Organic Chemistry Commons^™

Synthesis And Characterization Of A Novel Reaction-Based Azaborine Fluorescent Probe Capable Of Selectively Detect Carbon Monoxide Based On Palladium-Mediated Carbonylation Chemistry, Samuel Moore, Carl Jacky Saint-Louis

Symposium of Student Scholars

Azaborines are fascinating compounds because they possess valuable properties such as photochemical stability, have high molar absorption coefficient and high fluorescent quantum yields, as well as large Stokes shifts and tunable absorption/emission spectra. Here, we designed, synthesized, and will examine a novel reaction-based azaborine fluorescent probe capable of selectively detect carbon monoxide (CO) based on palladium-mediated carbonylation chemistry. This novel azaborine fluorescent probe will exhibit high selectivity for CO and display a robust turn-on fluorescent response in the presence of CO in aqueous buffer solution.

Ketal-Azaborine Versus Ketal-Azaborine With A Spacer: Structural Effects On The Photophysical Properties Of Tunable Heteroaromatic Polycyclic Chromophores, Albert Campbell, Janiyah Riley, Samuel Moore, Albert Campbell

Symposium of Student Scholars

Flat-structured heteroaromatic polycyclic compounds with extended conjugated π-systems such as azaborines are in high demand in the material and imaging technology markets because of their unique features such as simultaneous tunability of fluorescence color and intensity. We have designed, synthesized, and investigated a series of novel conjugated thermally stable ketal-azaborine chromophores that contain a phenyl ring as a spacer between electronic moieties and the ketal-azaborine core as easily tunable high-luminescent organic materials. We investigated the impact of the phenyl spacer on the ketal-azaborine unit. We examined the structural effects on their photophysical properties by incorporating electron –donating and –withdrawing substituents …

Azaborine Versus Azaborine With A Spacer: Structural Effects On The Photophysical Properties Of Tunable Azaborine Chromophores, Kaia Ellis, Janiyah Riley, Lyric Gordon, Janiyah Riley

Symposium of Student Scholars

Azaborines are fascinating compounds because of their valuable and interesting optical properties making them suitable to be utilized in many optoelectronic devices. We have designed, synthesized, and investigated a series of novel conjugated thermally stable azaborine chromophores by incorporating a phenyl ring as a spacer linking the chromophore to different electronic moieties as easily tunable high-luminescent organic materials. We investigated the effect of the phenyl spacer on the azaborine unit. The substituent effects of different electronic moieties were investigated by the insertion of electron –withdrawing and –donating moieties to the phenyl spacer. We examined the role of the electron –donating …

Lipophilic Probes For Cellular Ethylene Detection, Morgan R. Brown

Electronic Theses and Dissertations

The structure of ethylene is simple, yet its biological effects are significant. When considering its role in biology it is almost exclusively regarded as a plant hormone. Research on ethylene from plants was progressed by several advancements in analytical instrumentation, from its discovery to elucidation of its signaling pathway. There is currently limited understanding of ethylene’s role in mammals, but evidence suggests that it may be a biomarker for oxidative stress! Additional tools and technology are crucial to study this surprising and important signaling role in mammals. Our group has developed molecular ethylene probes as a strategy to detect ethylene …

Biomimetic Synthesis Of Palladium Nanoparticles For Catalytic Application, Emily A. Groover

College of Graduate Studies: Theses & Dissertations

The synthesis of palladium nanoparticles (Pd NPs) using materials-directed peptides is a novel, nontoxic approach which exerts a high level of control over the particle size and shape. This biomimetic technique is environmentally benign, featuring nonhazardous ligands and ambient conditions. Nanoparticles are extremely reactive catalysts, boasting a large surface-to-volume ratio when compared to their bulk counterparts. The rational design of these nanoparticles using peptides has been very successful in aqueous environments, but no research has been done to apply it in organic systems. As such, the biomimetic synthesis of Pd NPs in an organic system is here investigated, with ethanol …

Microbial Labilization And Diversification Of Pyrogenic Dissolved Organic Matter, Aleksandar I. Goranov, Andrew S. Wozniak, Kyle W. Bostick, Andrew R. Zimmerman, Siddhartha Mitra, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

With the increased occurrence of wildfires around the world, interest in the chemistry of pyrogenic organic matter (pyOM) and its fate in the environment has increased. Upon leaching from soils by rain events, significant amounts of dissolved pyOM (pyDOM) enter the aquatic environment and interact with microbial communities that are essential for cycling organic matter within the different biogeochemical cycles. To evaluate the biodegradability of pyDOM, aqueous extracts of laboratory-produced biochars were incubated with soil microbes, and the molecular changes to the composition of pyDOM were probed using ultrahigh-resolution mass spectrometry (Fourier transform–ion cyclotron resonance–mass spectrometry). Given that solar irradiation …

