Polycyclic Compounds Commons^™

Phytochemical And In-Vitro Cytotoxic Analyses Of Flavonoid Species Isolated From Chromolaena Leivensis, Luke A. Bryant

Electronic Theses and Dissertations

As a leading cause of death worldwide, cancer and its treatments remain a primary source of interest among researchers. Modern studies are looking into bioselective cytotoxicity to create new chemotherapies that do not have the same harsh side effects as those we use today. Natural product research has a promising future for the development of such treatments. Specifically, polar flavonoids may be the key to a bioselective treatment. Such flavonoid species are native to plants, often within flower petals or within the body. A natural antioxidant, they are designed not to harm healthy cells. This study focuses on the plant …

Quantifying Black Carbon Concentrations In Georgia And Analyzing Associated Public Health Risks, Khloe R. Osborne

Honors Theses

Quantifying Black Carbon Concentrations in Georgia and Analyzing Associated Public Health Risks

One of the most daunting challenges of the industrial world is air pollution. Within this broad spectrum, there is an inhalable particle group named PM2.5, which contains black carbon. Black carbon has evidence that supports the generation and worsening of adverse health impacts, which may include birth complications, cognitive deficits in children, pulmonary aggravation, asthma, cardiovascular issues, neurological degenerative patterns, and cancer risk. This is especially seen in vulnerable populations, like children, elderly, and those who already suffer from weakened health, many of which reside in the southern …

The Influence Of Fermentation Duration And Secondary Fermentation Conditions On The Bioactive Compound Profile Of Kombucha, Jordan Vereen

Honors Theses

Kombucha is a fermented sweet tea produced using a symbiotic culture of bacteria and yeast (SCOBY) and has gained widespread popularity due to its proposed health benefits. Kombucha has been studied to understand these advantages in cardiovascular support, improved metabolism, increased antioxidant effects, enhanced antimicrobial properties, and even potentially slowing the progression of certain diseases. Despite its increasing popularity, the way in which the specific bioactive compounds responsible for these effects and the fermentation conditions that influence their production remain unclear. The present study, conducted in collaboration with Dr. Budner, focuses on quantifying bioactive compounds in kombucha to better understand …

Development Of Tunable Rose Bengal Based-Nanogumbos As Potential Selective Chemotherapeutic Agents, William J.A. Russell

Honors College Theses

As cancer remains one of the greatest threats to the global population, the development of chemotherapeutic agents that are selective and tunable is of critical importance. Herein, a series of Rose Bengal (RB)-based GUMBOS, a group of uniform materials based on organic salts, were synthesized via counterion exchange between [Na]₂[RB] and three organic cations: tetrabutylphosphonium bromide [TBP][Br], tetraphenylphosphonium chloride [TPP][Cl], and 1-dodecyl-3-methylimidazolium chloride [C₁₂MIm][Cl]. The resulting GUMBOS were characterized through FT-IR, ESI-MS, NMR, and UV-Vis Spectroscopy. Partition coefficient studies indicated all GUMBOS exhibited hydrophobic physiochemical characteristics. These hydrophobic RB-based GUMBOS …

Advances In Indole Chemistry: Regiodivergent Annulations And Bridged Azacycle Synthesis, Zachary Tihomir Protich

Dartmouth College Ph.D Dissertations

An important aspect for the research and development of new drug therapies is the ability to use modular synthetic methods to rapidly access structurally diverse drug-like building blocks. Nitrogen-containing heterocycles represent one of the most prevalent structural motifs found in pharmaceutical agents and biologically active natural products. However, despite their ubiquity, existing methods for accessing these structures often remain limited in scope, efficiency, and structural diversity, particularly when targeting densely functionalized or sterically demanding scaffolds from simple starting materials.

To address this problem, the research described in this dissertation focuses on the design and development of (3+2) annulation reactions for …

Novel Piperidone And Bispidine Derivatives: A New Approach In Cancer Therapy, Lereen Khaled Youssry

Theses and Dissertations

Cancer remains the second leading cause of death worldwide. As a result, scientists have been trying to find novel therapeutic approaches that target specific metabolic pathways selective to tumor cells. In this study, two novel piperidone and bispidine derivatives, organic molecules that target polyamine metabolism, were synthesized, and their potential cytotoxic, antioxidant and anti-inflammatory effects were investigated. Polyamines are naturally occurring metabolites that were reported to be in excess at cancer cells and were accounted for tumor proliferation, invasion and metastasis. Accordingly, the novel piperidone and bispidine derivatives were expected to disrupt tumor growth and progression via up-regulation of key …

