Chemistry Commons^™

Ni2-Imido Bispincer Platforms: Cooperative Reactivity Enabled Through Substrate Addition Across A Ni2n Unit, David De Los Santos, Kritika Gour, Manar M. Shoshani

School of Integrative Biological & Chemical Sciences Faculty Publications

Transition metal imido complexes are renowned for their capacity to undertake challenging 1,2 additions owing to the high basicity of the imido moiety. Access to transition metal imidos is often limited to the addition of organic azides to metal precursors, hindering the design of molecular constructs incorporating imido units. Bimetallic bispincer complexes, 1 and 2, are presented, which are anchored by a central imido moiety supported by pyridyl imine donors, forming highly planarized Ni2N-aryl cores. Complex 2, which also features a Ni─Ni σ-bond, is able to engage in cooperative substrate cleavage of main group hydrides via a formal 1,2 addition …

Interfacial Redox Mediation By Amine/Alkyne-Functionalized Silicon Nanoparticles: Surfactant-Free Gold Nanoparticle Synthesis, Amber L. Garcia, Brittany Griggs, Brian S. Mitchell, Mark J. Fink, Julie P. Vanegas

Physics & Astronomy Faculty Publications

We develop a surfactant-free synthesis method for gold nanoparticles (AuNPs) using 2-propynylamine-functionalized silicon nanoparticles as integrated redox-active supports. Surface-anchored amine groups act as built-in reducing sites for Au³⁺ precursors at the hexane–water interface under ambient conditions, enabling in situ AuNP nucleation and growth. Time-resolved UV-vis spectroscopy and dynamic light scattering track the emergence of plasmonic AuNPs, while quantitative morphology analysis reveals a final population dominated by spherical and near-spherical nanoparticles (∼74%), with faceted polyhedral structures (∼4%) and dendritic, hollow, irregular, and rod-like morphologies (∼22%) as minority species. The temporal evolution proceeds from early dendritic and irregular aggregates to a …

Insights Into Androgen Receptor Allosteric Modulation By P,P'-Dichlorodiphenyldichloroethylene Binding At The Binding Function-3 Site And Site-Specific Binding Function-3 Mutations, Emanuel Aggeo Flores

Theses and Dissertations

One of DDT’s metabolites, p,p’-dichlorodiphenyldichloroethylene (DDE), has been classified as an endocrine disrupting chemical (EDC) due to its ability to interfere with hormone signaling by binding to nuclear receptors (NR) such as the androgen receptor (AR).

Structurally, the AR contains a ligand-binding domain (LBD) where endogenous steroids bind. Furthermore, the LBD contains a surface binding site known as binding function-3 (BF-3), which studies suggest exerts an allosteric effect on bound DHT when small, hydrophobic molecules bind.

Here, we present a study that examines how specific BF-3 site mutations and DDE binding affect steroid stability within the LBP utilizing computational methods. …

General Chemistry Students' Perceptions Of How Various Course Resources Affect Their Learning And Exam Preparation, Jennifer Scoggin Cortez

Theses and Dissertations

The tertiary-level first-semester general chemistry course has a large range of material with different complexities that can be difficult for students to master within one semester. In the general chemistry I course under study here, students were provided with a variety of resources to help with their learning and understanding, with various components of the course, including the lecture, online textbook, Peer-Led-Team-Learning (PLTL) study sessions, and exams, having associated resources. This study aims to analyze students’ experiences with these various resources. Students were given semi-structured interviews where they talked about their experiences with the resources and provided insight into more …

Probing The Dynamic Behavior Of The Androgen Receptor In The Presence Of Heptyl And Methyl Parabens, Edgardo De Leon

Theses and Dissertations

The androgen receptor (AR) mediates physiological signaling from endogenous androgens, a function that can be disrupted by endocrine disruptors with serious reproductive and developmental consequences. Parabens, widely used preservatives, inhibit AR signaling in cell-based assays, with inhibitory potency correlating with alkyl chain length: heptylparaben exhibits stronger antagonism than methylparaben, which shows no effect. We hypothesize this differential potency arises from allosteric modulation at the AR Binding Function 3 (BF-3) site, altering dihydrotestosterone (DHT) binding dynamics. Docking calculations using antagonist-bound AR crystal structures, followed by molecular dynamics simulations, show that methylparaben fails to remain bound at BF-3, whereas heptylparaben maintains stable …

