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N-Bridged Dimers Of Tetrapyrroles Complexed By Transition Metals: Syntheses, Characterization Methods, And Uses As Oxidation Catalysts, Ümi̇t İşci̇, Fabienne Dumoulin, Alexander B. Soroki̇n, Vefa Ahsen

Turkish Journal of Chemistry

N-bridged dimers of tetrapyrroles complexed by transition metals have been known for nearly four decades, and gained renewed attention when their powerful oxidation properties were recently evidenced. This article is a state of the art review of the reported complexes and of their synthetic methods. Beyond classical chemistry characterization tools, specific methods appropriate to their structure are used and are presented in detail. Finally, their uses and importance of oxidation catalysts are reviewed.

Boron-Containing Tetrapyrroles, Şennur Özçeli̇k, Ahmet Gül

Turkish Journal of Chemistry

The recent advances in the synthesis of carborane and boronic ester-substituted tetrapyrroles (porphyrins, porphyrazines, and phthalocyanines) are reviewed together with their possible utilization as agents for photodynamic therapy (PDT) and boron neutron capture therapy of cancer (BNCT) as well as dual PDT/BNCT sensitizers.

Td-Dft Calculations And Mcd Spectroscopy Of Porphyrin And Phthalocyanine Analogues: Rational Design Of Photosensitizers For Pdt And Nir Region Sensor Applications, John Mack, Martijn Wildervanck, Tebello Nyokong

Turkish Journal of Chemistry

Geometry optimizations and TD-DFT calculations have been carried out on series of fused-ring-expanded phthalonitriles, phthalocyanines, and aza-dipyrromethene boron difluoride (aza-BODIPY) dyes and trends in their optical and redox properties have been analyzed. The potential utility of fused-ring-expanded phthalocyanine and aza-BODIPY analogues for photodynamic therapy and near infrared region sensor applications is assessed on this basis. Recent attempts to prepare fused-ring-expanded aza-BODIPY analogues with benzene, pyrazine, and naphthalene rings have demonstrated that the properties of aza-BODIPYs vary markedly when different fused ring systems are added to the \beta-carbons of the pyrrole rings. A comparison of the TD-DFT calculations demonstrates that, as …

New Soluble Amidoamine Substituted Phthalocyanines: Synthesis, Characterization, And Investigation Of Their Solution Properties, Senem Çolak, Sali̇h Zeki̇ Yildiz

Turkish Journal of Chemistry

The synthesis of tetraaminopropylamid substituted phthalocyanines was targeted to prepare enhanced soluble phthalocyanines in common solvents from hydrophobic to hydrophilic that bore nonionic groups on their periphery. Metal-free (H_2Pc) and metallophthalocyanines (Zn(II) (ZnPc), Cu(II) (CuPc) and Co(II) (CoPc)) were prepared and characterized by UV-Vis, FT-IR, and mass spectroscopies. The ^1H NMR spectra were recorded for the diamagnetic phthalocyanine species H_2Pc and ZnPc. The phthalocyanines showed sufficient solubility in common organic solvents such as dimethyl sulfoxide, tetrahydrofuran, and ethanol. However, methanol was not a good solvent for CuPc and H_2Pc. Solubility and aggregation studies of H_2Pc and ZnPc were performed in …

Murchison Chondrite, Marisol Chirinos

Natural Sciences Student Research Presentations

Murchson Chondrite is a carbonaceous meteorite that fell in a small town called Murchson in Victoria, Australia, on September 28, 1969. It is believed to be one of the most primitive meteorites to fall on earth. Amino acides found in Murchison differ in structures from amino acids found on Earth. While the carbon atom in the carboxylic acid and amion group of biological terrestrial amino acids have a hydrogen atom attached to it, the Murchison's amino acids have a methyl group instead.

