Chemistry Commons^™

New Catalytic Reactions In Carbohydrate Chemistry, Scott Geringer

Dissertations

Carbohydrates or sugars are some of the most diverse and abundant biological molecules. They are involved in a multitude of processes in the body such as fertilization, cell-cell communication, and cancer metathesis. Because of these vital functions, the study of sugars is rapidly growing field. The field however is limited due to the complex nature of sugars which results in difficulties in obtaining large quantities for study.

Protecting group manipulation is a large emphasis area in carbohydrate chemistry due to the need to selectively protect different functional groups of each molecule during synthesis. Catalytic and selective cleavage of protecting groups …

Universality Of Physical And Chemical Critical Effects In Liquid Mixture, Joshua Lang, Xingjian Wang, Pauline Norris

Research Horizons Day Posters

No abstract provided.

Gram-Scale Synthesis Of 2,5-Difluoro-7,7,8,8-Tetracyanoquinodimethane (F2-Tcnq), En Chih Liu, Joseph J. Topczewski

Chemistry Faculty Research & Creative Works

The molecule 2,5-difluoro-7,7,8,8-tetracyanoquinodimethane (F2-TCNQ) is an organic semiconductor with many promising properties, including high charge mobility (μ). However, an efficient gram-scale synthesis of F2-TCNQ has not been fully documented. Herein, we report a synthesis of F2-TCNQ via a three-step sequence that affords F2-TCNQ in 58% cumulative yield. This synthesis was used to prepare more than 1 g of F2-TCNQ.

Synthesis And Styrene Copolymerization Of Chloro And Fluoro Ring-Substituted Isopropyl 2-Cyano-3-Phenyl-2-Propenoates, Alessandra Cimino

College of Science and Health Theses and Dissertations

Novel trisubstituted ethylenes (TSE), chloro and fluoro 2-cyano-3-phenyl-2-propenoic propenoates (XPhCH=C(CN)CO₂CH(CH₃)₂) were prepared and copolymerized with styrene (ST). The monomers were synthesized by modified crossed aldol condensation reaction (Knoevenagel condensation) of chloro and fluoro ring-substituted benzaldehydes with isopropyl cyanoacetate using piperidine as catalyst. They were subsequently characterized by IR, ¹H and ¹³C-NMR and CHN analysis as well. The novel TSE monomers formed were then copolymerized with styrene (ST) in solution at 70 °C and 1,1′-Azobis(cyclohexanecarbonitrile) (ABCN) was used as radical initiator of the reaction. The composition of the novel copolymers was calculated from …

Analyzing The Retention Of Knowledge Among General Chemistry Students, James T. Kingsepp

USF Tampa Graduate Theses and Dissertations

General chemistry is a survey course meant to form a foundation for students’ to build upon as they progress into chemistry sub-disciplines. The effectiveness of this foundation rests heavily on students’ abilities to retain or relearn concepts from the course. This study seeks to investigate the utility of a measure of general chemistry students’ knowledge retention across the time period of one semester. This approach was enacted in five different courses of either first or second semester general chemistry. The results showed that one-quarter to one-half of students exhibited a high rate of retention across the semester. A smaller group, …

Modified Synthesis Of The Peptidomimetic Natriuretic Peptide Receptor-C Antagonist M372049, Jacob Porter, Sergey V. Lindeman, Chris Dockendorff

Chemistry Faculty Research and Publications

The Natriuretic Peptide Receptors (NPRs) regulate vascular sodium levels and have been of significant interest for the potential treatment of hypertension and related cardiovascular complications. The peptidomimetic antagonist M372049 is a valuable probe for the study of NPR-C signaling, unfortunately it is presently not commercially available. Described is a detailed protocol for its synthesis that does not require specialized apparatus and builds upon a prior patent from Veale and colleagues. Key steps include a base-mediated lactam formation and a solid-supported peptide synthetic sequence. An X-ray crystal structure of a key lactam intermediate was obtained to confirm the structure and relative …

Understanding The Oxidative Chemistry Of Particulate Methane Monooxygenase Models., Thomas Jones

Research Horizons Day Posters

No abstract provided.