Structure–Property Engineering Of Sn-Based Hybrid Perovskites Via Bulky Organic Cation Incorporation: From 3d To 2d Architectures, Kevin Alejandro

Theses and Dissertations

This thesis investigates tin-based hybrid organic/inorganic perovskites (HOIPs) as a lead-free alternative to silicon solar cells. To manipulate optoelectronic and efficiency of the semiconductors, methylammonium was substituted with bulky propylammonium and tetrabutylammonium cations to induce quasi-2D/3D Ruddlesden-Popper phases. X-Ray Diffraction confirmed 2D layered phases in propylammonium hybrids (5-15%), while tetrabutylammonium hybrids faced steric limits, triggering vacancy ordered perovskite phases at 1% concentration. Optical analysis showed a bandgap narrowing from 1.30 eV to 1.26 eV with increased substitution. Although photovoltaic performance generally declined, the 10% propylammonium hybrid achieved the highest fill factor of ~0.79, indicating superior internal charge transport. This work …

Electrocatalytic Degradation Of Methylene Blue Using Rgo, Sb2o3, And Rgo-Sb2o3 Composite Ink-Based Electrodes, Maria Irene Myers Armas, Andrea M. Fletes, Thomas Eubanks, Arnulfo Mar, Jason Parsons, Helia Magali Morales

School of Integrative Biological & Chemical Sciences Faculty Publications

Water pollution from industrial dyes is a critical challenge due to the resistance of these types of compounds to degradation and potentially harmful effects on living organisms and human health. In this study, the electrochemical degradation of methylene blue (MB) was investigated using ink-based copper foam electrodes with reduced graphene oxide (rGO), antimony trioxide (Sb2O3), and rGO/Sb2O3 composites. The materials used to synthesize the electrodes were characterized by X-ray diffraction (XRD), which showed the successful synthesis of GO, rGO, and the Sb2O3-rGO composite. Additionally, the synthesized electrodes were examined using SEM. The MB degradation was studied using kinetic behavior and …

Synthesis Of Antibody Functionalized Polyaniline/Polystyrene/N-Gqds Composite Fibermats For Sweat Based Cortisol Biosensing Applications, Ashwin James

Honors Theses

Noninvasive, wearable biosensors capable of detecting stress biomarkers in sweat require electrodes that are flexible, conductive, insoluble in water, and highly sensitive at low concentrations of analyte. In this work, bovine serum albumin blocked and anti-cmab immobilized nitrogen doped graphene quantum dots integrated polyaniline/polystyrene composite fibermat electrodes (BSA/Anti-Cmab/N-GQDs/PANI/PS electrodes) were synthesized and evaluated as a potential platform for an electrochemical cortisol biosensor in sweat based systems. Polyaniline was utilized in order to provide electrical conductivity, while polystyrene served as a carrying polymer for mechanical support and its hydrophobicity. Composite fibermats were manufactured through Forcespinning™, followed by a secondary polyaniline graft …

Cosmetic Surgery And Physiological Disorder: You Should Talk To Someone About Your Unwinding Anxiety, Mona Muzammil, Washain Muzammil

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

Body dysmorphic disorder is a mental health condition in which you can't stop thinking about one or more perceived defects or flaws in your appearance — a flaw that appears minor or can't be seen by others. But you may feel so embarrassed, ashamed and anxious that you may avoid many social situations.

When you have body dysmorphic disorder, you intensely focus on your appearance and body image, repeatedly checking the mirror, grooming or seeking reassurance, sometimes for many hours each day. Your perceived flaw and the repetitive behaviors cause you significant distress and impact your ability to function in …

Rising Costs Of Higher Education In United States And Student Debt, Mona Muzammil, Muzammil Arshad, Washain Muzammil

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

100 years ago, college tuition at prestigious Ivy League colleges such as Harvard and Brown was about $130 per year. Even when adjusted for inflation, today's cost of higher education has increased dramatically to the point where a college education is shifting further out of reach for many Americans. This book explains the essential concepts in the debate regarding the staggering costs of higher education, supplying ten original essays by higher education policy experts, a lively historical narrative that provides context to current issues, and systematic guides to find additional sources of information on the subject.