An Inexpensive, Temporally Integrated System For Monitoring Occurrence And Biological Effects Of Aquatic Contaminants In The Field, Michael D. Kahl, Daniel L. Vileneuve, Kyle Stevens, Anthony Schroeder, Elizabeth A. Makynen, Carlie A. Lalone, Kathleen M. Jensen, Meagan Hughes, Bruce A. Holmen, Evan Eid, Elizabeth J. Durhan, Jenna E. Cavallin, Jason Berninger, Gerald T. Ankley

United States Environmental Protection Agency: Publications

Assessment of potential risks of complex contaminant mixtures in the environment requires integrated chemical and biological approaches. In support of the US Great Lakes Restoration Initiative, the US Environmental Protection Agency lab in Duluth, MN, is developing these types of methods for assessing possible risks of aquatic contaminants in near-shore Great Lakes (USA) sites. One component involves an exposure system for caged fathead minnow (Pimephales promelas) adults suitable for the wide range of habitat and deployment situations encountered in and around the Great Lakes. To complement the fish exposure system, the authors developed an automated device for collection of composite …

Noncovalent Interactions Involving Microsolvated Networks Of Trimethylamine N-Oxide, Kristina Andrea Cuellar

Electronic Theses and Dissertations

This thesis research focuses on the effects of the formation of hydrogen-bonded networks with the important osmolyte trimethylamine N-oxide (TMAO). Vibrational spectroscopy, in this case Raman spectroscopy, is used to interpret the effects of noncovalent interactions by solvation with select hydrogen bond donors such as water, methanol, ethanol and ethylene glycol in the form of slight changes in vibrational frequencies. Spectral shifts in the experimental Raman spectra of interacting molecules are compared to the results of electronic structure calculations on explicit hydrogen bonded molecular clusters. The similarities in the Raman spectra of microsolvated TMAO using a variety of hydrogen bond …

Structural Analysis Of Bulky Thiolate-Protected Gold Nanomolecules, David Walton Crasto

Electronic Theses and Dissertations

Routine preparation of thiolate-protected gold nanomolecules involves, most commonly, straight-chain organic thiolate ligands for which the sulfhydryl `head' group is bound to a primary carbon atom. The primary connectivity of these sulfur atoms, such as for the case of n-hexanethiol and phenylethanethiol, allows for even packing, and the relative ease of formation of gold-thiolate oligomers about the surface monolayer in the formation of Au-SR bonds. Moreover, these straight-chain ligands routinely support the formation of an icosahedron-based series of core-size gold nanomolecules. Within this series of nanoparticles, Au25(SR)18 and Au38(SR)24 are among the most commonly studied core-sizes; Au25(SR)18 is situated upon …

Gold-Magnetite Nanoparticle-Biomolecule Conjugates: Synthesis, Properties And Toxicity Studies, Akshay Pariti

Masters Theses

"This thesis study focuses on synthesizing and characterizing gold-magnetite optically active magnetic nanoparticle and its conjugation with biomolecules for biomedical applications, especially magnetic fluid hyperthermia treatment for cancerous tissue. Gold nanoparticles have already displayed their potential in the biomedical field. They exhibit excellent optical properties and possess strong surface chemistry which renders them suitable for various biomolecule attachments. Studies have showed gold nanoparticles to be a perfect biocompatible vector. However, clinical trials for gold mediated drug delivery and treatment studied in rat models identified some problems. Of these problems, the low retention time in bloodstream and inability to maneuver externally …

Approximate Quantum Trajectory Method For Modeling Chemical Reaction Dynamics: Application To Enzymatic Proton Transfer, James William Mazzuca

Theses and Dissertations

Molecular dynamics simulations, providing a detailed picture of the reaction mechanism, is an essential tool for theoretical and experimental chemists. In these simulations the nuclei are typically treated as classical particles, but under some conditions (low energies and temperatures, processes involving multiple electronic states) a classical description is inappropriate. Quantum effects of nuclear motion, such as tunneling and zero-point energy can play an important role in determining a reaction mechanism, yet exact quantum dynamics methods are limited to reactive systems of just 3-4 atoms. Central to this work is the development and implementations of an efficient trajectory-based methodology, in which …

