Organic Chemicals Commons^™

Mechanistic Studies And Derivative Effects In 1, 3, 4- Oxadiazole Synthesis Via Cyclodehydration Reactions, Evan Huggins

Undergraduate Honors Thesis Projects

In the world of pharmaceutical synthesis, research to combat foreign pathogens is always necessary. Scientists have been exploring different methods in order to synthesize the most effective compounds in antibacterial, anticancer, anti-inflammatory, and many other treatments. A key component within these versatile compounds are 1,3,4-oxadiazoles. Current methods to synthesize these compounds are inefficient. This research seeks to improve oxadiazole synthesis; however, the mechanism of this reaction is unknown. The goal of this project was to study the mechanistic pathway in the discovered, one-pot cyclodehydration synthesis of 1,3,4-oxadiazoles. In the first part of this study, a diacylhydrazine intermediate was proposed. This …

The Chemical Analysis And Biological Activities Of The Secondary Metabolites From Dalea Mollis And Dalea Albiflora, Nicholas Peter Hansen

All Master's Theses

Multidrug resistance has increased since the introduction of drugs used to prevent growth and kill microorganisms in a host. This has caused a worldwide search to discover new drugs effective against microorganisms. Mechanisms of drug resistance include, but are not limited to, the production of biofilms and efflux pumps. Efflux pumps prevent antimicrobial drugs from reaching their biological target, so the coordinated use of efflux pump inhibitors and antimicrobial drugs has been identified as a potential treatment for multidrug-resistant microorganisms. The secondary metabolites of Dalea mollis and Dalea albiflora were tested against multidrug-resistant (MDR) and engineered strains of the fungi …

1h And 13c Nmr Assignments For (N-Methyl)-(−)-(Α)-Isosparteinium Iodide And (N-Methyl)-(−)-Sparteinium Iodide, Kavoos Kolahdouzan, O. Maduka Ogba, Daniel J. O'Leary

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

(‒)-Sparteine (1) and (–)-(α)-isosparteine (2) are members of the lupine alkaloid family.^[1-2] Sparteine has found extensive use in asymmetric organic transformations, including lithiations^[3] and Pd-catalyzed oxidations.^[4-7] (α)-Isosparteine, which can be made from sparteine, has been utilized as a chiral ligand for a limited number of stereoselective reactions.^[8-9] The two compounds differ in that 1 displays an exo-endo arrangement of the bridgehead hydrogens at C-11 and C-6, respectively, while 2 retains an exo-exo arrangement of these atoms (Figure 1). This study is focused on assigning 1H chemical shifts and coupling constants and 13C chemical shifts for N-methyl …

Photochemical Investigation Of High-Valent Metal-Oxo Intermediates Containing Corrole And Light-Harvesting Porphyrin Ligands, Jonathan Malone

Masters Theses & Specialist Projects

In enzymatic and synthetic catalytic oxidations, high-valent iron-oxo intermediates play a vital role as the active oxidant. In this regard, many synthetic metal catalysts are designed as biomimetic models to resemble the active site of Cytochrome P450 enzymes (P450) which are the predominant oxidation catalysts in nature. Vitamin B12 cofactors, with a corrole-like structure corrin, are also utilized in some of the more difficult reactions in nature such as rearrangement and reductase reactions.

In this work, application of the promising photochemical method to corrolecontaining ligands systems showed much success in the generation of manganese(V)-oxo corrole intermediates using two electron-deficient corrole …

Do Paraben Derivatives Alter T Cell Immunity?, Hailey Kintz

Spring Presentation of Undergraduate Research

T cells immunity is linked to a complex system of cytokines that determine differentiation of naïve T cells into Th1, Th2, Th17, and Treg cells. Estrogen production or periods of elevated production have been correlated with an anti-inflammatory state in which Th2 and Treg cells are up-regulated. Such responses in the immune system are capable of supporting pre-cancerous activity. We are investigating the tie between the xenoestrogen compounds found in cosmetics, parabens, and their ability to regulate T cell immunity. Testing parabens and paraben derivatives with weaker estrogen receptor association will allow for a better understanding of the interplay between …

Cellular And Molecular Targets Of Menthol Actions, Murat Oz, Eslam El Nebrisi, Keun-Hang Susan Yang, Frank Christopher Howarth, Lina T. Al Kury

Mathematics, Physics, and Computer Science Faculty Articles and Research

Menthol belongs to monoterpene class of a structurally diverse group of phytochemicals found in plant-derived essential oils. Menthol is widely used in pharmaceuticals, confectionary, oral hygiene products, pesticides, cosmetics, and as a flavoring agent. In addition, menthol is known to have antioxidant, anti-inflammatory, and analgesic effects. Recently, there has been renewed awareness in comprehending the biological and pharmacological effects of menthol. TRP channels have been demonstrated to mediate the cooling actions ofmenthol. There has been new evidence demonstrating thatmenthol can significantly influence the functional characteristics of a number of different kinds of ligand and voltage-gated ion channels, indicating that at …