Synthesis Of 6,6- And 7,7-Difluoro-1-Acetamidopyrrolizidines And Their Oxidation Catalyzed By The Nonheme Fe Oxygenase Lolo, Nabin Panth

Theses and Dissertations--Chemistry

One of the remarkable steps in loline alkaloid biosynthesis is the installation of an ether bridge between two unactivated C atoms in 1-exo-acetamidopyrrolizidine (AcAP). LolO, a 2-oxoglutarate-dependent nonheme Fe oxygenase, catalyzes both the hydroxylation of AcAP and the resulting alcohol's cycloetherification to give N-acetylnornoline (NANL). The mechanism of hydroxylation is well understood, but the mechanism of the oxacyclization is not. I synthesized difluorinated analogs of AcAP in an attempt to further understand the mechanism of the unusual cycloetherification step.

I prepared 6,6-F₂-AcAP in eight steps from N,O-protected 4-oxoproline. The key step was a Dieckmann …

Engineering Fluorescently Labeled Human Fibroblast Growth Factor One Mutants And Characterizing Their Photophysics Properties Towards Designing Fret Assays, Mamello Mohale

Graduate Theses and Dissertations

Human fibroblast growth factor one (hFGF1) belongs to a family of 22 FGF members produced by fibroblast cells. Cell signaling during physiological processes of angiogenesis and wound healing occurs when hFGF1 binds to its receptor (FGFR). However, when heterogenous homeostasis is not maintained, fibroblast cells exhibit excessive proliferation which can lead to a myriad of cancers. smFRET is an ultrasensitive distant dependent (1-10 nm) technique capable of resolving such heterogeneity in structural dynamics and binding affinities (Kd). Therefore, we successfully designed and characterized fluorescently labeled hFGF1 tracers which span the visible light region of the electromagnetic spectrum for use in …

Oxidation Alters The Architecture Of The Phenylalanyl-Trna Synthetase Editing Domain To Confer Hyperaccuracy, Pooja Srinivas, Rebecca E. Steiner, Ian J. Pavelich, Ricardo Guerrera-Ferreira, Puneet Juneja, Michael Ibba, Christine M. Dunham

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

High fidelity during protein synthesis is accomplished by aminoacyl-tRNA synthetases (aaRSs). These enzymes ligate an amino acid to a cognate tRNA and have proofreading and editing capabilities that ensure high fidelity. Phenylalanyl-tRNA synthetase (PheRS) preferentially ligates a phenylalanine to a tRNA^Phe over the chemically similar tyrosine, which differs from phenylalanine by a single hydroxyl group. In bacteria that undergo exposure to oxidative stress such as Salmonella enterica serovar Typhimurium, tyrosine isomer levels increase due to phenylalanine oxidation. Several residues are oxidized in PheRS and contribute to hyperactive editing, including against mischarged Tyr-tRNA^Phe, despite these oxidized residues not …

Tools And Strategies For The Patterning Of Bioactive Molecules And Macromolecules, Daniel J. Valles

Dissertations, Theses, and Capstone Projects

Hypersurface Photolithography (HP) is a printing method for fabricating structures and patterns composed of soft materials bound to solid surfaces and with ~1 micrometer resolution in the x, y, and z dimensions. This platform leverages benign, low intensity light to perform photochemical surface reactions with spatial and temporal control of irradiation, and, as a result, is particularly useful for patterning delicate organic and biological material. In particular, surface- initiated controlled radical polymerizations can be leveraged to create arbitrary polymer and block- copolymer brush patterns. Chapter 1 will review the advances in instrumentation architectures from our group that have made these …

Don't Sell Them Short, There's More To Bacterial Natural Products Than Antibiotics, Alison Clare Domzalski

Dissertations, Theses, and Capstone Projects

Recent genomic studies of microbiomes have revealed an overwhelming number of biosynthetic genes of unknown function. Most of these “cryptic” biosynthetic genes are not expressed in laboratory monocultures of individual microbes. Thus, there remains tremendous untapped potential for natural products discovery. Here we employ mixed microbial culture (MMC) as a simple yet powerful approach to awaken cryptic biosynthetic gene clusters. Our preliminary studies demonstrated that arrays of metabolites could be induced in MMCs upon environmental cues, such as surface adhesion. Using this system, we have screened, identified, and isolated bioactive bacterial metabolites, which were characterized structurally and biologically. Of the …