Written from a historian's …

Behavioral Neuroscience Of Drug Addiction And Mental Disorder, Mona Muzammil, Muzammil Arshad, Washain Muzammil

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

This book explores the molecular, cellular, and neurocircuitry systems in the brain that are responsible for drug addiction. Common neurobiological elements are emphasized that provide novel insights into how the brain mediates the acute rewarding effects of drugs of abuse and how it changes during the transition from initial drug use to compulsive drug use and addiction. The book provides a detailed overview of the pathophysiology of the disease. The information provided will be useful for neuroscientists in the field of addiction, drug abuse treatment providers, and undergraduate and postgraduate students who are interested in learning the diverse effects of …

Electrocatalytic Degradation Of Methylene Blue Using Graphene Oxide, Antimony Oxide, And Graphene Oxide-Supported Antimony Oxide Ink-Based Electrodes, Maria Irene Myers Armas

Theses and Dissertations

This study investigates the electrocatalytic degradation of methylene blue (MB) using copper mesh electrodes coated with graphene oxide (GO), antimony oxide (Sb₂O₃), and their composite (GO/Sb₂O₃). These materials were evaluated across a pH range of 2 to 8 using sodium sulfate as the supporting electrolyte. UV-Vis spectroscopy at 665 nm confirmed dye degradation, with removal efficiencies reaching up to 95% at pH 2. However, degradation decreased at higher pH, with 40 – 60% removal at pH 8, depending on the electrode. Kinetic analyses revealed optimum performance under acidic conditions. GO/Sb₂O₃ electrodes demonstrated the most consistent and effective performance across all …

Physical And Chemical Characterization Of Recycled Glass Sand For Environmental Restoration, Shehbaz Ahmad, Julie P. Vanegas, Nicholas Borne, Natalia Butler, Toby Mendels, Leah A. Michaeloff, Diego Molina, Mary Salvaggio, Samantha Tamayo, Franziska Trautmann

Physics & Astronomy Faculty Publications

Introduction

We rely on coastal resources for food, water, and energy. However, over 75% of U.S. coastlines are eroding. Concurrently, the U.S. recycles less glass than other developed countries, landfilling hundreds of millions of tons every year. Recycled glass sand has many potential benefits over natural sand for combatting land loss; for example, it can be produced with controlled particle size to better resist erosion, making it an excellent—and underutilized—material for environmental restoration.

Objectives

This research compares the physical and chemical properties of recycled glass sand to natural sands (beach and dredge) from the U.S. Gulf Coast to assess environmental …

Integrated Density Functional Theory And Experimental Study Of Optical And Electronic Properties For Mos2/ (Metal=Au, Pt, Ni, Cu) And Mos2/Graphene/Metal Heterointerfaces, Shishir Timilsena, Sanju Gupta, Muhammad I. Bhatti, Nicholas Dimakis

School of Integrative Biological & Chemical Sciences Faculty Publications

We present computational simulations and experimental analyses of various heterointerfaces constructed from two-dimensional molybdenum disulfide (MoS2) and graphene on gold (Au), platinum (Pt), nickel (Ni), and copper (Cu) substrates. We combined density functional theory electronic structure, optical properties, and work function to elucidate heterostructure changes due to metal selection, corroborated with experimentally determined surface electronic properties. Here, we correlate shifts in the metal d-band center relative to the Fermi energy with the MoS2 bandgaps and bandgaps in the Dirac point region of the MoS2/graphene/Metal heterointerfaces. For the Ni heterointerfaces, the upshift of the metal d-band relative to the Fermi energy …

Architecture Of Pseudomonas Aeruginosa Glutamyl-Trna Synthetase Defines A Subfamily Of Dimeric Class Ib Aminoacyl-Trna Synthetases, Michael K. Fenwick, Stephen J. Mayclin, Steve Seibold, Amy E. Derocher, Sandhya Subramanian, Isabelle Q. Phan, David M. Dranow, Donald D. Lorimer, Ariel B. Abramov, James M. Bullard

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

The aminoacyl-tRNA synthetases (AaRSs) are an ancient family of structurally diverse enzymes that are divided into two major classes. The functionalities of most AaRSs are inextricably linked to their oligomeric states. While GluRSs were previously classified as monomers, the current investigation reveals that the form expressed in Pseudomonas aeruginosa is a rotationally pseudosymmetrical homodimer featuring intersubunit tRNA binding sites. Both subunits display a highly bent, “pipe strap” conformation, with the anticodon binding domain directed toward the active site. The tRNA binding sites are similar in shape to those of the monomeric GluRSs, but are formed through an approximately 180-degree rotation …