Synthesis Of Novel Thiazole And Pyrazole Derivatives As Antimicrobial And Anticancer Agents, Rawan Saleh Alnufaie

Student Theses and Dissertations

This thesis contains three chapters. In Chapters One and Two, we report the synthesis of new pyrazole derivatives by using naphthalene-derived and coumarin-derived aldehydes. We have synthesized 61 different pyrazole derivatives in good yield. In the third chapter, a new methodology to synthesize thiazole derivatives is reported. In this methodology, the reaction was performed without column purification and work-up. Readily available starting materials were used with mild reaction conditions. Acetic acid was used as a solvent in this reaction to synthesize 34 new compounds. All these compounds were characterized by using NMR spectroscopy and mass spectrometry. These compounds were tested …

Synthesis Of A Protected 2-Aminocyclobutanone As A Modular Transition State Synthon For Medicinal Chemistry, Thahani S. Habeeb Mohammad, Cory T. Reidl, Matthias Zeller, Daniel P. Becker Ph.D.

Chemistry: Faculty Publications and Other Works

The hydrochloride salt of ɑ-aminocyclobutanone protected as its dimethyl acetal 2,2-dimethoxycyclobutan-1-aminium chloride (3) has been prepared as a modular synthon for convenient access to cyclobutanone-containing lead inhibitors of hydrolase enzymes including serine proteases and metalloproteases. Protected ɑ-aminocyclobutanone 3 was converted to representative amide and sulfonamide-functionalized 2-aminocyclobutanone derivatives. Reaction of the amino acetal 3 with phenyl isothiocyanate afforded the bicyclic urea 1-hydroxyl-2,4-diazabicyclo[3.2.0]heptane-3-thione (9) as confirmed by a single crystal X-ray structure.

Regenerative Electroless Etching (U.S. Patent), Kurt W. Kolasinski, Jarno Salonen, Ermei Makila

Chemistry Faculty Publications

A regenerative electroless etching process produces nanostructured semiconductors in which an oxidant (Ox 1 ) is used as a catalytic agent to facilitate reaction between a semiconductor and a second oxidant (Ox2) that would be unreactive (or slowly reactive compared to Ox 1 ) in the primary reaction. Ox2 is used to regenerate Ox1 , which can initiate etching by injecting holes into the semiconductor valence band. The extent of reaction is controlled by the amount of Ox2 added; the reaction rate, by the injection rate of Ox2 . This general strategy is demonstrated specifically to produce highly luminescent nanocrystalline …

Comparative Analysis Of The Human Serine Hydrolase Ovca2 To The Model Serine Hydrolase Homolog Fsh1 From S. Cerevisiae, Jessica S. Bun, Michael D. Slack, Daniel E. Schemenauer, R. Jeremy Johnson

Scholarship and Professional Work - LAS

Over 100 metabolic serine hydrolases are present in humans with confirmed functions in metabolism, immune response, and neurotransmission. Among potentially clinically relevant but uncharacterized human serine hydrolases is OVCA2, a serine hydrolase that has been linked with a variety of cancer-related processes. Herein, we developed a heterologous expression system for OVCA2 and determined the comprehensive substrate specificity of OVCA2 against two ester substrate libraries. Based on this analysis, OVCA2 was confirmed as a serine hydrolase with a strong preference for long-chain alkyl ester substrates (>10-carbons) and high selectivity against a variety of short, branched, and substituted esters. Substitutional analysis …

Fiber-Optic Micro-Probes For Measuring Acidity Level, Temperature, And Antigens, Yinfa Ma, Honglan Shi, Qingbo Yang, Hai Xiao

Chemistry Faculty Research & Creative Works

A pH micro-probe, a temperature micro-probe, and an immuno-based micro-probe each include a shaft for transmuting an input light signal and a tip for inserting into a cell or other substance for measuring pH, temperature, and/or antigens. The pH micro-probe and the temperature micro-probe each include a luminescent material positioned on the tip of the micro-probe. The light signal excites the luminescent material so that the luminescent material emits a luminescent light signal. The luminescent light signal has a property value dependent on the pH or temperature being measured and reflects back through the shaft for being measured by a …

Methanethiol, Dimethyl Sulfide And Acetone Over Biologically Productive Waters In The Southwest Pacific Ocean, Sarah J. Lawson, Cliff S. Law, Mike J. Harvey, Thomas G. Bell, Carolyn F. Walker, Warren J. De Bruyn, Eric S. Saltzman