Synthesis Of Small Molecules As Therapeutic Candidates, Savia Boyer

Electronic Theses & Dissertations (2024 - present)

RNA plays a critical role in many biological functions, such as normal cellular functions or disease-related processes. Regulating biological processes through RNA-based therapeutics can be employed by the reversible photoregulation of oligonucleotides. Azobenzene, a light-responsive compound that changes conformation when exposed to ultraviolet (UV) or visible light, is attached to cytidine phosphoramidite to be incorporated in a series of RNA oligonucleotides. The reversibility of the nucleoside and oligonucleotide is verified through UV melting point experiments. The modified oligonucleotide can change conformation upon light irradiation to stop reverse transcription (RT) in the presence of many different reverse transcriptase enzymes. This technique …

Effects Of Modification In Limonene And Geraniol On The Properties Of Thermal Cured Polyurethane Films, Sauravkumar Rajeshbhai Patel

Electronic Theses & Dissertations

The increasing demand for green materials has inspired in-depth research into biobased polymers; among these polymers, polyurethanes stand out because of their widest range of applications: coatings, adhesives, and biomedical devices. The subject of this paper is the preparation of bio-based polyurethane films based on the polyols synthesized from renewable feedstocks such as limonene, geraniol, and soybean oil. Limonene and geraniol were chemically modified from natural sources such as citrus fruits and essential oils to high-functionality polyols. Characterization of such polyols showed that geraniol had the highest hydroxyl (OH) value and thus geraniol-based polyurethane films were highly influencing in reactivity …

Design, Synthesis, And Nmr-Guided Characterization Of A Targeted Covalent Inhibitor-Like Molecule Against Ivyp1 From P. Aeruginosa, Samuel Taylor Moore

Master's Theses

Multi-drug resistance poses a serious threat to future generations and historical antibiotic pipelines; consequently, the medical and economic burdens associated with treating multidrug-resistant bacteria are substantiated. In this context, P. aeruginosa (PA) emerges as one of the most significant healthcare challenges, being a leading cause of resistance-associated mortality worldwide. Despite modern efforts to combat these poor outcomes, drug-resistant cases continue to rise, and the need for novel antibiotic treatment is apparent. To this end, we investigated relevant resistance mechanisms and past antibiotic targets within PA, and in doing so, we identified relationships between peptidoglycan biology and a periplasmic protein, Inhibitor …

Synthesis Of Photocleavable Molecules For Neurological Applications, Nishal Madujith Egodawaththa Arachchilage Don

Theses and Dissertations

In recent biomedical research, the precise control of molecular dynamics through light activation has emerged as a powerful tool, particularly in the field of neurobiology. This approach involves the use of photocleavable cages or photoprotective groups (PPGs) that are chemically tethered to biologically active molecules such as neurotransmitters or calcium chelators. These cages remain inert until exposed to specific wavelengths of light, typically in the visible range, triggering the release of the active compound with high spatiotemporal precision.

For neurotransmitter systems, such as glutamate (Glu), which plays a critical role in synaptic transmission and memory formation, researchers have developed novel …

Benzo[A]Pyrene-Induced Multigenerational Gene Expression And Dna Methylation Changes Are Influenced By Paternal Epigenome, Caroline Sturgis

Honors Theses

The objectives of this study were to determine the sex-dependent contributions to developmental and behavioral effects of preconceptional exposure to benzo[a]pyrene (BaP). BaP is implicated in numerous adverse outcomes in offspring of exposed parents, but the molecular mechanisms for the developmental and multigenerational effects associated with BaP exposures have yet to be fully elucidated. To assess the role of the aryl hydrocarbon receptor (Ahr), a waterborne exposure of the offspring of ahr heterozygous (ahr^+/-) parents was conducted. At 120 hpf, BaP treated fish moved significantly less in the dark phase regardless of genotype. At 3 wpf, there …

Advancing Small Molecule Therapies For Myotonic Dystrophy Type 1, Sawyer M. Hicks

Electronic Theses & Dissertations (2024 - present)

Myotonic dystrophy type 1 (DM1) is a multisystemic disorder caused by the expression of expanded CUG (CUG^exp) repeat RNA from the myotonic dystrophy protein kinase (DMPK) gene. This CUG^exp repeat RNA’s gain-of-function mechanism leads to the sequestration of muscleblind-like (MBNL) proteins, resulting in widespread alternative splicing dysregulation across tissues. Despite significant research, there are currently no approved therapeutics targeting the underlying causes of DM1. This dissertation explores the development and optimization of a novel class of small molecules, Modified Polycyclic Compounds (MPCs), designed to address splicing dysregulation in DM1. MPCs were designed from previously published …

