Physical Sciences and Mathematics Commons^™

Separating The R Vs. S Enantiomers Of A Quinoline Aimed At Inhibiting The Allosteric Binding Pocket Of Hiv-1 Integrase, Madison Canfield

Honors Theses

HIV-1 is a retroviral disease that infects CD4+ T cells in the body. Once inside the body, HIV-1 uses human cell machinery to replicate and reproduce using several enzymes to reverse transcribe viral RNA to DNA and integrate the viral DNA into the human genome to reproduce. Several drugs, such as NRTIs, INSTIs, NNRTIs, and PIs, have been created to inhibit specific parts of the viral life cycle and are used in combination to fight HIV-1. However, these medications face challenges of viral mutation and resistance, which increases the importance of creating more potent and effective drugs. Recently, a new …

Separating The R Vs. S Enantiomers Of A Quinoline Aimed At Inhibiting The Allosteric Binding Pocket Of Hiv-1 Integrase, Madison Canfield

Honors Theses

HIV-1 is a retroviral disease that infects CD4+ T cells in the body. Once inside the body, HIV-1 uses human cell machinery to replicate and reproduce using several enzymes to reverse transcribe viral RNA to DNA and integrate the viral DNA into the human genome to reproduce. Several drugs, such as NRTIs, INSTIs, NNRTIs, and PIs, have been created to inhibit specific parts of the viral life cycle and are used in combination to fight HIV-1. However, these medications face challenges of viral mutation and resistance, which increases the importance of creating more potent and effective drugs. Recently, a new …

Modeling Surface Structures For The Capture Of Carbon Dioxide, Paige Freyre

Honors Theses

Our research utilized a modified graphene surface model to simulate capture of carbon dioxide and nitrogen gas based on van der Waals forces and hydrogen bonding. We completed an extensive review of the literature for model and experimental surfaces used to trap carbon dioxide and nitrogen gas into structures and pores with varying functional groups, pore sizes, and pore structures. We replicated the design of selected published models and compared their and our calculated binding energies. We used Scigress (Fujitsu) software with the Molecular Mechanics MM3 parameter set to perform calculations to analyze a proposed graphene surface pore lined with …

Synthetic Investigations In Chemical Probe Development Part 1: Design And Synthesis Of Novel Triton X-405 Adenosine Conjugates; Part 2: Synthesis Of 2,8-Dihydroxychrysene, Rachel Irene Hammond

Honors Theses

Although not drugs themselves, chemical probes are a necessary tool in biomedical research for the interrogation of biological systems. In the present synthetic investigation, two chemical probes were developed – a Triton X-405 adenosine conjugate (TX-405A) and 2,8-dihydroxychrysene. The designed TX-405A conjugate was generated in four steps through tosylation and amination of TX-405 such that EDC-coupling of TX-amine with 2’,3’-Isopropylidene adenosine-5’-carboxylic acid afforded TX-405A following acetonide deprotection. The development of TX-405A represents the first report of the synthesis and utilization of a detergent-linked dosimeter. The synthesis of 2,8-dihydroxychrysene provided an in-depth exploration on the unique reactivity of chrysene. The desired …

Synthesis And Study Of Unsymmetrical Bidentate Bis(Phosphino)Pyrrole Ligands And Their Transition Metal Complexes, Julia F. Vidlak

Honors Theses

Our laboratory has reported the synthesis and characterization of a broad library of unsymmetrical bidentate bis(phosphino)pyrrole (BPP) ancillary ligands for use in nickel-catalyzed cross-coupling reactions. The electronic and steric properties of nickel complexes bearing these ligands are examined, and our data support the hypothesis that these ligands produce nickel complexes with electron-deficient metal centers. The syntheses of (BPP)Ni(o-tolyl)Cl precatalysts for utilization in nickel-catalyzed Buchwald-Hartwig Amination are described, and preliminary reactivity studies reveal that (BPP)Ni(o-tolyl)Cl precatalysts are effective in promoting C–N cross-coupling reactions. Finally, we report steric measurements and electronic properties obtained from computed (BPP)NiCl2 and (BPP)Ni(CO)2 complexes, respectively. Additional reactivity …

Fast Photochemical Oxidation And Footprinting Of Proteins Via Trifluoromethyl Radical Chemistry, Elaine Morrow

Honors Theses

Fast photochemical oxidation of proteins (FPOP) is a useful tool in proteomics because of the ability for modifications to occur on the scale of microseconds which reduces the modifications to tertiary and quaternary structure allowing for more accurate labeling of the protein. Labels for FPOP are generated from various radicals in our experiments which include hydroxyl radicals and trifluoromethyl radicals. Hydroxyl radicals are easily generated by using an excimer laser (KrF laser, 248 nm) or a UV flash lamp (as a part of the Fox™ System) by the photolysis of hydrogen peroxide. Trifluoromethyl radicals, however, need hydroxyl radicals to be …