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Atmospheric methanethiol (MeSH_a), dimethyl sulfide (DMS_a) and acetone (acetone_a) were measured over biologically productive frontal waters in the remote southwest Pacific Ocean in summertime 2012 during the Surface Ocean Aerosol Production (SOAP) voyage. MeSH_a mixing ratios varied from below the detection limit (< 10 ppt) up to 65 ppt and were 3 %–36 % of parallel DMS_a mixing ratios. MeSH_a and DMS_a were correlated over the voyage (R²=0.3, slope = 0.07) with a stronger correlation over a coccolithophore-dominated phytoplankton bloom (R²=0.5, slope 0.13). The diurnal cycle for MeSH_a shows similar behaviour to DMS_a with mixing ratios …

Semester-Long Course-Based Research Project In Second-Semester Organic Chemistry: Synthesizing Potential Lead Compounds For The Treatment Of A Neglected Tropical Disease, Kerry L. Barnett, Kevin M. Shea, Catherine Mcgeough, Kristine Trotta, Steven A. Williams, Minh Ly, Kathryn Aloisio

Chemistry: Faculty Publications

A semester-long research project for second-semester organic chemistry lab sections was developed. Student projects were based on preliminary data from faculty research that suggested the natural product neurolenin B to be a treatment for lymphatic filariasis. Students isolated neurolenins from the Central American plant Neurolaena lobata and proposed syntheses of previously unknown analogues using reactions learned in first- and second-semester organic chemistry. Using literature-based procedures, students ran reactions on neurolenins and analyzed their results by TLC and NMR spectroscopy. The semester culminated with a public poster session and final report using the Organic Letters template. Students in a total of …

Ambient Air Quality In The Kathmandu Valley, Nepal, During The Pre-Monsoon: Concentrations And Sources Of Particulate Matter And Trace Gases, Md Robiul Islam, Thilina Jayarathne, Isobel J. Simpson, Benjamin Werden, John Maben, Ashley Gilbert, Puppala S. Praveen, Sagar Adhikari, Arnico K. Panday, Maheswar Rupakheti, Donald R. Blake, Robert J. Yokelson, Peter F. Decarlo, William C. Keene, Elizabeth A. Stone

Chemistry and Biochemistry Faculty Publications

The Kathmandu Valley in Nepal is a bowl-shaped urban basin that experiences severe air pollution that poses health risks to its 3.5 million inhabitants. As part of the Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE), ambient air quality in the Kathmandu Valley was investigated from 11 to 24 April 2015, during the premonsoon season. Ambient concentrations of fine and coarse particulate matter (PM2:5 and PM10, respectively), online PM1, inorganic trace gases (NH3, HNO3, SO2, and HCl), and carbon-containing gases (CO2, CO, CH4, and 93 nonmethane volatile organic compounds; NMVOCs) were quantified at a semi-urban location near the center of …

Restructuring A General College Chemistry Sequence Using The Acs Anchoring Concepts Content Map, Scott A. Reid

Chemistry Faculty Research and Publications

Many STEM (science, technology, engineering, and mathematics) disciplines require a two-semester sequence of introductory college chemistry, which are thus critical gateway courses to a variety of majors. Recognizing the benefit to educators of a structure of content learning across the chemistry curriculum, in 2012, the American Chemical Society (ACS) developed the Anchoring Concepts Content Map, or ACCM. The development and subsequent revision of the general chemistry ACCM inspired the restructuring of our first-year chemistry sequence. Thus our CHEM 1001 and 1002 courses, taught in an atoms-first framework, were reorganized into a set of nine modules, each intentionally linked to one …

Tuning Internal Strain In Metal–Organic Frameworks Via Vapor Phase Infiltration For Co2 Reduction, Fan Yang, Wenhui Hu, Chongqing Yang, Margaret Patrick, Andrew L. Cooksy, Jian Zhang, Jeffery A. Aguiar, Chengcheng Fang, Yinghua Zhou, Ying Shirley Meng, Jier Huang, Jing Gu

Chemistry Faculty Research and Publications

A gas-phase approach to form Zn coordination sites on metal–organic frameworks (MOFs) by vapor-phase infiltration (VPI) was developed. Compared to Zn sites synthesized by the solution-phase method, VPI samples revealed approximately 2.8 % internal strain. Faradaic efficiency towards conversion of CO₂ to CO was enhanced by up to a factor of four, and the initial potential was positively shifted by 200–300 mV. Using element-specific X-ray absorption spectroscopy, the local coordination environment of the Zn center was determined to have square-pyramidal geometry with four Zn−N bonds in the equatorial plane and one Zn-OH₂ bond in the axial plane. The …

