CHEM2026RANGEL12559 CHEM
Type: Graduate
Author(s):
Andrea Rangel
Chemistry & Biochemistry
Advisor(s):
Eric Simanek
Chemistry & Biochemistry
Location: SecondFloor, Table 9, Position 3, 11:30-1:30
View PresentationChemotherapy relies on two therapeutic paradigms. The classic approach, most often used, employs small molecules to specifically target enzyme active sites, as represented by the new generation of kinase inhibitors. A secondary approach relies on interfering with protein-protein interactions thus requiring the use of larger compounds. While this latter strategy is garnering the attention of the pharmaceutical community, the rules for the design of these larger molecules, which are often cyclic, are not understood. The compact shape of small molecules leads to predictable behaviors including oral availability and cell uptake. For larger molecules that adopt multiple shapes, understanding the factors that control their shape and dynamic motion provides opportunities to predict similar behaviors that are critical for rational drug design. Here, the synthesis and characterization of a library of large, cyclic molecules (macrocycles) is described. The macrocycles of interest result from the dimerization of monomers. A total of 50 monomers containing different drug-like groups were synthesized. Reaction of a single monomer yields a homodimer, while combination of two different monomers leads to a 1:1:2 mixture of homodimers and a heterodimer. These combinations ultimately lead to a library of 1,275 different compounds. Liquid chromatography-mass spectrometry confirms that >99.9% of the reactions were successful. To investigate the biological activity of these compounds, we have provided this library to high throughput drug-screening facilities at Vanderbilt University and Scripps Florida. Of the several compounds created, macrocycles containing hydroxylamine groups are of special interest for two reasons. First, these molecules are similar to Hydrea, a widely-used, FDA-approved cancer drug. Second, unlike most macrocycles, both the shape and dynamics of these molecules are well understood so critical parameters such as oral availability and membrane transit can be predicted.
CHEM2026SAYEGH24495 CHEM
Type: Undergraduate
Author(s):
Mark Sayegh
Chemistry & Biochemistry
Katie Smith
Chemistry & Biochemistry
Advisor(s):
Kayla Green
Chemistry & Biochemistry
Location: SecondFloor, Table 4, Position 3, 11:30-1:30
View PresentationReactive oxygen species (ROS) are byproducts of normal cellular metabolism and play important roles in cell signaling and immune defense. However, when their production exceeds the cell’s antioxidant capacity, ROS accumulation leads to oxidative stress, damaging proteins, lipids, and DNA. In the brain, this oxidative imbalance has been closely linked to the development and progression of neurodegenerative diseases like Alzheimer’s. Under normal conditions, superoxide dismutase (SOD) enzymes play a key role in protecting cells by breaking down harmful superoxide radicals. Yet, reduced SOD activity and impaired regulation have been consistently observed in patients with neurodegeneration, including Alzheimer’s disease. Small-molecule mimics of SOD, therefore, represent a promising therapeutic approach. In this study, we evaluate an expanded library of tetra-aza macrocyclic ligands chelating either copper or manganese metals. Mechanistic analysis reveals how structural modifications to the macrocyclic ring, particularly R-group substitutions that alter steric environment and electronic properties, directly influence catalytic reactivity and stability. Evaluation of Cu- and Mn-based complexes highlights distinct trends in activity and identifies structural motifs that enhance SOD-like function. These findings provide design principles for developing antioxidant therapeutics targeting oxidative stress.
CHEM2026TRAN56990 CHEM
Type: Undergraduate
Author(s):
Jeremiah Tran
Chemistry & Biochemistry
Advisor(s):
Youngha Ryu
Chemistry & Biochemistry
Location: SecondFloor, Table 5, Position 3, 11:30-1:30
View PresentationRiboswitches are structured RNA elements that regulate gene expression through ligand-induced conformational changes and provide a platform for engineering cell-based biosensors. By coupling aptamers to reporter genes, synthetic riboswitches enable small-molecule–dependent detection of clinically relevant metabolites. This study focuses on sarcosine, associated with prostate cancer progression, and urate, linked to gout. Two sarcosine-responsive candidates were evaluated in E. coli using β-galactosidase and GFP reporter systems. Although construct integrity was confirmed, neither candidate demonstrated ligand-dependent activation in CDR or minimal media, suggesting insufficient regulatory activity under tested conditions. In parallel, a urate-responsive riboswitch library underwent dual selection with chloramphenicol resistance for positive selection and 5-fluorouracil counterselection for negative selection. After multiple selection rounds and screening of 192 colonies, no urate-specific variants were identified. Increasing chloramphenicol concentration to strengthen positive selection similarly yielded no hits. Future work will focus on further increasing both positive and negative selection intensity to enhance enrichment of functional variants and improve development of RNA-based biosensors for accessible metabolite detection. Additionally, future efforts will explore the adenine riboswitch library as a potential platform for developing novel biomarker detection systems.