The Role Of Potential Antioxidant In Medicinal Drug-Induced Oxidative Stress, Weili Fan

Doctoral Dissertations

"Most medicinal drugs have adverse effects. Among the most commonly used of these drugs are several types, known as "oxidative drugs". These are believed to cause adverse effects that induce oxidative stress, an imbalance of generation and detoxification of reactive oxygen species. So it is a reasonable assumption that the antioxidant might alleviate the toxicity induced by these drugs. N-acetylcysteine (NAC), a synthetic thiol, is a free-radical scavenger and a precursor of glutathione (the main endogenous antioxidant). However, the negative charge of NAC at physiological pH limits its bioavailability. N-acetylcysteineamide (NACA) is neutral in charge and is believed to have …

Part I: In-Situ Fluorometric Quantification Of Microalgal Neutral Lipids Part Ii: Thermal Degradation Behavior Of Investment Casting Polymer Patterns, Hongfang Zhao

Doctoral Dissertations

"Research described in this dissertation covers two topics. Part-I is focused on in-situ determination of neutral lipid content of microalgae using a lipophilic fluorescent dye. The traditional Nile red stain-based method for detecting microalgal intracellular lipids is limited due to varying composition and thickness of rigid cell walls. In this study, the addition of dilute acid and heating of solution, were found to greatly enhance staining efficiency of Nile red for microalgal species evaluated. Oil-in-water (O/W) microemulsion stabilized by a non-ionic surfactant was employed as a pseudo-standard that mimics lipid-bearing microalgal cells suspended in water. The average neutral lipid contents …

Semiconductor Nanocrystals For Novel Optical Applications, Jong-Sik Moon

Doctoral Dissertations

“Inspired by the promise of enhanced spectral response, photorefractive polymeric composites photosensitized with semiconductor nanocrystals have emerged as an important class of materials. Here, we report on the photosensitization of photorefractive polymeric composites at visible wavelengths through the inclusion of narrow band-gap semiconductor nanocrystals composed of PbS. Through this approach, internal diffraction efficiencies in excess of 82%, two-beam-coupling gain coefficients in excess of 211 cm^-1, and response times 34 ms have been observed, representing some of the best figures-of-merit reported on this class of materials. In addition to providing efficient photosensitization, however, extensive studies of these hybrid composites …

Structure Vs. Properties Using Chemical Graph Theory, Tabitha N. Williford

College of Graduate Studies: Theses & Dissertations

Chemical graph theory began as a way for mathematicians to bring together the areas of the Physical Sciences and Mathematics. Through its use, mathematicians are able to model chemical systems, predict their properties as well as structure-property relationships. In this dissertation, we consider two questions involving chemical graph theory and its applications. We first look at tree-like polyphenyl systems, which form an important family of compounds in Chemistry, particularly in Material Science. The importance can be seen in LEDs, transmitters, and electronics. In recent years, many extremal results regarding such systems under specific constraints have been reported. More specifically are …

Synthesis Of 4'-O-Glycopyranosyl Paromomycin Aminoglycoside Antibiotics: Influence Of The Glycoside On Antiribosomal, Antibacterial Activity And Utilization Of Electrospray Ionization Mass Spectrometry To Evaluate Reactivity Of Glycosyl Phosphate, Weiwei Chen

Wayne State University Theses

The data in this thesis is trying to address two problems. The first problem is paromomycin associated ototoxicity; the second problem is the lack of precise reactivity data of glycosyl donors in one-pot synthesis.