Automated Parsing Of Flexible Molecular Systems Using Principal Component Analysis And K-Means Clustering Techniques, Matthew J. Nwerem

Computational and Data Sciences (MS) Theses

Computational investigation of molecular structures and reactions of biological and pharmaceutical interests remains a grand scientific challenge due to the size and conformational flexibility of these systems. The work requires parsing and analyzing thousands of conformations in each molecular state for meaningful chemical information and subjecting the ensemble to costly quantum chemical calculations. The current status quo typically involves a manual process where the investigator must look at each conformation, separating each into structural families. This process is time-intensive and tedious, making this process infeasible in some cases, and limiting the ability of theoreticians to study these systems. However, the …

Design, Synthesis And Evaluation Of Molecules With Selective And Poly-Pharmacological Actions At D1r, D3r And Sigma Receptors, Pierpaolo Cordone

Dissertations, Theses, and Capstone Projects

The dopamine D3 receptor (D3R) is one of the most studied receptors involved in drug addiction. One of the most common strategies to treat substance use disorders is via D3R antagonism. The majority of the D3R antagonists synthesized so far have poor pharmacokinetic properties and/or lack selectivity toward D3R. In this thesis, the design, synthesis and biological evaluation of novel molecules that target the dopamine D1 receptor (D1R), D3R and the serendipitous discovery of molecules that target s receptors will be described.

Chapter 1 presents a survey of the fundamental pharmacology of D1R, D3R and s receptors and the therapeutic …

Reeling In New Antibiotics: Synthesis And Antimicrobial Susceptibility Testing Of Zinc-Binding Clavanins From Styela Clava (Sea Squirt), Eduardo Badillo-Colberg

Honors Scholar Theses

Clavanins have been a quite rarely studied antimicrobial peptide (AMP) family. Though the data in the few studies published on the matter and in theoretical experimental data presented by the Wang lab in their peptide library creation [14], in that the members of this family could potentially be quite effective novel antimicrobial candidates. Among those that have been targets of studies, Clavanin A has been at the forefront of this endeavor of finding effective novel antimicrobial peptides[14]. In these aforementioned studies, Clavanin A has been shown to be quite effective against many different bacterial strains, which begs the question as …

Visible Light Generation And Mechanistic Investigation Of High-Valent Metal-Oxo Species Supported By Different Ligands, Seth Ellis Klaine

Masters Theses & Specialist Projects

Numerous transition metal catalysts have been designed as biomimetic model compounds for the active site of metalloenzymes found throughout Nature, most notably cytochrome P450 monooxygenases that carry out the oxidative transformations of organic substrates with near-perfect chemo-, regio-, and stereo-selectivity. The primary active oxidants in catalytic and enzymatic cycles are fleeting high-valent metal-oxo intermediates where the oxo ligand can transfer to an organic substrate in a process known as oxygen atom transfer (OAT).

In the present work, porphyrin-manganese(III), salen-chromium(III), and salenmanganese( III) derivatives were successfully synthesized and spectroscopically characterized using 1H NMR and UV-Vis spectroscopies. A facile photochemical approach was …

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

Honors Theses

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

Methylation Of The D2 Dopamine Receptor Affects Binding With The Human Regulatory Proteins Par-4 And Calmodulin, Alexander Bowitch, Ansuman Sahoo, Andrea M. Clark, Christiana Ntangka, Krishna K. Raut, Paul Gollnick, Michael C. Yu, Steven M. Pascal, Sarah E. Walker, Denise M. Ferkey

Chemistry & Biochemistry Faculty Publications

No abstract provided.

Using The Marcus Inverted Region And Artificial Cofactors To Create A Charge Separated State In De Novo Designed Proteins, Eskil Me Andersen

Dissertations, Theses, and Capstone Projects

To create an efficient de novo photosynthetic protein it is important to create long lived charge separated states. Achieving stable charge separation leads to an increase in the efficiency of the photosynthetic reaction which in turn leads to higher yields of end products, such as biofuels, electrical charge, or synthetic chemicals. In an attempt to create charge separated states in de novo proteins we hypothesized that we could engineer the free energy gaps in the proteins from excited primary donor (PD) to acceptor (A), and A back to ground state PD such that the forward electron transfer (ET) would be …

Structual Analysis Of The Cl-Par-4 Tumor Suppressor As A Function Of Ionic Environment, Krishna K. Raut, Komala Ponniah, Steven M. Pascal