Investigation Of N-Sulfonyliminium Ion Triggered Cyclizations For The Synthesis Of Piperidine Scaffolds, Kaitlyn Birkhoff

Honors Theses

In consideration of the on-going global pandemic, immediate access to Food and Drug Administration approved pharmaceutical medications and vaccines is a matter of utmost priority to our national healthcare system. One significant modality in managed care is the dispensation of prescription drugs for the prevention or treatment of illnesses and diseases. According to the Centers for Disease Control and Prevention, physicians order and provide over 2.9 billion prescriptions each year with analgesics, antihyperlipidemics, and dermatological agents being the most prescribed therapeutic classes. Within those classes exists a disparate variety of chemical structures that must be prepared on a metric ton …

Techniques For The Enantioselective Asymmetric Synthesis Of Benzyl Substituted Malonic Acid Esters, Madison Hansen

Honors Theses

A popular method for the enantioselective synthesis of substituted malonic half esters is hydrolysis via Pig Liver Esterase (PLE), however some substrates produce low enantiomeric excess, namely benzyl-substituted malonic esters. Presented here are alternative methods explored for this synthesis, the first being phase-transfer catalyzed hydrolysis via N-benzyl quaternary ammonium salts derived from cinchona alkaloids. The second method utilized chiral auxiliary directed benzylation with auxiliaries including menthol and oxazolidinones. Though unsuccessful, this research provided valuable groundwork in the investigation for the enantioselective asymmetric synthesis of benzyl-substituted malonic acid esters.

Keywords: Pig Liver Esterase, Enantioselectivity, Phase-Transfer Catalysis, Cinchona Alkaloids, Quaternary Ammonium …

One-Pot Synthesis Of Disubstituted Primary Amines From Nitriles Via Grignard Addition And Metal-Alcohol Reduction, Joshua Peltan

Honors Theses

The process of developing a working base case procedure for a novel one-pot-two-step synthesis of primary amines from Grignard reagents, nitriles, sodium metal or alkali metal loaded silica gel, and alcohol is described. Initial steps towards applying the process broadly are detailed. The process has the potential to be an affordable, convenient, safer, greener, and more accessible alternative to exiting methods of accomplishing the same transformation. The reaction scheme has been proven to provide yields and purity comparable to existing methods for certain pairs of substrates; however, its utility as a general-purpose method for transforming arbitrary pairs of Grignard reagent …

Applications Of Sodium Azide In The Synthesis Of Tetrazines And Hydrolysis Reactions, My Le

Honors Theses

The inverse electron demand Diels−Alder cycloadditions of heterocyclic azadienes have provided a robust methodology for synthesizing highly substituted and functionalized heterocycles. It is widely used in organic synthesis and the pharmaceutical industry in the divergent construction of screening libraries and bioorthogonal conjugation. Each heterocyclic azadiene was found to possess a unique reactivity toward different classes of dienophiles, display predictable modes of cycloaddition, and exhibit substantial substituent electronic effects impacting their intrinsic reactivity and cycloaddition regioselectivity. Synthesis of 1,2,4,5-tetrazine has been reported in the literature since the late 19th century, showing scientists' tremendous interest in its application.

Herein we attempt to …

Effects Of Halogen Bonding On 13c Nmr Shifts Of Various Tolan Species, Anthony Lybrand

Honors Theses

Halogen bonding is slowly becoming a more and more useful part of the world of chemistry and is beginning to be incorporated into various aspects of the chemical industry. This study’s purpose is to determine whether or not halogen bonding can cause any effect in the 13C NMR shifts. The specific purpose of this study is to determine whether these chemical shifts change when a Lewis Base is added to the dissolved sample. In order to do this, the tolan species (4-iodotolan and 4-chlorotolan) had to be synthesized. Once synthesized, the tolan species were analyzed via NMR. NMR data indicated …

End Group Modification Of Linear Dendritic Block Copolymers (Ldbcs), Chinwe Udemgba

Honors Theses

Linear dendritic block copolymers are amphiphilic molecules that consist of a dendritic hydrophilic portion and a linear hydrophobic portion. Its unique ability to self-assemble into spherical nanoaggregates while having the potential to uptake and transport both hydrophilic and hydrophobic drugs makes these polymers an item of interest in regard to the drug delivery field. The synthesis of polyamidoamine-polylactide linear dendritic block copolymers was designed to address the common issues in drug delivery systems, including problems in permeability, solubility, stability, specificity, and retention. Though this linear dendritic block copolymer has previously been synthesized in our lab with cationic amine surface functionalities, …