Characterization Of Dimerization Domains On The Mannose-6-Phosphate/Insulin-Like Growth Factor 2 Receptor, Tyler Degener

UNO Student Research and Creative Activity Fair

The mannose-6-phosphate/insulin-like growth factor 2 (M6P/IGF2) receptor is a transmembrane protein with the ability to sequester growth factors from the extracellular matrix. This behavior links the receptor to tumor suppression. On a structural level, the extracellular portion of the protein is segmented into 15 homologous repeats, which can be divided further into 5 triplet domains, labelled 1-3, 4-6, 7-9, 10-12, and 13-15. Each triplet receptor displays its own unique ligand binding affinity, including the ability to form dimers with triplets on a second M6P/IGF2 receptor. In fact, previous studies indicate that this protein functions optimally when dimerized. Thus, the purpose …

Design, Construction, And Characterization Of A Low-Cost Spectrometer With Interchangeable Parts, Jack Godek

UNO Student Research and Creative Activity Fair

A low-cost spectrometer was designed for the purpose of teaching spectroscopy. The spectrometer can be built by the student and contains interchangeable pieces such as slit width, grating, and lenses. This will allow the student to understand how changing these variables effects resolution. The spectrometer was constructed from PVC pipe, a plastic electrical box, and a USB webcam. The actual resolution of the spectrometer is close to the theoretical value, depending on which lens and grating is used. In addition, an extra piece can be added that allows absorption spectra to be collected. Having the student piece together the spectrometer …

Optoelectronic Properties Of Carbon-Bound Boron Difluoride Hydrazone Dimers, Daniela Cappello, Ryan R. Maar, Viktor N. Staroverov, Joe Gilroy

Chemistry Publications

The creation of dimeric boron difluoride complexes of chelating N-donor ligands is a proven strategy for the enhancement of the optoelectronic properties of fluorescent dyes. We report dimers based on the boron difluoride hydrazone (BODIHY) framework, which offer unique and sometimes unexpected substituent-dependent absorption, emission, and electrochemical properties. BODIHY dimers have low-energy absorption bands (l_max = 421 to 479 nm, e = 17,200 to 39,900 M⁻¹ cm⁻¹) that are red-shifted relative to monomeric analogues. THF solutions of these dimers exhibit aggregation-induced emission upon addition of water, with emission enhancement factors ranging from 5 to 18. …

Interactions Between The Azoarcus Ribozyme And Manganese (Ii) Divalent Cations, Joshua Martwick

University Honors Theses

The RNA world hypothesis suggests that RNA systems were the first form of life on the planet, beginning to appear approximately 4 billion years ago. Group I introns are self-splicing RNA elements in extant organisms and use Mg²⁺ as the principle divalent cation to promote catalysis. The group I intron ribozyme from Azoarcus is frequently used in origin of life studies, partially due to its autocatalytic abilities - the Azoarcus ribozyme is able to be broken into fragments and reassemble itself into its fully functional ribozyme. Previous work identified metal binding sites on the Azoarcus ribozyme which use both …

A Neuro-Ontology For The Neurological Examination, Daniel B. Hier, Steven U. Brint

Chemistry Faculty Research & Creative Works

Background: The Use of Clinical Data in Electronic Health Records for Machine-Learning or Data Analytics Depends on the Conversion of Free Text into Machine-Readable Codes. We Have Examined the Feasibility of Capturing the Neurological Examination as Machine-Readable Codes based on UMLS Metathesaurus Concepts. Methods: We Created a Target Ontology for Capturing the Neurological Examination using 1100 Concepts from the UMLS Metathesaurus. We Created a Dataset of 2386 Test-Phrases based on 419 Published Neurological Cases. We Then Mapped the Test-Phrases to the Target Ontology. Results: We Were Able to Map All of the 2386 Test-Phrases to 601 Unique UMLS Concepts. a …

Assessing The Ecological Risk Of Heavy Metal Sediment Contamination From Port Everglades Florida, Dimitri G. Giarikos, Laura White, Amy C. Hirons

SECLER Data

Port sediments are often contaminated with metals and organic compounds from anthropogenic sources. Port dredging can remobilize contaminated sediments, resulting in harmful impacts to the benthic community. Twelve sediment cores were collected from four Port Everglades, Florida sites and a control site; surface sediment was collected at two nearby coral reef sites. Sediment cores, sampled every 5 cm, were quantified for 14 heavy metals using induced coupled plasma mass spectrometry (ICPMS). Geo-accumulation index shows moderate-to-strong contamination of As and Mo in port sediments, and potential ecological risk indicates moderate-to-significantly high overall metal contamination. Arsenic port sediment concentrations exceed threshold effect …