Synthesis Of Multifunctional Polyacrylates And A Binding Group To Hemoglobin For The Treatment Of Traumatic Brain Injuries, Marina Michaud

Honors College Theses

Hemoglobin based oxygen carriers (HBOCs) hold promise as an effective emergency treatment of severe traumatic brain injuries (TBI). In the latest generation of HBOCs, polynitroxyl-pegylated hemoglobin (PNPH), cell-free hemoglobin is modified with TEMPO and PEG which reduce the toxicities associated with earlier generations of HBOCs. In our efforts to optimize the economic and therapeutic impacts of PNPH’s we have synthesized polydimethylaminoethyl methacrylate (poly-DMAEMA) under controlled living conditions via reverse addition-fragmentation chain transfer (RAFT) polymerization. The poly-DMAEMA was then successfully functionalized via quaternization of its NMe₂ groups using chloroacetate derivatives of the TEMPO and PEG. This process was quantitative and …

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

All Master's Theses

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

Assembly Of Nucleic Acid-Based Nanoparticles By Gas-Liquid Segmented Flow Microfluidics, Matthew L. Capek, Ross Verheul, David H. Thompson

The Summer Undergraduate Research Fellowship (SURF) Symposium

The development of novel and efficient mixing methods is important for optimizing the efficiency of many biological and chemical processes. Tuning the physical and performance properties of nucleic acid-based nanoparticles is one such example known to be strongly affected by mixing efficiency. The characteristics of DNA nanoparticles (such as size, polydispersity, ζ-potential, and gel shift) are important to ensure their therapeutic potency, and new methods to optimize these characteristics are of significant importance to achieve the highest efficacy. In the present study, a simple segmented flow microfluidics system has been developed to augment mixing of pDNA/bPEI nanoparticles. This DNA and …

The Synthesis Of 1,3-Difluoro-2-Methyl-4-Phenylbenzene From A One-Pot Reaction Of Difluorocarbene And 1-Phenyl-2-Methylcyclobutene, Ruth Felicitas Menger

Senior Honors Projects, 2010-2019

Previous studies show that 1,2-disubstituted cyclobutenes can be used in reaction with difluorocarbene to produce 1,3-difluorobenzenes. A pathway to the synthesis of these types of compounds is of interest due to their presence in fluoroquinolone antibacterials, resins, and insecticides. The synthesis is unique because the fluorine atoms from the difluorocarbene are not adjacent to each other when the ring expands to a benzene ring. This study focuses on the reaction of difluorocarbene with 1-phenyl-2-methylcyclobutene, which was synthesized in one-pot in 4 steps starting from 1-phenyl-1-propyne and zirconocene dichloride.

Probing Allosteric, Partial Inhibition Of Thrombin Using Novel Anticoagulants, Stephen S. Verespy Iii

Theses and Dissertations

Thrombin is the key protease that regulates hemostasis; the delicate balance between procoagulation and anticoagulation of blood. In clotting disorders, like deep vein thrombosis or pulmonary embolism, procoagulation is up-regulated, but propagation of clotting can be inhibited with drugs targeting the proteases involved, like thrombin. Such drugs however, have serious side effects (e.g., excessive bleeding) and some require monitoring during the course of treatment. The reason for these side effects is the mechanism by which the drugs’ act. The two major mechanisms are direct orthosteric and indirect allosteric inhibition, which will completely abolish the protease’s activity. Herein we sought an …

The Synthesis And Study Of The Biological And Colloidal Properties Of Bolaamphiphiles, Louis M. Damiano

Senior Honors Projects, 2010-2019

Over the past decade, antibiotic resistant bacteria have caused infections in patients throughout the world.^[1] The rise in antibiotic resistance is primarily due to the misuse and overuse of antibiotics. ^[1] To counter the increase in antibiotic resistance, infection control mechanisms have been aggressively researched in recent years. In particular, drug delivery has become a focal point to fight antibiotic resistant infections.^[2] Amphiphiles have a wide range of applications in the clinical setting, including the ability to inhibit bacterial transference because of their bactericidal activity. ^[3] Bolaamphiphiles are a subclass of amphiphiles that possess two or more hydrophilic …

Total Synthesis Of Biologically Active Natural And Unnatural Products, Julia Heimberger

College of Graduate Studies: Theses & Dissertations

Herbarin A and B were isolated from the fungal strains of Cladosporium herbarum found in marine sponges Aplysina aerophoba and Callyspongia aerizusa. Total synthesis of Herbarin A and B was achieved by carrying out a multi-step synthesis approach, and the antioxidant properties were evaluated using FRAP assay. Toxicity of these compounds was determined using a zebrafish embryo model. Furthermore, synthesis of C-6 alkyl-azaarene derivatives of nucleosides by Csp3-H bond functionalization were investigated. Effective incorporation of 2-methylazaarene moiety at the C-6 position of the protected inosine nucleoside provided a new class of compounds with anticipated enhanced biological activity.