Paromomycin is out of the market as an antibiotic due to its ototoxicity. Previous work done by Vasella and Böttger's groups identified 4'-O position of paromomycin as a promising site of modification to reduce the side effect. A series of 4'-O-glycopyranosyl paromomycin has been synthesized and tested for their biological activity and selectivity. From the results of anti bacterial ribosomal activity, anti hybrid ribosomal activity and …

Biophysical Studies Of Mutant H69 Rna Constructs, Daya Nidhi Kharel

Wayne State University Theses

The importance of helix 69 (H69) of the large ribosomal subunit is emphasized by its location in the ribosome and key contacts with protein factors and tRNAs during different steps of protein synthesis. The presence of three highly conserved pseudouridine modifications in H69 has a significant impact on modulation of the ribosome conformations. Specific nucleotides of H69 may be necessary for the function of this helix-loop RNA, as some mutations are deleterious to bacterial growth. In this study, we investigated the effects of single nucleotide mutations in a 19-nucleotide H69 construct with and without pseudouridines on the RNA stability and …

Genetic And Biochemical Studies Of Human Apobec3h Enzyme, Thisari Sachithra Aluthgama Guruge

Wayne State University Theses

The AID/APOBEC enzymes are DNA/RNA cytosine deaminases with important functions in innate and adaptive immunity. APOBEC3 enzymes play a crucial role in restricting the replication of exogenous retroviruses such HIV-1 and endogenous retrotransposition events. In particular, APOBEC3 enzymes have evolved in humans by gene duplication to compose seven members. APOBEC3H is highly diverse in its allelic sequence and the distribution is population-specific. It has evolved under strong positive selection over millions of years. To study the catalytic mechanism, structure, function and the underlying cause of its high diversity, a high resolution crystal or NMR structure is required are not yet …

Synthesis And Characterization Of Brain Penetrant Prodrug Of Neuroprotective D264: Potential Disease Modifying Treatment Agent For Parkinson's Disease, Fahd Shamoon Dholkawala

Wayne State University Theses

Parkinson's disease (PD) is a complex neurodegenerative disorder with progressive loss of dopamanergic neurons in the substantia nigra region of the brain and accumulation of intracytoplasmic inclusions called `Lewy bodies'. PD is characterized by tremors, rigidity, slowness of movement, bradykinesia and postural imbalances. Although the etiology of PD is not well understood, it is well established that oxidative stress, mitochondrial dysfunction, alpha-synuclein aggregation play a central role in the pathogenesis of PD. Current treatment methods are based on symptomatic relief without addressing the underlying pathophysiological factors responsible for the disease. It is important to develop therapies which can address these …

The Ph Dependence Of Photosystem Ii Oxygen-Evolving Complex Assembly, Emilee Hope Cook

Theses, Dissertations and Capstones

Photosystem II (PSII) research has gained interest in recent years due to the need for energy production. However the mechanisms of photosystem II photoassembly and water oxidation are not well understood. Therefore the main goal of my research was to understand photoassembly better by determining the pH dependence of oxygen evolving complex (OEC) assembly. These experiments could help to gain a better understanding of D1 (a subunit of photosystem II) degradation and PSII repair as well as determine the amino acid residues involved in the process. However, we had several issues with photoassembly along the way that had to be …

Molecular Characterization And Photochemical Transformation Of Dissolved Organic Matter From Land To Ocean, Hongmei Chen

Chemistry & Biochemistry Theses & Dissertations

Molecular characterization and photochemical transformation of dissolved organic matter (DOM) in both rivers and the ocean is the main research focus of this dissertation. Chemical characterization of DOM is hampered by the limited application of advanced techniques to desalt, concentrate, isolate and then molecularly characterize DOM. An affordable, commercially available mini-electrodialysis (mini-ED) system has been evaluated and recommended for the efficient desalting of small volume samples of seawater prior to analysis by electrospray Fourier transform ion cyclotron resonance mass spectrometry (ESI FTICR-MS).