CHEM2026WALLS5028 CHEM
Type: Graduate
Author(s):
Caden-Jack Walls
Chemistry & Biochemistry
Kayla N. Green
Chemistry & Biochemistry
Benjamin Janesko
Chemistry & Biochemistry
Advisor(s):
Kayla Green
Chemistry & Biochemistry
Location: SecondFloor, Table 6, Position 1, 11:30-1:30
View PresentationNitric oxide (NO) is a gaseous free-radical 2° messenger with a physiological half-life of 3-5 seconds. Overexpression of the cytoprotective NO can lead to high concentrations of cytotoxic peroxynitrite (OONO^-), causing nitroxidative stress. Studies have shown that nitroxidative stress can be implicated as an etiology of several inflammatory diseases, such as Alzheimer’s Disease (AD) or Parkinson’s Disease (PD). A solution to counter nitroxidative stress is the biomimicry of the enzyme Nitric Oxide Dioxygenase (NOD). The enzymic activity of NOD relies on a heme active site, where excess NO is scavenged to produce nitrate (NO_3^-), a less potent oxidant. Several groups have successfully mimicked this activity; however, it has been restricted to water-insoluble, large molecules (porphyrin rings). While other antioxidant enzymes such as Superoxide Dismutase and Catalase have been successfully mimicked with water-soluble, metal-centered, non-heme scaffolds, to date, there have been no reports of water-soluble non-heme mimics of NOD activity. It is the Green Group’s goal to explore the possibility of developing a molecule capable of NOD enzymic activity. Therefore, theoretical feasibility of this reaction was explored using Density Functional Theory (DFT) as well as Conformer-Rotamer Ensemble Sampling Tool (CREST). Current data shows that based on an energy screening of several simple-to-complex tetra-aza small molecules, the reaction is successful both in gas phase and in water (implicit and explicit solvation). Additionally, computational intermediate spin states have, so far, matched those reported experimentally. Energy diagrams were then proposed based on the most stable ground state energies of structural intermediates. This data provides, for the first time, a new perspective on the possibility of the successful biomimicry of NOD with non-heme, water-soluble, tetra-aza small molecules.
CHEM2025AFROZ17453 CHEM
Type: Graduate
Author(s):
Tahmina Afroz
Chemistry & Biochemistry
Advisor(s):
Kayla Green
Chemistry & Biochemistry
Location: SecondFloor, Table 7, Position 3, 1:45-3:45
View PresentationDIRECT ARYLATION OF UNACTIVATED ARENE USING EARTH ABUNDANT IRON/TETRA-AZA MACROCYCLIC COMPLEX
The development of sustainable catalytic systems for carbon–carbon bond formation is of critical importance in modern synthetic chemistry. This study presents an iron-based catalytic system employing tetra-aza macrocyclic ligands as a cost-effective and environmentally benign alternative to palladium in direct arylation reactions. Using [Fe²⁺L6(Cl)₂] as the catalyst and molecular oxygen as the terminal oxidant, the direct C(sp²)–C(sp²) coupling of pyrrole with substituted phenylboronic acids was achieved under mild conditions, yielding 2-phenylpyrrole and its derivatives with moderate efficiency (up to 62%). The catalyst displayed broad substrate scope and functional group tolerance, effectively accommodating halogen, nitro, alkyl, and methoxy substituents. Mechanistic studies excluded a radical-mediated pathway and instead supported a non-radical oxidative mechanism involving an iron(III)-hydroperoxo intermediate. These findings underscore the potential of earth-abundant iron complexes in sustainable cross-coupling chemistry and set the stage for further exploration in heterocycle functionalization and pharmaceutical scaffold development.
CHEM2025ANJUM34125 CHEM
Type: Undergraduate
Author(s):
Saba Anjum
Chemistry & Biochemistry
David Mingle
Chemistry & Biochemistry
Shrikant Nilewar
Chemistry & Biochemistry
Advisor(s):
Kayla Green
Chemistry & Biochemistry
Location: Basement, Table 1, Position 1, 11:30-1:30
View PresentationAlzheimer’s disease is characterized by dysregulated production of reactive oxygen species (ROS), driving oxidative stress and subsequent neuronal degeneration. Antioxidant enzymes such as superoxide dismutase (SOD) play a central role in maintaining redox homeostasis; however, their activity is compromised in individuals with Alzheimer’s disease. Although small molecules have been developed in the past to mitigate oxidative stress, their clinical translation has been limited by poor blood-brain barrier permeability and suboptimal drug-like properties. In this work, we present a multi-step synthetic strategy for a pyridine-based tetra-aza macrocycle designed to improve blood–brain barrier permeability while retaining multi-target antioxidant activity.