Nifuroxazide And 4-Hydroxybenzhydrazone Derivatives As New Antiparasitic (Trypanosoma Cruzi And Leishmania Mexicana) And Anti-Mycobacterium Tuberculosis Agents, Timoteo Delgado-Maldonado, Diana V. Navarrete-Carriola, Lenci K. Vazquez-Jimenez, Alma D. Paz-Gonzalez, Baojie Wan, Scott Franzblau, Othman Mueen Mohammed, Lorena Rodríguez-Páez, Charmina Aguirre-Alvarado, Debasish Bandyopadhyay

School of Integrative Biological & Chemical Sciences Faculty Publications

Background/Objectives: Nifuroxazide (Nfz) is a drug that has been used as a scaffold for designing antimicrobial and antiparasitic agents. This study aimed to synthesize and evaluate in vitro of Nfz and twenty-five 4-hydroxybenzhydrazone derivatives as potential anti-Trypanosoma cruzi, anti-Leishmania mexicana, and anti-Mycobacterium tuberculosis agents.

Methods: The compounds were synthesized by condensing 4-hydroxybenzhydrazide with appropriate aldehydes in acidic conditions and structurally confirmed by spectroscopic techniques. All compounds were evaluated in vitro against T. cruzi strains (NINOA and A1), L. mexicana (M379 and FCQEPS strains), and M. tuberculosis (H37Rv strain), followed by enzymatic assays against T. cruzi …

Vanadyl Phthalocyanine As A Low-Temperature/Low-Pressure Catalyst For The Conversion Of Fructose To Methyl Levulinate, Juan Luna, Mataz Alcoutlabi, Elizabeth M. Fletes, Helia Magali Morales, Jason Parsons

School of Integrative Biological & Chemical Sciences Faculty Publications

In this study, a vanadyl phthalocyanine was synthesized and characterized using XRD, FTIR, and XPS, confirming the successful metalation of the phthalocyanine ring. XRD analysis showed the vanadyl phthalocyanine crystallized in the P-1 crystal lattice, with unit cell parameters a = 12.058 Å, b = 12.598 Å, and c = 8.719 Å, and the lattice angels were 96.203°, 94.941°, and 68.204°. FTIR spectroscopy supported the metalation by the disappearance of the N-H stretch of the non-metalated phthalocyanine. The vanadyl phthalocyanine was tested as a heterogenous catalyst for the conversion of fructose into methyl levulinate in H2SO4–methanol and HCl–methanol systems. The …

Investigation Into The Effectiveness Of G-C3n4 For The Degradation Of Indigo Dye In Aqueous Solution Via Electrocatalysis, Rolando R. Barron Jr

Theses and Dissertations

Indigo dye (IUPAC 2-(3-hydroxy-1H-indol-2-yl)indol-3-one) is one of the most used dyes in the textile industry worldwide with more than 40,000 tons produced each year. It can elicit adverse physiological responses in humans including vomiting, diarrhea, and other gastrointestinal conditions, and it is toxic in large amounts. There is also evidence to suggest that indigo is a teratogen and genotoxic in aquatic life. Environmentally, the enormous amount of indigo used in the textile industry has caused rivers and waterways to run blue as well as severely impacting aquatic and plant ecosystems. The chemicals used in its synthesis are also …

Living With Alzheimer’S: A Guide To How To Lower The Risk Of Memory Loss & Care For Those With Alzheimer’S, Mona Muzammil, Washain Muzammil

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

Despite the frequent characterization of Alzheimer's disease as a “loss of self,"" this enlightening book demonstrates unequivocally that a person's unique self persists throughout the course of the disease. The important message in Caring for People with Alzheimer’s is how much can be done in care settings to support a person's sense of identity and thereby enrich the lives of people experiencing the many losses associated with dementia. Drawing from a diverse body of research, this book brings together the recommendations of the best thinkers and practitioners in multiple disciplines to illustrate the meaning of self and the importance of …

Effective Learning Strategies In Stem, Muzammil Arshad, Rebecca R. Romatoski, Mamoona Muzammil

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

Effective learning strategies were developed, implemented, and applied at five separate institutions of higher education in the United States, and one in the Middle East. The research has been dedicated to determining effective learning strategies for student learning and success. The research series developed grading rubric for homework and exams, developed a course structure for hybrid and face-to-face courses in STEM, and studied the impact of the syllabus design on student learning and motivation. A pedagogical methodology constituting the designed course structure was utilized to use various activity-based modules. Course lectures were designed to utilize PowerPoint presentations and/or OneNote as …

