Other Chemistry Commons^™

Modification Of Chm20 Lab: Synthesis Of Aspirin, Nicole Diaz, Amy Musselman Prof.

KU Inspires! Undergraduate Research Day

No abstract provided.

Mechanistic Study Of Cooperative Ligand-Centered Reactivity In Triaminoborane-Bridged Diphosphine Complexes, Clara Kirkvold

Honors Thesis

Reactive ligand platforms containing trisubstituted boranes have been effective in promoting new types of small molecule reactivity and catalysis with transition metals. Our project is aimed at developing triaminoborane-bridged diphosphines that participate in cooperative ligand-centered reactivity while bound to transitions metals. Here we present a density functional theory (DFT) mechanistic study on a series of ligand centered reactions at a boron center on a metal complex, ^PhTBDPhosMCl₂ (M = Ni or Pd and TBDPhos = 1,8,10,9-triazaboradecalin). Our work focuses specifically on the nickel complexes. ^PhTBDPhosNiCl₂ can react with several molecules to produce trans H-X addition ...

Isolation, Identification, And Investigation Of A Novel Bioactive Furanocoumarin From Leaves Of Amyris Elemifera, Amy K. Bracken

Honors Theses

Plants produce biologically active compounds that humans have utilized for many agricultural applications. Amyris elemifera was investigated due to the known bioactivity of its family, Rutaceae, and its use in medicines in tribes of the Bahamas. Biotage® and TLC guided fractionation of the EtOAc, hexane, and MeOH extracts of the leaves of Amyris elemifera yielded bioactive compounds. Most significantly, a novel furanocoumarin, 8-(3-methylbut-2-enyloxy)-marmesin acetate (1), and its analog 8-(3-methylbut-2-enyloxy)-marmesin (2), were isolated. The structures were identified via NMR and X-ray crystallography techniques; the X-ray crystal structure for 1 was reported for the first time, and the ...

Effect Of Charged Lipids On The Ionization Behavior Of Glutamic Acid Containing Transmembrane Helices, Brooke Nunn

Chemistry & Biochemistry Undergraduate Honors Theses

Transmembrane proteins make up critical components of living cells. Protein function can be greatly impacted by the charged state of its respective components, the side chains of amino acid residues. Thus far, in the lipid membrane, little is known about the properties of residues such as glutamic acid. To explore these properties, I have included glutamic acid in a suitable model peptide-lipid system for fundamental biophysical experiments. Within the system, I have placed a glutamic acid residue instead of leucine in the L14 position of the helical hydrophobic peptide GWALP23 (acetyl-GGALWLALALALAL¹⁴ALALWLAGA-amide). Substitutions of glutamine and aspartic acid serve ...

Resolution Of Portable Raman Spectrometers And Its Effect On The Analysis Of Biological Specimens, Jalissa Thomas

Chemistry

Body fluid traces are a common and a major form of evidence that can be found at a crime scene, as it is a good source of DNA. As such, it is vital that body fluid evidence is properly detected and identified. Issues with the current methods of identifying body fluids and the large backlog of evidence in most forensic labs call for more accurate on-scene (in situ) body fluid identification. Past research has demonstrated that Raman spectroscopy is an advantageous tool for accurately and quickly identifying body fluids, namely in the laboratory. Portable Raman instruments have been created to ...

Determination Of Thermodynamic Properties Of Non-Protein Amino Acids And Characterization Of Multimers Of Carbamazepine, Gwendylan Turner

Undergraduate Honors Theses

This study has two seemingly unrelated parts that come together remarkably in displaying the comprehensive interplay between chemical structure and properties as well as the variety of analytical applications of mass spectrometry.

The first part of this study describes the determination of thermodynamic properties of several non-protein amino acids using the extended kinetic method. This is a continuation of work started in the Poutsma lab in Spring of 2017. The non-protein amino acids (NPA) studied here hold notable relevance in their unique ability to be mis-incorporated into peptide chains, as shown by the Hartman group at Virginia Commonwealth University.^{[1 ...}

295— Biomimicry: Investigating The Active Site Model Of Lactate Racemase, Stephanie Podguski, Maisy Ross

GREAT Day

Because of humans’ heavy impact on nature with industrialization and resource extraction, biomimetics, also known as biomimicry, is a study that has emerged. Biomimetics utilizes observations from nature to comprehend the principles of underlying mechanisms and apply concepts that may benefit science, medicine, engineering and the like. An area of biochemistry we are applying this to is the lactate racemase enzyme.This metalloenzyme is found in many prokaryotic organisms and catalyzes the interconversion between the two optical isomers of lactic acid. The structure of this enzyme consists of a square-planar nickel (II) ion coordinated by a histidine residue and a ...