Synthesis Of A Dd-Π-Aa Organic Dye For Dye-Sensitized Solar Cells, Hope Lovell

Honors Theses

This project investigates the synthesis of a DD-π-AA (dual donor/dual acceptor) organic dye as a potential sensitizer for dye-sensitized solar cells (DSCs). The design of this dye was based off previous research that found dual donor/dual acceptor dyes exhibited promising results when used in a DSC. The donor groups, acceptor groups, and π-bridge were chosen for their stability, ability to absorb in the near-infrared (NIR) region, and intramolecular charge transfer (ICT) abilities.

While many components of the dye were synthesized, the final stages of the synthetic scheme were not completed due to the loss of time from COVID-19. Had the …

Defying The Darkness: Countering Cancer With Light, Travis Hankins

Honors Theses

Triple-Negative Breast Cancer (TNBC) accounts for upwards of 15% of reported breast cancer cases. This subtype of breast cancer poses a greater threat to those diagnosed as compared to other types of breast cancer due to the lack of treatment options available. Additionally, TNBC grows and spreads faster, tends to be more aggressive, and has a greater chance of recurrence than its counterparts. Altogether, TNBC cases generally have a worse prognosis over other types of breast cancer. Photodynamic therapy (PDT) is currently being researched as a way to treat TNBC. Photodynamic therapy agents are light-activated materials used for localized disease …

Preparation Of Perylene Bisimide Acceptors With Ethylcarboxyl And Pyrenylcyclohexyl Imide Groups, Michael Cashen Stark

Honors Theses

Multiple attempts were made to deprotect TBDMS-protected (tert-butyldimethylsilyl protected) serinol and swallowtailed PBI (Compound 2), synthesized by past researcher Tarrah Frederick, to generate Compound 1. The theoretical Compound 1 product is intended for use in molecular rectification of electricity because the perylene core acts as a good acceptor with high electron affinity, and it does not require an electron donor group. Many rectification molecules are amphiphilic Donor-σ-Acceptor compounds, which allow for electron transfer through localized molecular orbitals when placed between electrodes (Langmuir-Blodgett Method). However, PBIs can transfer electrons from one electrode, through the LUMO of perylene, and to the other …

Indolizine Donor-Based Dyes For Applications In Fluorescence Biological Imaging, William Meador

Honors Theses

NIR emissive fluorophores are intensely researched due to their potential to replace modern imaging procedures. Many molecular strategies have been employed in the literature to optimize fluorophores for deeper NIR absorption and emission, biocompatibility, and higher fluorescence quantum yields. Amongst the fluorophores studied to date, proaromatic indolizine donors are attractive alternatives to traditional alkyl amine and indoline based donors due to their 1) lower energy absorption and emission facilitated by proaromaticity, 2) large Stokes shifts due to increased dihedral angles about the π-system, 3) ease of functionalization and capacity for bioconjugation at the phenyl ring, and 4) potential for further …

Synthesis Of Alkyl Aryl Ethers Using A Halogen Exchange Coupled To An Ullmann Etherification, Antonio Campedelli

Honors Theses

The Ullmann ether synthesis is a reaction that couples aryl halides to aliphatic alcohols. It works best with aryl iodides because the aryl bromides are much less reactive, and aryl chlorides are even more so. A Finkelstein type halogen exchange reaction has been shown to effectively substitute iodide for bromide on aryl bromides with high yields. The goal of this project is to develop a one pot halogen exchange, Ullmann coupling reaction to allow for aryl bromides to be coupled successfully to aliphatic alcohols. This is feasible because the reaction conditions of the two reactions are so similar. Several condition …

Gama-Lactams And The Reformatsky Reaction: New Tricks For Old Chemistry, Dylan Dupont

Honors Theses

DUPONT, DYLAN. An Alternative Synthetic Pathway to γ-Lactam Compounds

Through the Application of Novel Reformatsky-Type Chemistry. Department

of Chemistry, June 2020

ADVISOR: James C. Adrian Jr. Ph.D.