CHEM2025BOBO53407 CHEM
Type: Undergraduate
Author(s):
Grace Bobo
Chemistry & Biochemistry
Liam Claton
Chemistry & Biochemistry
Advisor(s):
Eric Simanek
Chemistry & Biochemistry
Location: Third Floor, Table 10, Position 1, 11:30-1:30
View PresentationThe shape of a drug will determine how it interacts in the body. For it to work, it must dissolve, be absorbed into the bloodstream, avoid breakdown, enter the cell and bind to its target. Each of these steps likely requires a different shape. The pharmaceutical industry has historically only focused on the shape required to bind the target. This research has identified molecules that can readily adopt multiple shapes. These ring-shaped molecules (called macrocycles) represent a new model for drug design. Usual drugs (ie ibuprofen) are small and interact with a specific target to stop a chemical reaction. Macrocycles can work by an additional mechanism. They are larger and can interfere with interactions between proteins but are still small enough to travel the body. The preparation of these macrocycles is inexpensive and quick, properties that are important for the pharmaceutical industry. This poster describes the design and synthesis of a macrocycle and an analysis of the shapes that it adopts.
CHEM2025CHOUTEAU33975 CHEM
Type: Undergraduate
Author(s):
Luke Chouteau
Chemistry & Biochemistry
Advisor(s):
Kayla Green
Chemistry & Biochemistry
Location: Third Floor, Table 5, Position 3, 11:30-1:30
View PresentationEvery 65 seconds, someone develops Alzheimer's disease, which is the seventh leading cause of death in the United States. A major barrier to potential therapeutics is the permeability of these molecules across the blood-brain barrier. We have developed small molecules with strong reactivity to combat the oxidative stress known to cause Alzheimer’s disease. However, the permeability is less than ideal. As a result, my goal is to produce a molecule that has enhanced permeability but retains the reactivity of the parent molecules. To achieve this, the BOILED-Egg model assessed different derivatives of our parent molecule, Py2N2. This model showed the differences in lipophilicity among different Py2N2 compounds and how they impact permeability into the blood-brain barrier and gastrointestinal tract. Background information on our parent molecule and its function regarding Alzheimer's development will be outlined to give a scope of what these compounds can target and how they function. Compounds with high lipophilicity reflected in the model will have schemes of synthetic synthesis for future directions.
CHEM2025CLATON60165 CHEM
Type: Graduate
Author(s):
Liam Claton
Chemistry & Biochemistry
Advisor(s):
Eric Simanek
Chemistry & Biochemistry
Location: SecondFloor, Table 8, Position 3, 11:30-1:30
View PresentationIn the pursuit of new ways to develop libraries of compounds for pharmaceutical drug discovery, the utilization of a robust and tunable macrocycle synthetic scaffold has led to the discovery of persistent and structurally well-defined conformational isomers. Targeting these macrocycles that exist as an ensemble of preorganized conformations represents a compromise between the pursuit of flexible molecules of undefined structure and rigid molecules biased towards a single conformation. This system is based on the quantitative dimerization of a monomer to afford macrocycle. When a single monomer is used, six unique structures are obtained. When two monomers are used, twenty unique structures are obtained. These different structures (conformational isomers) are accessed via hindered bond rotation with a barrier of ~18 kcal/mol and are observable by ¬1H NMR. Current drug discovery methods heavily rely on screening large chemical libraries of small, ridged molecules against protein targets and typically sacrifice entropy in favor of stronger ligand-target binding. Using our system, synthesis of 50 monomers allows for the generation of a library of over 10,000 structurally unique macrocycles. The goal of this work is to provide new chemical libraries for drug discovery.
CHEM2025DELBOSQUE12020 CHEM
Type: Graduate
Author(s):
Nora Del Bosque
Chemistry & Biochemistry
Advisor(s):
Kayla Green
Chemistry & Biochemistry
Location: Basement, Table 5, Position 1, 1:45-3:45
View PresentationEUK-134 is a manganese-salen complex widely used in anti-aging skincare formulations due to its potent antioxidant activity resulting from catalytic decomposition of reactive oxygen species. Despite its popularity, the fundamental kinetic properties that govern its efficacy and recyclability are not well understood, limiting its optimization in skincare products. As a result, the study presented here investigates the efficiency, sustained activity, and selectivity of EUK-134 in comparison to the Green lab ligand library by evaluating its turnover number (TON), turnover frequency (TOF), and reaction rate. Results indicate that while EUK-134 demonstrates high catalase-type activity and selectivity, the activity decreases with continuous exposure to H₂O₂, suggesting a need for re-application in real-world scenarios to achieve long-term protection. Additionally, selectivity studies show that peroxidase activity was observed, which may impact the stability of sensitive ingredients in formulations. These findings provide essential kinetic benchmarks to compare future small molecules and optimize EUK-134’s use in antioxidant skincare products. Without a clear understanding of these fundamental properties, we lack benchmarks to compare future small molecules that compete with EUK-134.