Chemistry & Biochemistry Faculty Publications

Prostate apoptosis response-4 (Par-4) is a proapoptotic tumor suppressor protein that has been linked to a large number of cancers. This 38 kilodalton (kDa) protein has been shown to be predominantly intrinsically disordered in vitro. In vivo, Par-4 is cleaved by caspase-3 at Asp-131 to generate the 25 kDa functionally active cleaved Par-4 protein (cl-Par-4) that inhibits NF-κB-mediated cell survival pathways and causes selective apoptosis in tumor cells. Here, we have employed circular dichroism (CD) spectroscopy and dynamic light scattering (DLS) to assess the effects of various monovalent and divalent salts upon the conformation of cl-Par-4 in vitro. We have …

Biocompatible And Multifunctional Trityl Spin Probes For Electron Paramagnetic Resonance Spectroscopy, Teresa D. Gluth

Graduate Theses, Dissertations, and Problem Reports (ETD)

The primary objective of my thesis was to develop and utilize a biocompatible multifunctional trityl spin probe for concurrent measurement of pO₂, pH_e, and [P_i] in vivo by electron paramagnetic resonance (EPR) spectroscopy (Chapter 2). My first goal was to synthesize the proposed probe we are terming HOPE71. Secondly, HOPE71 was characterized by X-band and L-band EPR spectroscopy. Next, the biocompatibility of HOPE71 was assessed through an albumin binding test, cytotoxicity assays, and in vivo intravenous tolerance. Then, the use of HOPE71 to measure the target parameters was demonstrated in a breast cancer …

Flavin Modification And Redox Tuning In The Bifurcating Electron Transfer Flavoprotein From Rhodopseudomonas Palustris: Two Arginines With Different Roles, Nishya Mohamed-Raseek

Theses and Dissertations--Chemistry

Electron bifurcation is considered as a third fundamental mode of energy conservation mechanism in addition to two well-known mechanisms, substrate level phosphorylation and Oxidative phosphorylation, in electron bifurcation endergonic and exergonic redox reactions are coupled. The newly discovered flavin based electron bifurcation in electron transfer flavoproteins (ETFs) helps to reduce low potential ferredoxin, which provides electrons to drive biologically demanding reactions such as atmospheric dinitrogen fixation in diazotroph and methane production in methanogens.

Current research demonstrates the capacity for electron bifurcation in the Rhodopseudomonas palustris ETF (RpalETF) system. RpalETF contains two chemically identical but functionally different FADs: …

Small Molecule Synthetic Carbohydrate Receptors, Marcelo F. Bravo Carranco

Dissertations, Theses, and Capstone Projects

Carbohydrate – receptor interactions are often involved in the attachment of viruses to host cells, and this docking is a necessary step in the virus life cycle that precedes infection and, ultimately, replication. Despite the conserved structures of the glycans involved in docking, they are still considered “undruggable”, meaning these glycans are beyond the scope of conventional pharmacological strategies. Recent advances in the development of synthetic carbohydrate receptors (SCRs) – small molecules that bind carbohydrates – could bring carbohydrate-receptor interactions within the purview of druggable targets. Here we discuss the role of carbohydrate-receptor interactions in viral infection, the evolution of …

Pressure Driven Desalination Utilizing Nanomaterials, Fangyou Xie

Master's Theses

Nanomaterials such as graphene oxide and carbon nanotubes, have demonstrated excellent properties for membrane desalination, including decrease of maintenance, increase of flux rate, simple solution casting, and impressive chemical inertness. Here, two projects are studied to investigate nanocarbon based membrane desalination. The first project is to prepare hybrid membranes with amyloid fibrils intercalated with graphene oxide sheets. The addition of protein amyloid fibrils expands the interlayer spacing between graphene oxide nanosheets and introduces additional functional groups in the diffusion pathways, resulting in increase of flux rate and rejection rate for the organic dyes. Amyloid fibrils also provide structural assistance to …

Toxicity Analysis Of 2’-Deoxyguanosine-N2-6-Aminopyrene And 2’-Deoxyguanosine-N2-8-Aminopyrene In Escherichia Coli, Emily Janeiro

Honors Scholar Theses

Cancer is a disease that stems from genomic errors that are not corrected properly by cellular repair mechanisms. Errors are more likely to form when organisms are subjected to DNA damage by mutagenic compounds. 1-Nitropyrene, a nitrated polycyclic aromatic hydrocarbon (nitro-PAH), has been shown to be a potent mutagen that causes cancer. Nitro-PAHs can arise from diesel exhaust products in the environment. Out of all nitro-PAHs, 1-nitropyrene is found in largest quantities in the environment. This poses a great need to study its effects biochemically in order to address its toxicity in DNA. Other nitropyrene derivatives, including 1,6-dinitropyrene and 1,8-dinitropyrene, …