Effects Of Environmental Pollutants On Liver Disease: Role Of The Gut-Liver Axis., Ngozi Victoria Adiele

Electronic Theses and Dissertations

Polychlorinated biphenyls (PCBs) and polystyrene (PS) microplastics are environmental pollutants associated with various diseases including toxicant associated fatty liver disease (TAFLD). Previously, exposure to Aroclor 1260 (a PCB mixture) has been shown to exacerbate TAFLD, partly through Aroclor 1260 induced gut dysbiosis. Studies has also demonstrated that PS exposure alters gut microbiome composition and induced obesity. However, the effects of Aroclor 1260 on the gut and the effects of PS on the liver are still understudied. Therefore, we hypothesize that environmental pollutants will disrupt the gut-liver axis through changes in gut and its microbiome as well as changes in liver …

Photodynamic Therapy To Treat Triple Negative Breast Cancer In Vitro, Hunter S. Warren

All Theses

Triple negative breast cancer (TNBC) is the most resilient form of breast cancer, being one of the leading causes of death for women and making up 7% of all cancer deaths. Photodynamic therapy (PDT) offers a minimally invasive solution to TNBC as a passive-targeting treatment that reduces the need for other well established yet harsh treatments that can be taxing on the patient. PDT involves the use of a high-energy red light on the area of a tumor injected with photosensitizers (PS) that generate reactive oxygen species (ROS) in the tumor, triggering cell death. The PS tetra(hydroxyphenyl)chlorin (m-THPC) was used …

Design, Synthesis, Biological And Computational Studies Of Flavonoid Acetamide Derivatives, Daniel Kasungi Isika

Dissertations

Flavonoid compounds (FC) have extensive biological applications through potent antimicrobial, anti-inflammatory, anticancer, antidiabetic, and antioxidant properties. These applications are nevertheless limited by low bioavailability, poor aqueous solubility, enzymatic degradation, rapid metabolism, and fast body clearance. FC show unique structure-activity relationships (SARs) essential in assessing and mitigating the prevalent challenges impeding their applications. These challenges can be addressed by structural modification of the FC through functionalization of the phenolic rings, modification of the ketone group, and modification of the phenolic hydroxyl groups with bioisosteres.

The objectives of this work are to (i) design and synthesize novel flavonoid acetamide derivatives (FADs) and …

Photodynamic Therapy Agents: The Power Of Mjöllnir To Eradicate Cancer, Sidney M. Hopper

Honors College Theses

After its discovery back in the 1900s, photosensitizers became a critical study for potential treatments and cures for medical issues, including cancer. It was discovered that porphyrins appeared to target and accumulate in proliferating cells, and to reach the cells, a certain wavelength of light with maximum absorbance associated with the porphyrin was necessary to achieve cell death. Photodynamic therapy involves making use of porphyrins or metalloporphyrins as activators when exposed to such light. When activated, these compounds generate reactive oxygen species (ROS), such as HO- or O2-, which can react with nucleic acids found in DNA and RNA. In …

Examining The Oxidative Stress Effects In Rats Exposed To 2-Aminoanthracene In Utero And High Fat Diet Three Months After, Brianna A. Lanoix

Honors College Theses

Polycyclic aromatic hydrocarbons are organic compounds that are created synthetically or found in partially burned oil, gasoline, and coal. 2-aminoanthracene (2AA) is a common example of a PAH and can affect lipid and carbohydrate metabolism and resulting in inflammatory problems and oxidative stress. The objective of the research project is to investigate oxidative stress in relation to diabetes in rats exposed to 2AA in utero and a high fat diet later in life. Pregnant dams were separated into treatment groups based on their dosages of 2AA; 0 mg/kg (control), 50 mg/kg (low), 100 mg/kg (high). During the gestation -postpartum period, …

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 …

Effects Of Waterborne Benzo[A]Pyrene Embryonic Exposure On Development, Behavior, Reproduction, And Mitochondrial Bioenergetics In Zebrafish, Megha Patel

Honors Theses

Benzo[a]pyrene (BaP) is a polycyclic aromatic hydrocarbon (PAH) that is a known carcinogen leading to adverse effects in the development of both humans and animals. BaP is also continuously present in the environment leading to regular exposure via inhalation or ingestion. Because organisms’ early life stages can be more susceptible to contaminant exposure, our focus was on BaP’s adverse impacts on survival, length, weight, behavior, bioenergetic state, and fecundity following developmental exposures. To study BaP’s impacts, zebrafish (Danio rerio) were used as a model organism. BaP is a ligand for the aryl hydrocarbon receptor (AHR in humans; Ahr in …