It is the intent of the present report to relate the results of our attempt to elucidate and optimize a novel preparation of γ-lactam compounds. To achieve this end, it is proposed that the use of novel Reformatsky-type chemistry may provide a viable means. Generally, it has herein been validated that employment of α-amino ketones in traditional Reformatsky chemistry will form the traditional Reformatsky ester-adduct, and that this adduct is capable of spontaneously …

Synthesis And Characterization Of Transition Metal Scorpionate Complexes For Redox Shuttle Applications In Dye-Sensitized Solar Cells, Chase Lance

Honors Theses

Given the rising global energy demands, alternative renewable energy sources are currently being investigated. The most appealing renewable energy source is solar energy, and dye-sensitized solar cells (DSSCs) in particular are an attractive technology. DSSCs have traditionally utilized iodide/triiodide as the redox mediator couple, which exhibits high efficiencies and fast regeneration of the oxidized dye with little recombination. Recently, the use of alternative redox couples based on transition metal complexes has been studied as a promising substitute due to the tunable design of these complexes. In this study, tridentate tris(pyrazolyl)borate and tris(pyrazolyl)methane ligands with first-row transition metals were designed and …

Synthesis Of Fluorinated Pyrazoles Via Intra- And Intermolecular Cyclization Reactions, Matthew Saucier

Honors Theses

Pyrazole-based pharmaceuticals treat a wide array of diseases and conditions including obesity, diabetes, cancer, microbial and viral infections, pain and inflammation, and many neurological disorders. Syntheses for this biologically significant substrate have been well developed, but current methods to afford fluorinated pyrazoles are limited by variability and selectivity. By 2013, over 25% of all drugs available on the market contained the element fluorine due to its unique characteristics leading to improved target protein binding, bioavailability, and metabolic stability. In order to harness these pharmaceutical benefits of fluorine and overcome its difficulty in handling and stability, we set out to develop …

Silver-Catalyzed Synthesis Of Disubstituted Fluorinated Isoxazoles, Micah Stewart

Honors Theses

The presence of fluorine can provide organic compounds with useful biological properties, such as increased metabolic stability and drug uptake. Because of these advantages, fluorinated compounds make up about 30% of the drug industry. However, fluorination of complex molecules is difficult due to fluorine’s high electronegativity.

Fluorinated isoxazoles are of particular interest in the pharmaceutical industry. Isoxazoles are five-membered heterocycles with oxygen and nitrogen in the 1, 2 positions that are able to engage in interactions unavailable to other ring structures, conferring advantageous biological properties upon compounds containing them. However, there are limited synthetic routes for fluorinated isoxazoles, and those …

Preparation And Cytotoxicity Of Novel Carbon Nano-Onion Materials, Cammie York

Honors Theses

The applications of carbon nanomaterials (CNM), including graphene and its derivatives such as carbon nanotubes (CNTs) in nanomedicine is well established. These nanomaterials have been widely used as theranostic delivery systems with the potential to deliver bioactive agents and simultaneously detect selectively diseased tissues. A rather underexplored CNM for biomedical imaging and theranostics delivery are carbon nano-onions (CNOs). CNOs are carbon-based nanomaterials that can potentially be used in cancer therapy when they are functionalized. Recent studies on cellular fate of different CNMs, including CNOs, have demonstrated that the surface composition is critical for the in vivo application of these CNM. …

A Study On The Modifications Of [2.2]Paracyclophane And Their Effects On The Enantioselectivity Of The Copper Catalyzed Cyclopropanation Reaction, Yousef Dawoud

Honors Theses

The use of chiral [2.2]paracyclophane Schiff-base ligands has been shown to induce enantioselectivity in the copper catalyzed cyclopropanation of styrene with diazoesters. ¹ Previous research by Dr. Masterson tested Schiff-base ligands based on 4- amino[2.2]paracyclophane with moderate enantioselectivity. In this project, the Schiff-base N- salicylidene-4-amino[2.2]paracyclophane, was modified by way of Grignard addition to the imine carbon and its enantioselective properties were explored with the copper catalyzed cyclopropanation. The methyl Grignard addition to N- salicylidene-4-amino[2.2]paracyclophane was successful in producing the amino alcohol and the amino alcohol was characterized. The amino alcohol was produced from the R enantiomer of the Schiff-base and …

Best Organic Chemistry Practices In The Midwest, Claire Van Der Bosch

Honors Theses

Organic Chemistry is a gateway course to a handful of courses in higher chemical education. Unfortunately, it is notorious for its high-fail, high-withdrawal, and high-drop rate and has a reputation for being time-consuming, with difficult concepts that are oftentimes new to students. It is often taught in a two-semester sequence, with the courses named Organic I and Organic II, and both courses have a lab component. At Western Michigan University, the fail rate for these two courses are 53.5% and 36.9%, respectively. Most higher education institutions are certified with the American Chemical Society (ACS) and given a skeleton of a …

Analysis Of Dl-Amino Acid Ratios In Eggshells Using Reverse Phase-High Pressure Liquid Chromatography, Gergana Milkova

Honors Theses

HPLC methodology was developed to determine the concentrations and ratios of D to L amino acids in emu and ostrich eggshells treated with heat at different temperatures . We aimed to determine an internal standard and how ratios were affected under different conditions. An HPLC method was determined that gave consistent retention times and satisfactory enantioseparation . Calibration curves for each amino acid were developed from single and multi-amino acid containing dilution series producing a model that most closely replicates the eggshell-extracted amino acids.