Quantum Chemical Lipophilicities Of Antimalarial Drugs In Relation To Terminal Half-Life, Joseph D. Alia, Sheila Karl, Tyler D. Kelly

Chemistry Publications

According to the WHO, artemisinin-based combination therapies (ACTs) have been integral to the recent reduction in deaths due to Plasmodium falciparum malaria. ACT-resistant strains are an emerging problem and have evolved altered developmental stages, reducing exposure of the most susceptible stages to artemisinin drugs in popular ACTs. Lipophilicity, log K_ow, is a guide in understanding and predicting pharmacokinetic properties such as terminal half-life which alters drug exposure. Consistent log K_ow values are not necessarily available for artemisinin derivatives designed to extend terminal half-life, increase bioavailability, and reduce neurotoxicity. For other drugs used in ACTs, an assortment of experimental ...

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

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 ...

The Use Of A Modified Hess’ Cognitive Rigor Matrix To Assess Students’ Depth Of Knowledge In Key Concepts Of Gas Stoichiometry And Chemical Equilibrium, Maria Greene

All Dissertations, Theses, and Capstone Projects

The research presented as part of this dissertation is a combination of two separate studies conducted to assess and evaluate undergraduate general chemistry students’ understanding and depth of knowledge (DOK) of concepts in gas stoichiometry and chemical equilibrium. The two separate studies were conducted using a modified Hess Cognitive Rigor Matrix (CRM) to analyze students’ responses to multiple-choice questions (MCQ) and their written rationales to their answer choices. The Hess Cognitive Rigor Matrix, which is an incorporation and coordination of both Bloom’s and Webb’s DOK taxonomies, allowed the facilitation of the opportunity to code students’ written responses across ...

Resolving The Puzzle Of Single-Atom Silver Dispersion On Nanosized Γ-Al2o3 Surface For High Catalytic Performance, Fei Wang, Jinzhu Ma, Shaohui Xin, Qiang Wang, Jun Xu, Changbin Zhang, Hong He, Xiao Cheng Zeng

Faculty Publications -- Chemistry Department

Ag/γ-Al2O3 is widely used for catalyzing various reactions, and its performance depends on the valence state, morphology and dispersion of Ag species. However, detailed anchoring mechanism of Ag species on γ-Al2O3 remains largely unknown. Herein, we reveal that the terminal hydroxyls on γ-Al2O3 are responsible for anchoring Ag species. The abundant terminal hydroxyls existed on nanosized γ-Al2O3 can lead to single-atom silver dispersion, thereby resulting in markedly enhanced performance than the Ag cluster on microsized γ-Al2O3. Density-functional-theory calculations confirm that Ag atom is mainly anchored by the terminal hydroxyls on (100) surface, forming a staple-like local structure with each ...

Determination Of The Free Energies Of Mixing Of Organic Solutions Through A Combined Molecular Dynamics And Bayesian Statistics Approach, Shi Li, Balaji Sesha Sarath Pokuri, Sean Ryno, Asare Nkansah, Camron De’Vine, Baskar Ganapathysubramanian, Chad Risko

Mechanical Engineering Publications

As new generations of thin-film semiconductors are moving towards solution-based processing, the development of printing formulations will require information pertaining to the free energies of mixing of complex mixtures. From the standpoint of in silico materials design, this move necessitates the development of methods that can accurately and quickly evaluate these formulations in order to maximize processing speed and reproducibility. Here, we make use of molecular dynamics (MD) simulations in combination with the two-phase thermodynamic (2PT) model to explore the free energy of mixing surfaces for a series of halogenated solvents and high boiling point solvent additives used in the ...

Carbon Oxidation State In Microbial Polar Lipids Suggests Adaptation To Hot Spring Temperature And Redox Gradients, Grayson M. Boyer, Florence Schubotz, Roger E. Summons, Jade Woods, Everett L. Shock

Faculty Publications -- Chemistry Department

The influence of oxidation-reduction (redox) potential on the expression of biomolecules is a topic of ongoing exploration in geobiology. In this study, we investigate the novel possibility that structures and compositions of lipids produced by microbial communities are sensitive to environmental redox conditions. We extracted lipids from microbial biomass collected along the thermal and redox gradients of four alkaline hot springs in Yellowstone National Park (YNP) and investigated patterns in the average oxidation state of carbon (Z_C), a metric calculated from the chemical formulae of lipid structures. Carbon in intact polar lipids (IPLs) and their alkyl chains becomes more ...

Surface Modification Of Silicon Nanowire Based Field Effect Transistors With Stimuli Responsive Polymer Brushes For Biosensing Applications, Stephanie Klinghammer, Sebastian Rauch, Sebastian Pregl, Petra Uhlmann, Larysa Baraban, Gianaurelio Cuniberti

Faculty Publications -- Chemistry Department

We demonstrate the functionalization of silicon nanowire based field effect transistors (SiNW FETs) FETs with stimuli-responsive polymer brushes of poly(N-isopropylacrylamide) (PNIPAAM) and poly(acrylic acid) (PAA). Surface functionalization was confirmed by atomic force microscopy, contact angle measurements, and verified electrically using a silicon nanowire based field effect transistor sensor device. For thermo-responsive PNIPAAM, the physicochemical properties (i.e., a reversible phase transition, wettability) were induced by crossing the lower critical solution temperature (LCST) of about 32 ◦C. Taking advantage of this property, osteosarcomic SaoS-2 cells were cultured on PNIPAAM-modified sensors at temperatures above the LCST, and completely detached by ...