Molecular Dynamics Simulations Of Self-Assemblies In Nature And Nanotechnology, Phu Khanh Tang

Dissertations, Theses, and Capstone Projects

Nature usually divides complex systems into smaller building blocks specializing in a few tasks since one entity cannot achieve everything. Therefore, self-assembly is a robust tool exploited by Nature to build hierarchical systems that accomplish unique functions. The cell membrane distinguishes itself as an example of Nature’s self-assembly, defining and protecting the cell. By mimicking Nature’s designs using synthetically designed self-assemblies, researchers with advanced nanotechnological comprehension can manipulate these synthetic self-assemblies to improve many aspects of modern medicine and materials science. Understanding the competing underlying molecular interactions in self-assembly is always of interest to the academic scientific community and industry. …

Analysis Of Multigenerational Behavioral Effects Of Dietary Benzo[A]Pyrene Exposure In Adult Zebrafish, Mary Beth Gillespie

Honors Theses

Benzo[a]pyrene (BaP) is a polycyclic aromatic hydrocarbon that is linked to negative reproductive and developmental effects in humans and animals. Because BaP is carcinogenic, and its continued presence in the environment allows it to be inhaled and ingested, better understanding of the effects of BaP is needed. To determine the behavioral effects of BaP exposure, zebrafish were used as a model. Wild-type zebrafish (5D) underwent two separate 21-day dietary exposures to 2.5 and 25 μg BaP/g fish to compare how BaP exposure affects locomotor activity. Following the dietary exposure, fish were mated to obtain and raise the F1 generation to …

Applied Molecular Dynamics: From Targeting Viral Helicases, To Understanding The Interactions Of Cucurbituril Complexes In Ionic Solutions, Bryan Raubenolt

LSU New Orleans Theses and Dissertations

Molecular Dynamics simulations are a highly useful tool in helping understand the fundamental interactions present in a variety of chemical systems. The work discussed here illustrates it’s use in determining the conformational dynamics of the Zika and SARS-Cov-2 helicase in a physiological environment, largely in an effort to discover inhibitors capable of rendering the protein inert. Additionally, we show how it can be used to understand paradoxical trends in the anion-induced precipitation of Cucurbituril cavitands.

Viral helicases are motor proteins tasked with unwinding the viral dsRNA, a crucial step in preparing the strand to be translatable by host cells. By …

Fluorometric Characterization Of A Methylene Blue Derivative Sensitive To Reactive Oxygen Species (Ros), Matthew Weeks

Honors Theses

Methylene blue (MB) has many uses within both microbiology and pharmacology. MB can treat disorders such as methemoglobinemia, malaria, Alzheimer’s disease, and certain forms of cancer. MB is also useful for molecular imaging due to its off-on fluorescent capabilities. MB derivatives with a urea bond at the 10-N position have been cleavable by triggers such as light. However, I was interested in sensitivity to reactive oxygen species (ROS). In this study, I wanted to determine if the MB derivative MB-EA exhibited sensitivity to ROS. MB-EA was exposed to varying concentrations of hydrogen peroxide and MB release was measured. I concluded …

Catalyzed And Uncatalyzed Modifications Of Nucleosides, Synthesis Of Hippadine, And Deuterated 1,2,3-Triazoles, Hari K. Akula

Dissertations, Theses, and Capstone Projects

The C4 amide carbonyl of O-t-butyldimethylsilyl-protected thymidine, 2’-deoxyuridine, and 3’-azidothymidine (AZT) was activated by reaction with (benzotriazol-1-yloxy)tris(dimethylamino) phosphonium hexafluorophosphate (BOP) and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in THF as solvent. This led to the formation of corresponding O⁴-(benzotriazol-1-yl) derivatives, which are reactive intermediates. Substitution at the C4 position was then carried out by reactions with alkyl and aryl amines, and thiols. Typically, reactions were conducted as a two-step, one-pot transformation, and also as a one-step conversion. After examining the reactions, the formation of 1-(4-pyrimidinyl)-1H-benzotriazole-3-oxide derivatives from the pyrimidine nucleosides was identified. However, these too underwent conversion to …

Diversity Oriented Synthesis, Characterization And Anti-Cancer Activity Of Killer Peptide Nucleolipid Bioconjugates, Niki K. Rana

Seton Hall University Dissertations and Theses (ETDs)