Dft Study Of The Mechanism Of Selective Hydrogenation Of Acetylene By Rhodium Single-Atom Catalyst Supported On Hy Zeolite, Melisa Su Yordanlı, Roberto Escobar, Jessica Meza, Deniz Akgül, Yuxin Zhao, Alper Uzun, Fatma Ahu Akin, Viktorya Aviyente, Abdurrahman Cagri Atesin, Tülay A. Ateşin

School of Earth, Environmental, & Marine Sciences Faculty Publications

The selectivity of acetylene hydrogenation by the Rh single-atom catalyst (SAC) supported on HY zeolite was investigated using density functional theory (DFT) and a 5/83T quantum mechanics/molecular mechanics (QM/MM) embedded cluster model. The calculated activation barrier (ΔG‡) for the oxidative addition of dihydrogen to the Rh metal center (15.9 kcal/mol) is lower in energy than that for the σ-bond metathesis of dihydrogen to the Rh—C bond (22.7 kcal/mol) and the Rh—O bond (28.4 kcal/mol). The activation barriers of the oxidative addition of subsequent dihydrogen molecules are significantly higher than that of the oxidative addition of the first dihydrogen molecule. These …

Density Functional Theory And Machine Learning Analysis Of C—C Reductive Coupling From Terminal Cyanido And Cyaphido Complexes, Roberto Magdiel Escobar

Theses and Dissertations

Carbon–carbon (C–C) bond activation has gained increased attention as a direct method for the synthesis of pharmaceuticals and industrial chemistry. Due to the thermodynamic stability and kinetic inaccessibility of the C–C bonds, however, activation of C–C bonds by homogeneous transition-metal catalysts under mild homogeneous conditions is still a challenge. Most of the systems in which the activation occurs either have aromatization or relief of ring strain as the primary driving force. The activation of unstrained C–C bonds of phosphaalkynes does not have this advantage. This study employs Density Functional Theory (DFT) calculations using the Gaussian16 package to elucidate and compare …

Evaluation Of Polymerization Condition Reactions Of Methyl Vinyl Ketone For Hydrogen Storage, Rituborna Ghosh

Theses and Dissertations

Hydrogen is widely regarded as one of the most promising clean alternative fuel sources; however, its widespread adoption has been hindered by significant challenges related to storage and transportation. Various storage methods have been proposed and developed, with continuous advancements being made to address these issues. Among the most effective solutions is the utilization of polymers, which serve as safe and efficient hydrogen storage media. This work investigated the polymerization of methyl vinyl ketone using different ratio of monomer: initiator and monomer: crosslinker using N,N′-methylenebisacrylamide (MBA) as crosslinker and ammonium persulfate (APS) as initiator in a free radical polymerization mechanism. …

Machine Learning Optimized Depolymerization Of Pet (Polyethylene Terephthalate) Via Glycolysis, Mehwash Aamir

Theses and Dissertations

Over 90% of the approximately 1 million PET bottles sold every minute end up in landfills or oceans, where they can persist for centuries. Plastic pollution urgently needs sustainable management and recycling solutions to mitigate the environmental impact of PET waste. From all techniques to recycle plastic waste, catalytic glycolysis stands out for its rapid reaction time, high monomer yields, lower costs, and enhanced durability.

In this work glycolysis of PET was evaluated under microwave conditions using 1,5,7-Triazabicyclo [4.4.0] dec5-ene (TBD) and 1,8-Diazabicyclo [5.4.0] undec-7-ene (DBU) as catalysts, being DBU as the best catalyst for further analysis. The effect of …

Microwave-Assisted Green Synthesis Of Spiroindolinopyranopyrazoles, Esther Owusu

Theses and Dissertations

Green Chemistry, usually known as sustainable chemistry, is widely implemented worldwide to safeguard human health and the environment. Recent investigations in organic synthesis and chemical transformation have demonstrated that green chemistry techniques are significantly reducing both chemical waste and reaction time. In order to fulfill this ecological requirement, it is crucial to lessen the utilization of perilous solvents and noxious chemicals, while also creating innovative reaction methods that decrease the production of trash. The implementation of such methodologies can greatly enhance the field of green chemistry. A more environmentally friendly synthetic method was utilized to generate spiro chemicals and their …

Teaching With Pedagogy And Empathy, Mamoona Muzammil, Muzammil Arshad, Washain Muzammil