Synthesis Of Unsymmetrical Bidentate Ligands From Secondary Phosphine Oxides, Malachy J. Brink, Ryan Anderson

Student Research, Papers, and Creative Works

Stereochemistry is a key component in the field of asymmetric catalysis. The properties of a molecule can be drastically changed with the change of one stereocenter. Typically, chirality is imparted to a metal by the ligand. "Chiral-at-metal" compounds are unique because the metal complex is chiral, but the ligands are not. Phosphine ligands are notoriously difficult to work with (pyrophoric, toxic, prone to oxidation). The goal of this research was to prepare unsymmetrical bidentate ligands using secondary phosphine oxides, which are air-stable and easy to handle on the benchtop.

The Role Of Influenza Infection On Cell Metabolism, Megha Mokkapati

Williams Honors College, Honors Research Projects

In this particular study global metabolomics LCMS data was analyzed to determine the effect of influenza infection on host metabolic processes. Specifically, wild-type male and female mouse lung samples from mice infected with PR8 (H1N1) or both PR8 and a reinfection of X31 (H3N2) were analyzed. The LC/MS(liquid chromatography-mass spectrometry) based global metabolomics will be performed on the samples using hydrophilic interaction liquid chromatography to separate polar analytes from the tissues (Dettmer, Aronov, 2007). Metabolites impacted by influenza infection in all samples will be analyzed to compare male and female mice, as well as differences between PR8 infection ...

A Comparative Study Of Drug Affinities Determined By Thermofluor And Kinetic Analysis, Oruba Shatnawi

Theses, Dissertations and Culminating Projects

Determining the binding affinity and potency in vitro is one of the significant steps that can give a clue for a new candidate drug during the drug discovery process. Thermofluor is a method used in measuring binding affinity (Kd) of protein-ligands interaction through determining the change in thermal denaturation temperature of protein using real time PCR (RT-PCR). Kinetic analysis assay is used to screen a library of compounds to calculate their potencies (IC50) and inhibition constants (Ki) and it can be performed by spectrophotometer technique. In this study, we used bovine carbonic anhydrase II (BCA II) enzyme, and four of ...

A Theoretical Study An Influence Of Oxygen Group Elements To Rotational Barrier Of 2-(2'-Pyridyl)-1,3,4-Oxa(Thia, Selena And Tellura) Diazoles, Alisher Eshimbetov, Khamza Toshov, Inderpreet Kaur, Alisher Khaitboev

Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences

Surveying of the references shows that selenium and tellurium containing compounds will be one of the most promising heterocycles in the future. Therefore, the influence of oxygen group elements -- O, S, Se and Te to rotational barrier heights of 2-(2'-pyridyl)-1,3,4-oxa (thia, selena and tellura) diazoles were investigated by DFT/def2-TZVP method and also by DFT/6-311G(d) method only for O, S and Se series. And also, their thermodynamic parameters (ΔH,ΔG) were calculated in gas phase. Furthermore, some model compounds with conjugated C=C-C=C, N=C-C=C and N=C-C=N fragments with ...

“Treat Me Covalently” – New Tools To Improve Covalent Drug Design For Advancement Of Cancer Treatments, Yuliya Mazo

Student Theses

The goal of this project was to investigate the complex mechanism of covalent bonding among different molecules and their targets in a modeling software ICM-Pro. Specifically, it included the identification of fundamental aspects of a covalent bonding mechanism of the Michael addition reaction. Michael addition reaction of electrophilic α, β-unsaturated carbonyl compounds with a nucleophilic cysteine residue in thymidylate synthase, papain, and EGFR tyrosine kinase were examined. Thymidylate synthase and EGFR were chosen because they are important targets in the treatment of various types of cancer. In order to find the most optimal parameters, identification and assessment of the effect ...

Evaluation Of Tumor Necrosis Factor Alpha In Sleep-Deprived Menopausal- Induced Rats And The Impact On Bone Health, Nicole Ellsworth, Dwight Curry Iii, Cj Deleon, Frank Frisch

Student Scholar Symposium Abstracts and Posters

Post-menopausal osteoporosis as a consequence of estrogen depletion is a growing concern for women in the United States. As more women take on executive positions and experience sleep deprivation, there is the potential for up regulation of pro-inflammatory cytokines, such as tumor necrosis factor alpha. It follows that the homeostatic imbalance of osteoclastic and osteoblastic activity leads to a greater risk of disease. Bisphosphonates generally, and Zolendronate specifically works by decreasing the number of osteoclasts. This current study investigated the impact of Zolendronate on the concentrations of tumor necrosis factor alpha-type (TNFɑ) in 32 ovariectomized Wistar rats. Throughout a five ...