, [ZnCl₂(C₂₀H₁₇BrN₂)]·0.5CH₂Cl₂, comprises a bidentate imino­pyridine ligand and two Cl atoms bound to a zinc²⁺ cation in a distorted tetra­hedral arrangement. The chelate bond lengths are consistent with localized C=N double bonds and a C—C single bond, as expected for an unreduced ligand bound to a closed-shell transition metal cation. Apart from weak nonclassical C—HCl hydrogen bonds between the complex mol­ecules and the disordered solvent mol­ecules (occupancy = 0.5), no further significant inter­molecular inter­actions are observed.

Rapid Reversible Borane To Boryl Hydride Exchange By Metal Shuttling On The Carborane Cluster Surface, Bennett J. Eleazer, Mark D. Smith, Alexey A. Popov, Dmitry V. Peryshkov

Faculty Publications

In this work, we introduce a novel concept of a borane group vicinal to a metal boryl bond acting as a supporting hemilabile ligand in exohedrally metalated three-dimensional carborane clusters. The (POBOP)Ru(Cl)(PPh3) pincer complex (POBOP ¼ 1,7-OP(i-Pr)2-m-2-carboranyl) features extreme distortion of the two-center-two-electron Ru–B bond due to the presence of a strong three-centertwo-electron B–H/Ru vicinal interaction. Replacement of the chloride ligand with a hydride afforded the (POBOP)Ru(H)(PPh3) pincer complex, which possesses B–Ru, B–H/Ru, and Ru–H bonds. This complex was found to exhibit a rapid exchange between hydrogen atoms of the borane and the terminal hydride through metal center shuttling between …

Application Of Bottlebrush Block Copolymers As Photonic Crystals, Allegra L. Liberman-Martin, Crystal K. Chu, Robert H. Grubbs

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Brush block copolymers are a class of comb polymers that feature polymeric side chains densely grafted to a linear backbone. These polymers display interesting properties due to their dense functionality, low entanglement, and ability to rapidly self-assemble to highly ordered nanostructures. The ability to prepare brush polymers with precise structures has been enabled by advancements in controlled polymerization techniques. This Feature Article highlights the development of brush block copolymers as photonic crystals that can reflect visible to near-infrared wavelengths of light. Fabrication of these materials relies on polymer self-assembly processes to achieve nanoscale ordering, which allows for the rapid preparation …

Stereochemical Preference Toward Oncotarget: Design Synthesis And In Vitro Anticancer Evaluation Of Diastereomeric B-Lactams, Fabian Olazarán-Santibáñez, Debasish Bandyopadhyay, Pilar Carranza-Rosales, Gildardo Rivera, Isias Balderas-Rentería

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

Purpose: In the battle against cancer discovery of new and novel chemotherapeutic agent demands extreme obligation. Development of anticancer compounds with higher potency and reduced side-effects is timely and challenging.

Experimental Design: A small series of fourteen diastereomeric β-lactams (seven pairs) were synthesized through multi-step process exploring [2+2] ketene-imine cycloaddition as the key step. Comparative stereochemical preferences were studied through computational docking and validated by in vitro evaluation. β-tubulin was considered as possible molecular target and in vitro anticancer evaluation was conducted against SiHa, B16F10, K562 and Chang cell lines. Caspase-3 activation assay and hematoxylin/eosin staining of the cells were …

Preferential Binding Effects On Protein Structure And Dynamics Revealed By Coarse-Grained Monte Carlo Simulation, Ras B. Pandey, D.L. Jacobs, Barry L. Farmer

Faculty Publications

The effect of preferential binding of solute molecules within an aqueous solution on the structure and dynamics of the histone H3.1 protein is examined by a coarse-grained Monte Carlo simulation. The knowledge-based residue-residue and hydropathy-index-based residue-solvent interactions are used as input to analyze a number of local and global physical quantities as a function of the residue-solvent interaction strength (f). Results from simulations that treat the aqueous solution as a homogeneous effective solvent medium are compared to when positional fluctuations of the solute molecules are explicitly considered. While the radius of gyration (R_g) of the …

Microwave-Assisted Topochemical Manipulation Of Layered Oxide Perovskites: From Inorganic Layered Oxides To Inorganic-Organic Hybrid Perovskites And Functionalized Metal-Oxide Nanosheets, Sara Akbarian-Tefaghi

LSU New Orleans Theses and Dissertations

Developing new materials with desired properties is a vital component of emerging technologies. Functional hybrid compounds make an important class of advanced materials that let us synergistically utilize the key features of the organic and inorganic counterparts in a single composite, providing a very strong tool to develop new materials with ”engineered” properties. The research presented here, summarizes efforts in the development of facile and efficient methods for the fabrication of three- and two-dimensional inorganic-organic hybrids based on layered oxide perovskites. Microwave radiation was exploited to rapidly fabricate and modify new and known materials. Despite the extensive utilization of microwaves …

Design, Synthesis And Glioblastoma Activity Of 1,3-Diazinane Based Aryl Amides And Benzo Fused Heterocycles, Rebecca Hron

LSU New Orleans Theses and Dissertations

The development of novel targeted therapeutics for the treatment of cancer remains difficult due to the complex nature of the disease itself as well as the challenges associated with the synthesis of these therapeutics. Impediments to the discovery of novel drug candidates include lack of available starting materials and access to well-developed syntheses which are both convenient and economically feasible. Semicarbazides, for instance, are a critical synthon for the manufacture of numerous biologically important molecules. Historically, convenient methods for the synthesis of semicarbazides and their derivatives did not exist. Recently, a facile and efficient method for the preparation of semicarbazides …