CHEM2025DINH46098 CHEM
Type: Undergraduate
Author(s):
Ngan Dinh
Chemistry & Biochemistry
Advisor(s):
Onofrio Annunziata
Chemistry & Biochemistry
Location: SecondFloor, Table 3, Position 3, 1:45-3:45
View PresentationPerfluoroalkyl substances (PFAS), known as "forever chemicals", are ubiquitous environmental contaminants whose remarkable persistence poses significant risks to human health and ecosystems. Thus, it is important to develop analytical assays to determine PFAS concentrations based on widely accessible, readily available instrumentation, such as UV-VIS spectrophotometry. Tetrasodium tetraphenylporphyrintetrasulfonate (TPPS) is a water-soluble porphyrin known for its spectrophotometric property in water. It is also known that TPPS binds to the protein bovine serum albumin (BSA). We investigated the effect of BSA on the absorption spectrum of TPPS and how PFAS presence impacts BSA-TPPS interaction in water. Interestingly, we found that BSA induces TPPS precipitation. As BSA concentration increases, TPPS solubility first dramatically decreases, then increases, ultimately leading to the formation of homogeneous solutions at relatively high BSA concentration. Furthermore, addition of two different PFAS, sodium perfluorohexanoate and potassium perfluorobutanesulfonate salts, to homogeneous BSA-TPPS mixtures appreciably alter TPPS spectra. Our results show that these mixtures can be used to produce calibration curves relevant to the determination of PFAS concentrations in water.
CHEM2025DOWNUM4253 CHEM
Type: Undergraduate
Author(s):
Annie Downum
Chemistry & Biochemistry
Liam Claton
Chemistry & Biochemistry
Advisor(s):
Eric Simanek
Chemistry & Biochemistry
Location: Basement, Table 7, Position 1, 1:45-3:45
View PresentationSome of the most effective drugs from Nature are large and ring-shaped, so-called macrocycles. Macrocycles are interesting because they can interfere with protein-protein interactions, a different strategy for therapy than that used by small molecules (like aspirin). The challenge with the design of macrocycle drugs is that they are difficult to make and behave unpredictably. Here, an efficient strategy to make macrocycles is described. These molecules behave consistently (with preserved shapes) and can be tailored to optimize binding (a hallmark of drug design). The two macrocycles described differ in the choice of one group with significant (and predictable) consequences. Both groups mimic amino acid sidechains that are implicated in protein-protein interactions. One amine, N-methylbenzylamine, yields a macrocycle that will adopt six conformations in solution (an advantage when looking for drugs). The second amine, isobutylamine, gives more than eight conformations. Structural analysis was accomplished by NMR spectroscopy.
CHEM2025DUNN45262 CHEM
Type: Graduate
Author(s):
Sarah Dunn
Chemistry & Biochemistry
Benito Morales
Chemistry & Biochemistry
Natalie Plascencia
Chemistry & Biochemistry
Advisor(s):
Kayla Green
Chemistry & Biochemistry
Location: SecondFloor, Table 5, Position 1, 1:45-3:45
View PresentationThe development of novel anticancer agents with enhanced selectivity and reduced toxicity remains a critical challenge in medicinal chemistry. In this study, we investigate the influence of the quinoline moiety on the pharmacological properties of tetra-aza pyridinophanes, with a focus on their anticancer activity. A series of structurally diverse derivatives were synthesized, incorporating variations in the quinoline moiety position and R-group functionalization. The compounds were characterized using multiple spectroscopic and analytical techniques, and their biological activity was evaluated in cancer cell lines. Results indicate that the presence of the quinoline moiety significantly improves anticancer efficacy compared to its absence, suggesting enhanced interactions with cellular targets. Furthermore, permeability studies reveal that the methoxy (-OMe) substitution on the pyridine ring enhances cellular uptake relative to the hydroxyl (-OH) counterpart. These findings highlight the potential of quinoline-functionalized tetra-aza pyridinophanes as promising candidates for targeted cancer therapy. By improving the selectivity between normal and cancerous cells, this work advances the design of next-generation chemotherapeutics with reduced systemic toxicity.