The killer peptide sequence D-(KLAKLAK)₂ has been originally designed and developed as an antibacterial agent. Despite having excellent cytotoxicity towards bacteria, this sequence maintains low cell cytotoxity in malignant mammalian cell types such as cancer. The chemical basis for its selectivity has been attributed to its poly(cationic) amphiphilic nature, which facilitates cell permeability across the negatively charged bacterial membrane, but with limited permeability across the zwitterionic membrane of mammalian cells. The positively charged D-(KLAKLAK)₂ sequence has been found to accumulate on the surface of the mitochondria causing dissipation of the negatively charged mitochondrial membrane potential. This charge disruption …

Synthesis Of Oxadeazoles With Electron Withdrawing Groups And The Analysis Of Product Yield With Bond Length, Elizabeth Ann Hall Peters

Undergraduate Honors Thesis Projects

2,5-disubstituted 1,3,4-oxadiazoles are a class of organic compound that are widely used and successful in pharmaceutical chemistry because they demonstrate strong biological activity. They are part of a larger class of compound called heterocycles, which make up most pharmaceutical drugs today. When synthesizing the compounds, higher yield means higher reactivity of the compound, and this is important for pharmaceuticals that need to have a strong biological activity. Per past studies, electron withdrawing groups on the compound allow higher, product yields. Along with electron withdrawing group addition, the bond length from electron withdrawing group and its corresponding carbon is analyzed to …

Chemoselective And Stereoselective Exploration Of The Chemical Reactivity Space Of Castagnoli-Cushman-Derived Allylic Lactamoyl Esters: Application To The Synthesis Of Aza-Polycyclic Architectures, Brandon Joseph Mansker

All Master's Theses

The synthesis and evaluation of structure-activity relationships of saturated nitrogen heterocycles is the focal point of various pharmaceutical companies thanks to the high biological activity of previously isolated azacycles. Here, we describe an operationally simple and highly efficient approach to macrocyclic lactams bearing vicinal stereocenters and a challenging cycloalkyne motif. The outcomes are achieved through a novel [4 + 2] cycloaddition reaction between an N-iodoarylated-1,3-azadiene and cyclic anhydrides, followed by interception of the cycloadducts in cross-coupling manifolds (e.g., Sonogashira coupling) and concomitant lithiation-cyclization of the tethered alkyne. An unprecedented example of a hydroamino alkylation that is transition …

A Diversity-Oriented Synthesis Approach To Functionalized Azaheterocycles Using Cyclic Alpha-Halo Eneformamides, Spencer A. Langevin

All Master's Theses

Functionalized piperidines, azepanes, azamacrocycles, morpholines, and thiomorpholines are common structural motifs found in a wide range of pharmaceuticals such as carmegliptine, levofloxacin, thioridazine, claviciptic acid, and azithomycin. As a result, there is a strong desire to construct highly functionalized nitrogen-bearing ring scaffolds in order to construct a wide range of drug possibilities. There are several non-modular and step-uneconomical synthetic methods used in the construction of these aforementioned motifs such as ring closing metathesis, ring expansions, and intramolecular reductive amination. In this research, we present a step-economical, cost-effective, scalable, and diversity-oriented synthesis approach to highly functionalized N-heterocycles through the intermediacy of …

Target-Directed Biosynthetic Evolution: Redirecting Plant Evolution To Genomically Optimize A Plant’S Pharmacological Profile, Dustin Paul Brown

Theses and Dissertations--Neuroscience

The dissertation describes a novel method for plant drug discovery based on mutation and selection of plant cells. Despite the industry focus on chemical synthesis, plants remain a source of potent and complex bioactive metabolites. Many of these have evolved as defensive compounds targeted on key proteins in the CNS of herbivorous insects, for example the insect dopamine transporter (DAT). Because of homology with the human DAT protein some of these metabolites have high abuse potential, but others may be valuable in treating drug dependence. This dissertation redirects the evolution of a native Lobelia species toward metabolites with greater activity …

Antibiotics That Inhibit 30s Or 50s Ribosomal Subunit Formation: Hygromycin B, Quinupristin-Dalfopristin And Xrp 2868., Susan Mabe Mcgaha

Electronic Theses and Dissertations

Several antibiotics that prevent translation by binding to ribosomal subunits have been shown to also inhibit ribosomal subunit assembly (Champney and Tober 2003). The aminoglycoside hygromycin B was examined in Escherichia coli cells for inhibitory effects on translation and ribosomal subunit assembly. The streptogramin antibiotics quinupristin-dalfopristin and XRP 2868 (NXL 103) were examined for similar effects on these 2 cellular functions in antibiotic-resistant strains of Haemophilus influenzae, Staphylococcus aureus, and Streptococcus pneumoniae.

Pulse chase experiments were performed which verified slower rates of ribosomal subunit formation in drug treated cells. Hygromycin B exhibited a concentration dependent inhibitory effect …