Synthesized Tripodal Amine As Potential Anti-Cancer Therapeutic, Abigail G. Mcnamee

Honors College Theses

Cancer remains a prevalent disease today. This disease may manifest itself in many different ways and affect a variety of tissues with everything from the brain to the blood. With this wide diversity of cancer types, treatment can be complicated since there is not a “one size fits all” treatment for the disease. Surgery, radiation, and chemotherapy are all options that must be weighed with their benefits and side effects. Ultimately though, there are not enough effective treatment options available for every type of cancer. This leaves many with the grim prognosis of never being cured. With this clear need …

Development And Application Of Chemical Tools To Identify Kinase-Substrate Interactions, Aparni Kithulgoda Gamage

Wayne State University Dissertations

Post translational modifications regulate a variety of biological processes inside the cell.Protein phosphorylation is one such PTM modification catalyzed by protein kinases, which aid to transfer a signal from one place to another inside the cell. However, irregularities in kinase-mediated signaling are often implicated in many diseases, making kinases effective drug targets. To understand kinase-related disease formation and to discover drugs to treat these diseases, it is crucial to have a clear understanding on kinase-mediated cell signaling networks. A current gap in the kinase biology field is a lack of tools to identify which kinase phosphorylates which protein substrate inside …

Synthesis And The Genetic Encoding Of Novel Lysine Post-Translational Modifications, Sahan A. Galbada Liyanage

Theses and Dissertations

Post-translational modifications (PTMs) play a significant role in regulating cell signaling and regulating the inner cellular environment. The study of PTMs and their primary biological functions is critical for the development of new medicines targeting the pathways and biomolecules responsible for the PTMs.

Previous studies revealed the direct coupling of the β -hydroxybutyryl lysine (K_BHB) modification with the gene expression. K_BHB in histone proteins links metabolism to epigenetics and gene expression and enables to study in-depth, how cell metabolism controls the gene expression and vice versa. Similar novel histone modification, K_Lac, attracts a special interest …

Synthesis, Characterization, And Biological Activity Of Imidazolium Salts, David Weader

Williams Honors College, Honors Research Projects

Nonmuscle invasive bladder cancer (NMIBC) inflicts thousands of Americans annually, and is typically treated with the immunotherapy BCG. However, due to a BCG shortage, there is a new need for novel treatments of NMIBC. Addressing this issue, several imidazolium salt derivatives were synthesized and characterized with the intent of treatment within the bladder. These imidazolium salts were tested against different human bladder cancer cell lines in vitro to determine their reactivity and cytotoxicity. Among these results are GI50 concentrations for each drug, which is the concentration of drug needed to see growth inhibition in 50% of treated cells. Previous published …

Exploring Substrate Specificity Of Fructose Transporters En Route To Glut Specific Probes For Biochemical And Biomedical Applications, Vagarshak Vigenovich Begoyan

Dissertations, Master's Theses and Master's Reports

Carbohydrate Transporters (GLUTs) are responsible for the transportation of sugars into the cell and have been of great interest in research for decades. Alterations or mutations that result in overexpression of GLUTs have been linked to a great number of diseases including, obesity, diabetes, and cancer. Differentiation between transporters has been shown to be incredibly difficult due to the highly conserved nature of the transporter structure, and thus specific targeting of transporters has proven a difficult challenge. Additionally, the GLUTs have been shown to high flexibility in their conformations, so it is difficult to determine what can or cannot pass …

Asymmetric Synthesis Of The C29-C34 Moiety Of Fragment A Of The Antascomicin B & Thermal Azole Based Claisen Rearrangements, Dharma Theja Nannapaneni

Graduate Theses and Dissertations

The dissertation describes asymmetric synthesis towards C29-C34 moiety of fragment A of the Antascomicin B and Thermal azole based Claisen rearrangements. In chapter 1, we describes asymmetric synthesis towards C29-C34 moiety of fragment A of the Antascomicin B. The non-immunosuppressant Rapamycin, Ascomycin, and Tacrolimus (FK506), strongly binds with FKBP12, the ligand FKBP12 complexes responsible for immunosuppressive activity. Antascomicin B structurally related to Rapamycin, Ascomycin, and Tacrolimus (FK506), binds strongly to FKBP12, yet does not shown immunosuppressive activity. The ligand FKBP12 binding complexes shown to have potent neuroprotective and neurogenerative properties in mouse models of Parkinson’s disease. The linear synthesis of …