CHEM2025FITTERER39705 CHEM
Type: Undergraduate
Author(s):
Ella Fitterer
Chemistry & Biochemistry
Advisor(s):
Jean-Luc Montchamp
Chemistry & Biochemistry
Location: SecondFloor, Table 2, Position 3, 1:45-3:45
View PresentationThis project is to synthesize a known nanomolar inhibitor of dehydroquinate synthase for evaluation as an antimicrobial agent in collaboration with TCU's Biology Professor McGillivray. It is estimated that nearly 10 million individuals could die per year due to antimicrobial resistance by the year 2050 (1). The focus will be two-fold: first, the improved synthesis of alkenylphosphonate 1, and then its elaboration into various prodrugs to improve its activity in vivo. The in vitro activity of 1 on dehydroquinate synthase is Ki = 0.29 nM, while the enzyme's substrate has Km = 4 microM (2). Dehydroquinate synthase is an enzyme that is part of the aromatic amino acid biosynthetic pathway, which is essential to bacteria and plants but does not exist in mammals - which is why we must eat vegetables and fruits. Thus, the toxicity to humans of antibacterial compounds targeting this pathway should be minimized.
Compound 1 was synthesized previously (2), but improvements to its synthesis must be made since it will be the starting material for the preparation of prodrugs. Prodrugs are compounds that are precursors of 1 but where the charge is masked. Because inhibitor 1 is highly hydrophilic, this prodrug strategy should be necessary to achieve biological activity in vivo. Initial work will aim at the large-scale preparation of 1 and particularly eliminate as much as possible the need for purification by chromatography.
CHEM2025GRUBBS56097 CHEM
Type: Graduate
Author(s):
Maegyn Grubbs
Chemistry & Biochemistry
Sergei Dzyuba
Chemistry & Biochemistry
Zygmunt Gryczynski
Physics & Astronomy
Bong Lee
Physics & Astronomy
Advisor(s):
Jeff Coffer
Chemistry & Biochemistry
Location: Basement, Table 4, Position 2, 11:30-1:30
View PresentationMetal-halide perovskites are crystalline semiconductive materials with a tunable direct bandgap, defect tolerance, and high charge carrier mobility. These useful properties have led to application perovskites such as LEDs, solar cells, and more recently lasers.
In this project, cetyl ionic liquid (IL) enhanced Methylammonium Lead Tribromide perovskites thin films were studied on substrates with varying refractive indices to determine how refractive index impacts photophysical properties. Methylammonium Lead Tribromide perovskites have a refractive index of 2.19. In comparison glass, a common substrate, has a refractive index of 1.51 while yttrium-stabilized zirconium oxide (YSZ) is 2.15.
Thin films of Methylammonium Lead Tribromide grown on yttrium-stabilized zirconium oxide (YSZ) in the presence of an ionic liquid are found to be strongly emissive in the green at a wavelength of 535 nm (with quantum efficiency values above 60%). The associated photoluminescence excitation (PLE) spectra show an unprecedented series of distinct peaks, one set with an average energy separation of ~200 milli-electron volts, the other set with a ~100 milli-electron volt separation indicating possible Giant Rashba Splitting. The preparation and structure of these films, along with origins of this splitting, are presented.
CHEM2025GUERNSEY10000 CHEM
Type: Graduate
Author(s):
Ellis Guernsey
Chemistry & Biochemistry
Advisor(s):
Location: Basement, Table 6, Position 3, 11:30-1:30
View PresentationAsymmetric chemical transformations are essential, given that most pharmaceuticals are chiral. However, the industrial implementation of an asymmetric catalyst relies on basic economic principles. For an economically viable synthesis, catalysts should be readily available, cost-effective, and environmentally sustainable. We are synthesizing and evaluating a series of chiral phosphorus acids (CPAs) as catalysts for asymmetric transformations. Building on our previous work, we are developing P-chiral phosphorus acids as Brønsted acid catalysts for the acid-catalyzed asymmetric transformations.