A high-recovery technique of DOM isolation – reverse osmosis coupled with electrodialysis (RO/ED) – was used to isolate …

Cellulose-Chitosan-Keratin Composite Materials: Synthesis, Immunological And Antibacterial Properties, Meghann Rosewald, Fang Yao Stephen Hou, Tamutsiwa Moven Mututuvari, April L. Harkins, Chieu D. Tran

Chemistry Faculty Research and Publications

Novel composites were synthesized from keratin (KER), cellulose (CEL) and chitosan (CS). The method is recyclable because majority (>88%) of [BMIm⁺Cl^-], an ionic liquid (IL), used as the sole solvent, was recovered for reuse. Experimentally, it was confirmed that unique properties of each component remain intact in the composites, namely bactericide (from KER and CS) and anti-inflammatory property (from KER). Specifically, the composites were examined for their anti-inflammatory influence on macrophages. The cells were imaged and immunophenotyped to determine the quantity using the macrophage marker CD11b. The 75:25 [KER+CS] composite was found to have the …

On Readout Of Vibrational Qubits Using Quantum Beats, Dmytro Shyshlov, Eduardo Berrios, Martin Gruebele, Dmitri Babikov

Chemistry Faculty Research and Publications

Readout of the final states of qubits is a crucial step towards implementing quantum computation in experiment. Although not scalable to large numbers of qubits per molecule, computational studies show that molecular vibrations could provide a significant (factor 2–5 in the literature) increase in the number of qubits compared to two-level systems. In this theoretical work, we explore the process of readout from vibrational qubits in thiophosgene molecule, SCCl₂, using quantum beat oscillations. The quantum beats are measured by first exciting the superposition of the qubit-encoding vibrational states to the electronically excited readout state with variable time-delay pulses. …

Synthesis And Spectroscopic Characterization Of High-Spin Mononuclear Iron(Ii) P-Semiquinonate Complexes, Amanda E. Baum, Heaweon Park, Sergey V. Lindeman, Adam T. Fiedler

Chemistry Faculty Research and Publications

Two mononuclear iron(II) p-semiquinonate (pSQ) complexes have been generated via one-electron reduction of precursor complexes containing a substituted 1,4-naphthoquinone ligand. Detailed spectroscopic and computational analysis confirmed the presence of a coordinated pSQ radical ferromagnetically coupled to the high-spin FeII center. The complexes are intended to model electronic interactions between (semi)quinone and iron cofactors in biology.

Isomer Dependence In The Assembly And Lability Of Silver(I) Trifluoromethanesulfonate Complexes Of The Heteroditopic Ligands, 2-, 3-, And 4-[Di(1H-Pyrazolyl)Methyl]Phenyl(Di-P-Tolyl)Phosphine, James R. Gardinier, Jeewantha S. Hewage, Sergey V. Lindeman

Chemistry Faculty Research and Publications

Three isomers of a new heteroditopic ligand that contains a di(1H-pyrazolyl)methyl (−CHpz₂) moiety connected to a di(p-tolyl)phosphine group via a para-, meta-, or ortho-phenylene spacer (pL, mL, and oL, respectively) have been synthesized by using a palladium(0)-catalyzed coupling reaction between HP(p-tolyl)₂ and the appropriate isomer of (IC₆H₄)CHpz₂. The 1:1 complexes of silver(I) trifluoromethanesulfonate, Ag(OTf), were prepared to examine the nature of ligand coordination and the type of supramolecular isomer (monomeric, cyclic oligomeric, or polymeric) that would be obtained. …

Preparation Of Polylactide/ Polycaprolactone/Hydroxyapatite Particles, Walaiporn Nguantanom

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research focused on preparation of polylactide/polycaprolactone/hydroxyapatite particles by using the solvent evaporation method. The effects of HA loadings varied in a range of 10-40 wt% and blending ratios between PLA and PCL on the size distribution, morphology, and thermal properties of the composite films were investigated. The results showed that the size distributions of the composite particles were composed of both small and large particles, depending on the HA concentration and blending ratio of PLA/PCL. The addition of HA at 10 wt% exhibited a strong influence on the size distribution of microspheres, while the PLA/PCL blend tended to produce …

Mechanical And Thermal Properties Of Polylactide/Polymeric Plasticizers, Wanlapha Apising

Chulalongkorn University Theses and Dissertations (Chula ETD)