Long-Term Variations (2001-2016) Of Satellite-Based Pm2.5 Concentrations And Its Determinants In Xinjiang, Northwest Of China, Wei Wang, Alim Samat, Jilili Abuduwaili

Karakalpak Scientific Journal

Based on the long-term series of satellite-retrieved PM2.5 concentrations, this study explored the spatiotemporal variation and aggregation characteristics of PM2.5 concentrations in Xinjiang from 2001 to 2016 by using standard deviational ellipse analysis and spatial autocorrelation statistics method. The result showed that the annual average PM2.5 concentrations was high in the north slope of Tianshan mountain and the western Tarim desert where High-High clusters mainly distribute. Furthermore, PM2.5 concentrations in the north slope of Tianshan mountain increased significantly from 2001 to 2016. Based on the result of GeoDetector model, population density was the most dominant factor of PM2.5 concentrations (q=0.55). …

Influence Of The Glycirrizin Acid Complex On Fungal Diseases Of Winter Wheat, U. Shapulatov, M. K. Allaniyazova, S. Kh. Khozhiboboeva, Kh. Kh. Kushiev

Karakalpak Scientific Journal

This work presents the results of studies of the effect of glycyrrhizic acid complexes on phytoptogens and the growth and development of wheat. The study of the action of growth regulators in the field often leads to mixed results that GA: TA GA-Cu, GA-Zn, GA: YES, GA: BT significantly reduces the charge level of wheat with parasitic diseases. However, the positive effect of the studied drugs is limited by fungistatic activity. The exceptionally positive role of glycyrrhizic acid complexes indicates the need for a wide study of silicon fertilizers and their introduction into the production of grain crops. The ambiguity …

Development Of Hplc Separation Method Of Ginsenosides On A Polyvinyl Alcohol-Bonded Stationary Phase, A. B. Soliev, A. T. Adylova, I. Yu. Abdurakhmonov, G. N. Artikova

Karakalpak Scientific Journal

A simple high performance liquid chromatographic assay for the simultaneous quantitative analysis of seven ginsenosides, Rb1, Rb2, Rc, Rd, Re, Rf and Rg1 in commercial ginseng products is described. Chromatographic separation of the analytes was achieved in less than 20 min using a polyvinyl alcohol-bonded column with UV detection at 203 nm. Optimization of chromatographic conditions was determined by a three-factor central composite design, the variables being the percentage of acetonitrile in the mobile phase, column temperature and flow rate. A full quadratic model was found to be adequate in describing the separation of ginsenosides on the polyvinyl alcohol-bonded stationary …

Optimization Of A Digital Ion Trap To Perform Isotope Ratio Analysis Of Xenon For Planetary Studies, Timothy Vazquez

USF Tampa Graduate Theses and Dissertations

Ion trap mass spectrometers present a powerful analytical tool which not only enables mass spectrometric determination of analyte species but also has the added feature of being able to act as an ion storage device. As a mass spectrometer, ion traps can achieve a reasonable mass range with flexible mass resolution while boasting a considerably smaller footprint when compared to conventional time-of-flight or magnetic sector instruments. Due to their smaller geometries, high-pressure tolerance, and ability to perform tandem mass spectrometry, ion trap mass spectrometers are ideal candidates for portable applications such as deployment to another planetary body. While ideal candidates …

Crystal Structure Of Pantoprazole Sodium Sesquihydrate Form I, C16h14f2n3o4sna(H2o)1.5, Diana Gonzalez '20, Joseph T. Golab, James A. Kaduk, Amy M. Gindhart, Thomas N. Blanton

Student Publications & Research

No abstract provided.

Powder X-Ray Diffraction Of Fluorometholone, C22h29fo4, Diana Gonzalez '20, Joseph T. Golab, James A. Kaduk, Amy M. Gindhart, Thomas N. Blanton

Student Publications & Research

No abstract provided.

Powder X-Ray Diffraction Of Flucytosine, C4h4fn3o, Nilan V. Patel, Joseph T. Golab, James A. Kaduk, Amy M. Gindhart, Thomas N. Blanton

Student Publications & Research

No abstract provided.