CHEM2025HARVEY11750 CHEM
Type: Undergraduate
Author(s):
Tatum Harvey
Chemistry & Biochemistry
Ibukun Alausa
Biology
Grace Bobo
Chemistry & Biochemistry
Nick Boehly
Biology
Delaney Davis
Biology
Audrey Dolt
Biology
Annie Downum
Chemistry & Biochemistry
Isabelle Galvan
Biology
Jacquelyn Ha
Biology
Daisy Li
Chemistry & Biochemistry
Aidan Meek
Biology
Jonah Morgan
Engineering
Kadie Nguyen
Chemistry & Biochemistry
Mark Sayegh
Chemistry & Biochemistry
Samantha Shah
Chemistry & Biochemistry
William Stites
Biology
Sophia Tunks
Chemistry & Biochemistry
Lexi Winter
Biology
Amarige Yusufji
Chemistry & Biochemistry
Troy Zambak
Biology
Advisor(s):
Kayla Green
Chemistry & Biochemistry
Heidi Conrad
Chemistry & Biochemistry
Julie Fry
Chemistry & Biochemistry
Location: SecondFloor, Table 4, Position 3, 1:45-3:45
View PresentationLab safety across independent academic and research labs for undergraduate and graduate students is critical to creating a successful chemistry experience. Many students at Texas Christian University (TCU) are heading into the medical field where healthcare professionals work in sensitive and controlled environments every day. Others are moving to research and industrial labs where safety is a critical component of success. Safety concerns constantly arise within these environments. Understanding how to manage a hazard or safety concern is a critical skill that translates to a successful professional skillset and creates a positive professional environment. TCU is offering a groundbreaking safety course for undergraduates and graduate students starting Fall 2024. Students in the course will focus on learning objectives from American Chemical Society’s, “Guidelines for Chemical Laboratory Safety in Academic Institutions”. The TCU Chemistry Club is working to complement this new course with a campus awareness campaign and include local elementary schools that work with Chemistry Club. We will be discussing the various awareness strategies that the Chemistry Club has implemented to achieve awareness at various campuses.
CHEM2025HARVEY37254 CHEM
Type: Undergraduate
Author(s):
Tatum Harvey
Chemistry & Biochemistry
Advisor(s):
Benjamin Janesko
Chemistry & Biochemistry
Location: FirstFloor, Table 3, Position 1, 11:30-1:30
View PresentationPredicting pKa and pH-dependent speciation is an important aspect of drug design. Often, pKa behaviors govern various properties including solubility, docking poses, and membrane permeability of drug molecules. Understanding these properties is critical for synthesizing an applicable drug molecule for a given ailment. Traditionally, fairly accurate computational pKa predictions are achievable for small rigid gas-phase molecules with a single acid/base site. However, the same level of accuracy has not been reached for larger, macrocyclic molecules that more closely resemble pharmaceuticals. To predict the pKa for their large, flexible, polybasic molecules in water, new workflows were developed to account for solvation and conformational dynamics incurred by these larger molecules in solution. We evaluated a series of flexible tetra-aza macrocyclic small molecules derived from pyclen using conformational analysis alongside continuum solvent models and DFT calculations to obtain pKa predictions. Utilizing a linear fit we can obtain an RMSD of 0.9 pKa units which is competitive with the best physics-based methods in the SAMPL6 benchmark for pKa predictions. This presentation will focus on the development of the workflow, benchmarking, and results.
CHEM2025HO14530 CHEM
Type: Undergraduate
Author(s):
Minh Ho
Chemistry & Biochemistry
David Freire
Chemistry & Biochemistry
Kayla Green
Chemistry & Biochemistry
Benjamin Janesko
Chemistry & Biochemistry
Advisor(s):
Benjamin Janesko
Chemistry & Biochemistry
Location: Third Floor, Table 2, Position 3, 11:30-1:30
View PresentationSuperoxide dismutase (SOD) enzymes are a major defense against superoxide, which is a potent reactive oxygen species. SOD mimics have potential clinical relevance as treatments for neurodegenerative diseases. The Green group at TCU synthesized tetra-aza macrocycle copper complexes since they serve as promising SOD mimics. The redox potential of these complexes is a critical factor in their antioxidant activity, as it determines their ability to bind and transfer electrons. However, the vast number of possible tetra-aza macrocycles presents a challenge for experimental synthesis and testing. To address this, we perform computational simulations to predict the redox potential of un-synthesized tetra-aza macrocycles, helping to identify the most promising candidates for further study. This work, in combination with other predictive models for properties such as pKa, solubility, permeability, and metal binding, accurate redox potential simulations can help focus experimental efforts on the most viable SOD mimics, accelerating the development of effective treatments.