Chemoenzymatic Studies To Enhance The Chemical Space Of Natural Products, Jhong-Min Chen

Theses and Dissertations--Pharmacy

Natural products provide some of the most potent anticancer agents and offer a template for new drug design or improvement with the advantage of an enormous chemical space. The overall goal of this thesis research is to enhance the chemical space of two natural products in order to generate novel drugs with better in vivo bioactivities than the original natural products.

Polycarcin V (PV) is a gilvocarcin-type antitumor agent with similar structure and comparable bioactivity with the principle compound of this group, gilvocarcin V (GV). Modest modifications of the polyketide-derived tetracyclic core of GV had been accomplished, but the most …

Design, Synthesis And Biological Evaluation Of Novel Compounds With Cns-Activity Targeting Cannabinoid And Biogenic Amine Receptors, Alexander M. Sherwood

University of New Orleans Theses and Dissertations

This work seeks to contribute to the discipline of neuropharmacology by way of structure activity relationship from the standpoint of an organic chemist. More specifically, we sought to develop robust synthetic methodology able to efficiently produce an array of compounds for the purpose of systematic evaluation of their interaction with specific sights within the central nervous system (CNS) in order to better understand the mind and to develop drugs that may have beneficial effects on neurological function.

The focus of these studies has been toward the development of novel molecules, using a structure-activity relationship approach, that exhibit binding affinity at …

Polyethylene Glycol Containing Rompolymers For The Modification Of Neuro-Protective Hemoglobin, Andrea L. Mccollum

Honors College Theses

Polyethylene glycol (PEG) has shown the ability to improve compatibility when used in combination with cell-free hemoglobin in the treatment of traumatic brain injuries. It has been demonstrated that the covalently bonded PEG increases the hydrodynamic radius of the hemoglobin and hence generates a physical barrier while slowing down the oxygen delivery of the strongly oxidative hemoglobin. In this context, I have been working on the development of synthetic pathways to incorporate PEG into monomers and polymers through both direct modification of (7-oxa)norbornene derivatives and post polymerization modification. Starting from the (7-oxa)norbornene anhydride derivatives, we have developed pathways to cationic …

The Reaction Of Methionine With A Non-C2-Symmetrical Platinum (Ii) Diamine Compound, Nilesh Sahi

Mahurin Honors College Capstone Experience/Thesis Projects

The research that we have conducted has allowed us to discover that the amino acids, methionine (Met) and N-acetyl methionine (N-AcMet), will react in a 1:1 and 1:2 molar ratio with platinum complexes containing bulky diamine ligands. Previous research has allowed us to gain a plethora of information on the experimentation and results of specific bulky diamine ligands such as N,N,N',N'-tetramethylethylenediamine and N,N-diethylethylenediamine. In the current study, we have investigated the bulky diamine ligand of N,N-dimethylethylenediamine, or Me₂en. With our focus on the bulk of the Me₂en ligand, we have been able to synthesize a platinum …

Bulletin 4307 - Grass Control In Pastures Using Herbicides, Alexandra Wallace

Bulletins 4000 -

This Bulletin discusses three methods for herbicide control of grasses in pastures:

• pasture manipulation, in the early stages of pasture growth;
• spray-topping late in the growing season; and
• hay freezing, late in the growing season.

The Isolation And Identification Of Polyphenolics From Grape Seeds And Their Activity Towards Specific Cell Lines, Joseph A. Reddy

Chemistry & Biochemistry Theses & Dissertations

Grape seed extract is being marketed in France for cardiovascular use and skin care. The active constituents of both these drugs are certain polyphenols called procyanidins. A similar seed extract has now been obtained from Virginia Chardonnay grape seeds. Ten of the major components in this extract have been isolated in their pure form by the semi-preparative HPLC separation on a YMC ODS-AQ (Octadecylsilane-AQ) column. The ODS-Aq column has been shown to have a better resolving capacity compared to the Spherisorb ODS (Octadecylsilane) column previously described in the literature. This has been attributed to the ODSAQ support which has both …

The Synthesis And Evaluation Of The Cardiovascular Activity Of Novel Imidazole Ring Systems, Joseph E. De Los Angeles

Chemistry & Biochemistry Theses & Dissertations

An investigation was undertaken to synthesize and evaluate the cardiovascular activity of two imidazole ring systems. Imidazoles with hypotensive activity would provide novel potential antihypertensive drugs. These novel structures may also find use as chemical probes in the study of the cardiovascular system and as prototypes for other potential cardiovascular agents.

The histamine derivative, 7,7-dipyridyl-4,5,6,7-tetrahydroimidazo-[4,5-c]pyridine (ligand l), was demonstrated to possess significant hypotensive activity in laboratory rats. A 15 mg/Kg dose of ligand 1 produces a statistically significant decrease in blood pressure when injected IP. This hypotensive effect is also associated with marked increase in heart rate. Although compound 1 …