The current study focused on flexibility improvement of polylactide by using three new types of plasticizers: diethyl succinate, glycerol ethoxylate, poly(di(ethylene glycol)adipate). The plasticizer concentrations were varied depending on each type. Mechanical property of the plasticized polymers was investigated. It was found that elongation at break of the plasticized polymers was increased, whereas tensile strength and Young’s modulus were decreased. The plasticized polymer with diethyl succinate exhibited the highest elongation at break. Thermal property of the plasticized polymers containing glycerol ethoxylate yielded the lowest Tg and Tc. When the plasticizers were added, thermal property was reduced, in which the plasticized …

Biochemical Characterization Of Four Distinct Proteins, Gustavo A. Avila

Open Access Theses & Dissertations

Proteins are ubiquitous in all living organisms, executing the majority of cellular functions in distinct ways. Understanding a protein's role necessitates investigating its structure and function, which are closely related. My research couples these two aspects by delving into the biochemical and structural characterization of proteins in four distinct systems, all playing central roles in numerous significant disease progressions. These four original research endeavors were all targeted for structural studies with a unifying relationship to establish our new structural biochemistry lab. These four systems are: (1) Gam1, an early adenovirus protein globally inhibiting host SUMOylation; (2) Anthrax toxin complexed with …

Glyco-Modification Of Protein With O-Cyanate Chain-End Functionalized Glycopolymer Via Isourea Bond Formation, Valentinas Gruzdys, Hailong Zhang, Xue-Long Sun

Chemistry Faculty Publications

Glycoengineering aimed at addition of carbohydrates to proteins is an attractive approach to alter pharmacokinetic properties of proteins such as enhancing stability and prolonging the duration of action. We report a novel protein glyco-modification of BSA and recombinant thrombomodulin with O-cyanate chain-end functionalized glycopolymer via isourea bond formation. The protein glycoconjugates were confirmed by SDS-PAGE, western blot, and MALDI-TOF Mass Spectrometry. Protein C activation activity of the glyco-modified recombinant thrombomodulin was confirmed, proving no interference to activity from the glycopolymer modification. The isourea bond formation under mild conditions was demonstrated as an alternative method for protein modification with polymers.

Wavelength And Temperature-Dependent Apparent Quantum Yields For Photochemical Formation Of Hydrogen Peroxide In Seawater, David J. Kieber, Gary W. Miller, Patrick J. Neale, Kenneth Mopper

Chemistry & Biochemistry Faculty Publications

Wavelength and temperature-dependent apparent quantum yields (AQYs) were determined for the photochemical production of hydrogen peroxide using seawater obtained from coastal and oligotrophic stations in Antarctica, the Pacific Ocean at Station ALOHA, the Gulf of Mexico, and at several sites along the East Coast of the United States. For all samples, AQYs decreased exponentially with increasing wavelength at 25 °C, ranging from 4.6 × 10−4 to 10.4 × 10−4 at 290 nm to 0.17 × 10−4 to 0.97 × 10−4 at 400 nm. AQYs for different seawater samples were remarkably similar irrespective of expected differences in the composition and concentrations …

Synthesis And Characterization Of Ph Responsive D-Glucosamine Based Molecular Gelators, Navneet Goyal, Hari P.R. Mangunuru, Bargav Parikh, Sonu Shrestha, Guijun Wang

Chemistry & Biochemistry Faculty Publications

Small molecular gelators are a class of compounds with potential applications for soft biomaterials. Low molecular weight hydrogelators are especially useful for exploring biomedical applications. Previously, we found that 4,6-O-benzylidene acetal protected D-glucose and D-glucosamine are well-suited as building blocks for the construction of low molecular weight gelators. To better understand the scope of D-glucosamine derivatives as gelators, we synthesized and screened a novel class of N-acetylglucosamine derivatives with a p-methoxybenzylidene acetal protective group. This modification did not exert a negative influence on the gelation. On the contrary, it actually enhanced the gelation tendency for many derivatives. The …