Generation And Reactions Of Cyclopropyl Vinylidene Carbenes, Nguyen Nhat Thu Le

Honors Theses

This study aimed to generate cyclopropyl methyl vinylidene carbene and cyclopropyl phenyl vinylidene carbene via photochemical routes. The precursors to these two carbenes were synthesized from phenanthrene by a two-step procedure. However, these precursors could not be fully purified because the second step generated many side products with similar properties as the precursors. A crude sample of each precursor were photolyzed with UV light in the range of 315 to 400 nm. Vinylidene carbenes are known to rapidly rearrange into alkynes, so the formation of these cyclopropyl vinylidene carbenes was monitored through the formation of their rearrangement products, cyclopropyl methyl …

An Exploration Of Pyrrole Groups On The Enantioselectivity Of Pig Liver Esterase, Brian Long

Honors Theses

Pig Liver Esterase (PLE) is a serine protease enzyme that can interact with one side of a diester to hydrolyze the ester to a carboxylic acid, and research has found that the level of hydrophobicity of side groups can impact the enantioselectivity of PLE hydrolysis.1, 2 The Jones Model is what current researchers use to model the active site of PLE, but the nature of its binding pockets, namely the Hydrophobic Long (HL) pocket, has been called into question.3 Dimethyl 2-((pyrrole-2-yl)methyl)-2-methylmalonate was prepared to be subjected to PLE hydrolysis to see whether enantioselectivity was found. Chiral HPLC revealed 25.32% enantiomeric …

Treating Breast Cancer With Light: The Creation Of Two Photodynamic Therapy Agents, Victoria Lackey

Honors Theses

Photodynamic therapy (PDT) is a treatment for a wide display of diseases, including cancer, that has become gradually widespread. The procedure requires the usage of photosynthesizing agents, which are activated in the presence of light. One quite successful photodynamic therapy agent is an aromatic structure made up of four pyrrole rings called a porphyrin. This research focused on producing the water-soluble porphyrins, H2TPP-3-PEG-OH and H2TPP-PiperMe-OH, through the attachment of the starting porphyrin, H2TPPC, with 3-polyethyleneglycol and 3-piperidinemethanol, respectively. The novel, water-soluble agent was purified and characterized by infrared spectroscopy (IR), nuclear magnetic resonance spectroscopy (NMR), and UV-vis spectroscopy. Purity was …

Diastereoselective Synthesis Of 2,4,6-Trisubstituted Piperidines Via Aza-Prins Cyclization, John A. Hood

Honors Theses

The nitrogen heterocycles are shared amongst 59% of Food and Drug Administration (FDA) approved small molecule pharmaceuticals with the six-membered piperidine representing the most common moiety. Given the versatility and potential to yield derivatives with broad biological activities, the discovery of new chemical methods to generate these heterocycles in a more time and cost-efficient manner is desired. While there are existing racemic methods to access this class of molecule, the objective of this research is to pioneer a new novel six-step method to generate 2,4,6-trisubstituted piperidines with stereoselective control.

The first step is a condensation between a nonenolizable aldehyde and …

Silicon And Tin Substituted Halocyclopropanes: Approaches To New Carbenes And Strained Cyclic Allenes, Noura Srour

Honors Theses

Chloro(trimethylsilyl)carbene and chloro(trimethylstannyl)carbene were generated through photolysis of cyclopropanated phenanthrene precursors which were synthesized in two steps. The photolysis reactions were done in the presence of cis and/or trans-beta-methylstyrene. Though product peaks corresponding to the carbene-alkene adducts were observed in the GCMS, the yields were too low for their isolation and complete characterization. Density functional theory (DFT) calculations were performed on the stereoisomers of the precursor to Chloro(trimethylsilyl)carbene and the carbene itself. Surprisingly, Chloro(trimethylsilyl)carbene’s triplet state was found to be more stable than the singlet at this level of theory.

In a related project, (1-bromo-1a,9b-dihydro-1H-cyclopropa[l]phenanthren-1-yl)trimethylstannane, was …