CHEM2025IGWILO30047 CHEM
Type: Undergraduate
Author(s):
Favor Igwilo
Chemistry & Biochemistry
Qamar Hayat Khan
Chemistry & Biochemistry
Daisy Li
Chemistry & Biochemistry
Ines Soto
Chemistry & Biochemistry
Advisor(s):
Benjamin Sherman
Chemistry & Biochemistry
Location: Third Floor, Table 10, Position 1, 1:45-3:45
View PresentationLiquid Phase Deposition of Nickel Oxide as a Hole Transport Layer for TEMPO-Mediated Oxidation
Favor Igwilo, Texas Christian University, Class of 2026
Laboratory of Dr. Benjamin Sherman, PhD;
Department of Chemistry and BiochemistryEfficient positive charge (hole) transport is essential in photoelectrochemical systems for driving oxidation reactions. In our target process, 2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPO), a stable free radical mediator, drives the redox reaction of benzyl alcohol to benzaldehyde, a reaction with significant applications in industrial processes and synthetic chemistry. TEMPO-mediated oxidation offers a sustainable alternative to conventional oxidation methods that generate hazardous waste, highlighting the need to enhance its viability in photoelectrochemical applications. Nickel oxide (NiO), a p-type semiconductor, is suited for this role due to its hole transport ability, abundance and cost-effectiveness compared to conventional alternatives such as TiO₂. To integrate NiO as a hole transport layer in TEMPO-mediated oxidation, we developed a liquid phase deposition (LPD) protocol for fabricating uniform NiO films on fluorine-doped tin oxide (FTO) glass. These films were incorporated into FTO|WO3-BiVO4 photoanodes to improve charge separation and hole extraction under light conditions.
Our experiments indicates that the uniformity and quality of NiO films are affected by deposition parameters, including the pH of the boric acid (H₃BO₃) solution, the type of base employed for pH adjustment (NH₄OH vs. NaOH)), and the temperature of nickel(II) fluoride tetrahydrate (NiF₂·4H₂O) to H₃BO₃ precursors. Characterization by profilometry reveals that maintaining a pH between 7.5 and 8 consistently produces uniform films with thicknesses in the range of 100–200 nm. UV–Vis spectroscopic analysis confirms the expected optical absorption of NiO in the near-ultraviolet region, while further electrochemical characterizations via cyclic voltammetry and chronoamperometry will further assess hole transport efficiency. This work establishes a scalable approach for NiO film fabrication that will enhance the performance of WO₃–BiVO₄ photoanodes in TEMPO-mediated oxidation processes, advancing sustainable, solar-driven alcohol oxidation with reduced environmental impact.
CHEM2025KULLA13568 CHEM
Type: Undergraduate
Author(s):
Emma Kulla
Chemistry & Biochemistry
Emily Rathke
Chemistry & Biochemistry
Advisor(s):
Jean-Luc Montchamp
Chemistry & Biochemistry
Location: SecondFloor, Table 1, Position 2, 1:45-3:45
View PresentationEmma Kulla, ¹Emily Rathke, ¹Braden Chadwick, Shauna M McGillivray, and Jean-Luc Montchamp*
¹Contributed equally
"Synthesis of Penicillin G Prodrugs and Assessment of Antibiotic Activity"
ABSTRACT
The goal of our project is to synthesize and evaluate prodrugs for phosphorus-containing antibiotics. To begin, we evaluated common prodrug moieties. This is because the preparation of phosphorus prodrugs is significantly more complex than that of carboxylic acids. In an attempt at determining the best prodrug moieties or at least establish if there are significant differences among the various bacterial strains, a series of compounds was synthesized. Penicillin G (potassium salt) was chosen as the model compound since it is a well-established antibiotic, and since there is only a carboxylate group needing derivatization. The potassium salt of penicillin G (PenCOOK) was esterified directly to PenCOOR by alkylation in DMF. The following R groups have been prepared: CH₂OC(O)t-Bu, CH₂C₆H₄(4-OAc), CH₂C₆H₄(4-NO₂), and CH₂C₆H₅. The former two compounds should be triggered by bacterial esterases, whereas the nitrobenzyl ester should be triggered by bacterial nitrogenases. The benzyl ester provides a control for the para-substituted benzyl derivatives. These compounds were then tested against the gram-positive pathogen, Bacillus anthracis Sterne. We find that the minimum inhibitor concentration (MIC) of the control (non-derivatized) penicillin-G was 120 μM (approximately 40 μg/ml), which is consistent with our previous studies. The addition of the prodrug moieties substantially increased the effectiveness of penicillin for all 4 pro-drugs. This result was most striking with EK31 (R = CH₂OC(O)t-Bu), which lowered the MIC to 3.75 μM (1.25 μg/ml). These results may be confounded by the lack of solubility of these prodrugs in aqueous media as EK31 also had the best solubility of the prodrugs tested. Future experiments will be needed to address this challenge and optimize the prodrugs, but our results indicate this is an effective approach.