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

Mental illness is common and can affect anyone. Each year the University welcomes students with Mental Health Issues. One in four adults in the US will experience a mental illness in their lifetime, however according to a NUS survey, eight out of ten students will experience a mental illness while in higher education. For some student’s mental illness can be a lifelong disability. Others can experience short term issues that emerge around difficult or stressful life events, while some students may be more at risk of experiencing mental illness in relation to their ethnicity, gender, sexuality or socio-economic background. Although …

Quinoxaline 1,4-Di-N-Oxide Derivatives As New Antinocardial Agents, Isidro Palos, Alonzo Gonzalez-Gonzalez, Alma D. Paz-Gonzalez, José C. Espinoza-Hicks, Debasish Bandyopadhyay, Norma Paniagua-Castro, Marlene S. Galeana-Salazar, Jorge Ismael Castañeda-Sánchez, Julieta Luna-Herrera, Gildardo Rivera-Sanchez

School of Integrative Biological & Chemical Sciences Faculty Publications

Mycetoma is currently considered as a neglected tropical disease. The incidence of mycetoma is unknown but most of the worldwide cases are present in the “mycetoma belt” including countries like Mexico, India, Senegal, and others. The treatment of mycetoma depends on the etiological agent responsible for the case. Treatment success reaches 60 to 90%; however, common treatment has been reported to be ineffective in some cases, due in part to resistance to the prescribed antibiotics. Therefore, it is necessary to develop new therapeutic options. In the past two decades, quinoxaline derivatives have shown relevance as antibacterial agents. Therefore, in this …

A Dft Comparison Of C–C Reductive Coupling From Terminal Cyanido And Cyaphido Complexes Of Nickel, Roberto Escobar, Jessica Meza, Javier Pena, Abdurrahman Atesin, William D. Jones, Christian Müller, Tülay A. Ateşin

School of Integrative Biological & Chemical Sciences Faculty Publications

The density functional theory study of the thermal C–C reductive coupling from terminal cyanido and hypothetical cyaphido complexes of [Ni(dmpe)] (dmpe = 1,2-bis(dimethylphosphino)ethane) revealed the key reaction intermediate in the reductive C–CP coupling being a σ-CC complex unlike an η2-aryl complex in the Ni C–CN system, as already observed in our previous studies. The reaction in THF is endothermic by 4.9 kcal/mol for cyanido with a 32.0 kcal/mol activation barrier and exothermic by 28.5 kcal/mol for cyaphido with an 11.3 kcal/mol activation barrier. To compare our results with the existing experimental data, we chose mesityl as the aryl group and …

Synthesis And Characterization Of Nial-Hydride Heterometallics: Perturbing Electron Density Within Al–H–Ni Subunits, Aleida G. Gonzalez, Fernando Gonzalez, Edgar De Leon, Kaitlyn M. Birkhoff, Sam Yruegas, Haoyuan Chen, Manar Shoshani

School of Integrative Biological & Chemical Sciences Faculty Publications

Heterometallic hydride complexes are of growing interest due to their potential to contribute to highly active insertion-based catalysis; however, methods to modulate electron density within this class of molecules are underexplored. Addition of ancillary ligands to heterotrimetallic NiAl2H2 species (1) results in the formation of heterobimetallic NiAl-hydride complexes with varying phosphine donors (2-(L)2). Incorporation of sigma donating ancillary ligands of increasing strength led to contractions of the Ni–Al distances correlated to a strengthening of a back donation interaction to the Al–H sigma antibonding orbital, most prominently present in 2-(PMe3)2. Demethylation of the aryl ether from 2-(PMe3)2 provides access to a …

Synthesis And Characterization Of Medicinally Privileged Aza Heterocycles, Nneoma James

Theses and Dissertations

Four-membered cyclic amides, commonly known as β-lactams, have played a crucial role in drug discovery research since its discovery by Alexander Fleming in 1928 from Penicillium notatum. The β-lactam antibiotics are broadly effective against several bacterial infections through acylating the transpeptidase involved in cross-linking peptides to form peptidoglycan or periplasmic murein, which is a fundamental constituent of the bacterial cell wall for both the gram-positive (ten or more layers) and gram-negative (one or two layers) bacteria. Although for more than eight decades, β-lactams have been recognized as antibiotics, later, other medicinal activities of β-lactam derivatives have been reported, including lowering …