CHEM2025LANYON51865 CHEM
Type: Undergraduate
Author(s):
Spencer Lanyon
Chemistry & Biochemistry
Sarah Dunn
Chemistry & Biochemistry
Hannah Pyle
Chemistry & Biochemistry
Advisor(s):
Kayla Green
Chemistry & Biochemistry
Location: Third Floor, Table 1, Position 1, 1:45-3:45
View PresentationOxidative stress through the production of reactive oxygen species (ROS) has been shown to damage molecules in the brain and lead to the neuronal damage characteristic of AD. Additionally, metal ions like iron, copper, and zinc have been shown to not only bind to amyloid beta proteins and induce their aggregation, one hallmark of AD, but these metals also stimulate the production of ROS. To effectively fight AD, therapeutics should not only be able to chelate these metals and reduce oxidative stress but also prevent the aggregation of amyloid beta proteins. The Green Lab has produced ligands that both effectively chelate metals and reduce oxidative stress through interacting with ROS, but these ligands simply prevent the progression of the disease without affecting amyloid-beta protein aggregation directly. In this presentation, a synthetic scheme is proposed for the creation of a Green Lab ligand with the KLVFF peptide attached. The KLVFF peptide in the past has been shown to prevent amyloid-beta plaques from aggregating in vitro. Additionally, research has also been done showing that KLVFF, when attached to nanoparticles, can pass through RAGE receptors that are produced in the brains of AD patients. Through the addition of this peptide to the ligand, a small molecule that can chelate transition metals, reduce the effects of ROS, and prevent amyloid-beta aggregation will have been synthesized, providing a potential new therapeutic solution for Alzheimer's Disease treatment.
CHEM2025LE44584 CHEM
Type: Undergraduate
Author(s):
Minh Le
Chemistry & Biochemistry
Onofrio Annunziata
Chemistry & Biochemistry
Josie Nguyen
Chemistry & Biochemistry
Nick Reuter
Chemistry & Biochemistry
Advisor(s):
Onofrio Annunziata
Chemistry & Biochemistry
Location: Third Floor, Table 5, Position 1, 1:45-3:45
View PresentationSalt-induced diffusiophoresis is the migration of a charged nanoparticle in water, induced by an imposed directional gradient of salt concentration. This transport phenomenon has emerged as a valuable tool for particle manipulation inside porous materials and microfluidics. Micelles represent a common example of nanoparticles with the crucial ability of hosting small guest molecules. Thus, micelle diffusiophoresis is important in the manipulation of small molecules. Micelle diffusiophoresis depends on micelle Brownian mobility or diffusion coefficient. This transport parameter describes the intrinsic ability of a micelle to randomly move (diffuse) in water. The poster reports diffusion-coefficient measurements carried out on aqueous solutions of the surfactant, hexadecylpyridinium chloride (CPC), in the presence of aqueous NaCl by dynamic light scattering. The effect of surfactant and salt concentrations on the diffusion coefficient of CPC micelles is discussed. These data are used to characterize salt-induced diffusiophoresis of charged micelles.
CHEM2025LI27437 CHEM
Type: Undergraduate
Author(s):
Daisy Li
Chemistry & Biochemistry
Qamar Hayat-Khan
Chemistry & Biochemistry
Favor Igwilo
Chemistry & Biochemistry
Advisor(s):
Benjamin Sherman
Chemistry & Biochemistry
Location: SecondFloor, Table 8, Position 1, 1:45-3:45
View PresentationTungsten oxide (WO₃) is a promising semiconductor material for photoelectrochemical applications due to its stability and visible-light activity. This project focuses on the fabrication and electrochemical characterization of WO₃ thin films on fluorine-doped tin oxide (FTO) glass . WO₃ films were successfully prepared by the dip-coating method, followed by thermal treatment at 450°C.
The WO₃ films were then characterized using ultraviolet-visible spectroscopy, cyclic voltammetry, and chronoamperometry. The photoelectrochemical measurements were performed using a TEMPO(2,2,6,6-tetramethylpiperidine-1-oxyl)-mediated oxidation system under both illuminated and dark conditions, which can be used for future oxidative coupling reactions.
Future work will focus on integrating WO₃ films with bismuth vanadate (BiVO₄) and nickel oxide (NiO) to develop multilayer photoelectrodes and provide insight into the optimization of photoelectrochemical cells.
CHEM2025MORGAN44815 CHEM
Type: Undergraduate
Author(s):
Jonah Morgan
Chemistry & Biochemistry
Advisor(s):
Benjamin Janesko
Chemistry & Biochemistry
Location: Basement, Table 12, Position 2, 11:30-1:30
View PresentationDensity Functional Theory (DFT) is a method for simulating molecules by approximating their electron densities, with various functionals available to model these systems. M11plus is one such functional, a range-separated hybrid meta functional that combines long-range non-local Hartree–Fock exchange with the non-local Rung 3.5 correlation, which has demonstrated effectiveness across a broad range of chemical databases. This work implements the M11plus functional into the PySCF open-source Python library and reparametrizes necessary fitting constants.