Fluorescence of adenine, guanine, thymine, cytosine, and uracil
has been detected at room temperature in neutral aqueous solution
using a digital signal accumulation technique and right angle fluorescence
detection from solutions with absorbances between 0. 4 and 0. 7.
The quantum yields are respectively 2.6 x 10⁻⁴, 3.0 x 10⁻⁴,...
The photolysis of the aqueous thymine system has been investigated
at 214 nm, 229 nm and 254 nm at room temperature. Products
of photolysis have been identified as hydrogen peroxide, 6-hydroxy-5-
hydroperoxy thymine and tentatively 5-hydroxy-6-hydroperoxy thymine.
These together with thymine loss, were determined quantitatively
under a variety of conditions....
The formation of cytosine hydroperoxide was detected in
aqueous cytosine solutions irradiated with Co-60 γ-rays at pH 2.
The nucleotide of cytosine, cytidylic acid, forms a hydroperoxide
which was detected in neutral solution. The stability of the hydroperoxides of cytosine, thymine, and their nucleotides was found to
be a function...
This thesis describes a study of the synthesis, stereochemistry,
and reactivity of cobalt(III) cysteinato (CyS) and related thiolato complexes.
The preparation of [Co(en)₂CyS]⁺ resulted in a product solution
containing a mixture of diastereomers in the ratio 2.3:1 (Δ:A). The isomers were separated by ion exchange chromatography, and
their absolute configurations...
Metal-organic polyhedra (MOPs) are discrete molecules comprised of a metal and interconnecting ligands. The resulting MOP structures are porous cages, and to date, they have shown great promise toward gas capture. Ammonia is a hazardous gas that is produced in enormous quantities for use in fertilizers. In this talk, I...
Water is an absolute necessity for life as we know it. It provides a useful medium in which chemical reactions take place that allowed for the development of single cellular organisms. When combined with the evolutionary accident that was pho- tosynthesis, water became not only a useful medium chemical reactions,...
My work has focused on investigating synthetic organic reactions using applied computational methods. Non-covalent interactions are critical to catalysis, mechanism, and stereoselectivity, with the most prominent interaction for isothioureas being the S···O contact between the catalyst sulfur atom and the oxygen of the acyl group. A comprehensive joint experimental and...
An emerging strategy to reducing food waste is converting food processing byproducts to nutritious and inexpensive food ingredients. A relevant food processing waste stream is brewers’ spent grain (BSG), the primary byproduct of beer production. BSG is a promising candidate as a food ingredient because of its high protein and...
_____________________________________________________________________
Daniel Smith, Committee Member, representing Department of Food Science & Technology
Phospholipids and cerebrosides of the normal chick sciatic
nerve were extracted by Folch procedures and separated with silica
gel thin-layer chromatography using various chloroform-methanol
solvents. The subsequent chemical assays were expressed as a function
of the developmental stages of the chick from 15 days of incubation
to 7 days after...
Three distinct methods to achieve the stereoselective synthesis of carbon-carbon bonds were investigated, encompassing: (i) the formation of axially chiral biaryl molecules by enantioselective Suzuki cross-coupling, (ii) the synthesis of α-phenylalkylboronic esters by enantioselective chain extension, and (iii) the stereospecific synthesis of alkenes by eliminative cross-coupling of enantioenriched sp³-hybridized carbenoids....
Xanthohumol [XN, (E)-6´-methoxy-3´-(3-methylbuten-2-yl)-2´,4´,4´´-trihydroxychalcone], the principal prenylated chalcone from hops, and its 2,3-dihydro- (DXN) and O6-desmethyl-2,3-dihydro- (DDXN) congeners, are of potential utility for the amelioration of metabolic syndrome; however, their complex bioactivity profiles cannot be properly studied and understood without access to appropriately produced synthetic materials.
In the first part of...
Halogenated Polycyclic Aromatic Hydrocarbons (X-PAHs) are ubiquitous contaminants that are thought to be generated by processes such as chemical industries and incomplete combustion, including waste incineration and electronic waste (e-waste) burning. X-PAHs are a concern for environmental and human health because they are toxic, mutagenic, and are expected to be...
An analytical technique has been developed for the determination of methylmercury compounds in environmental samples. The technique is based on a two-stage procedure. In the first stage, methylmercury compounds are isolated from the sample matrix as methylmercury chloride (MeRgCl) by distillation. The distillation procedure is based on a series of...
Aqueous hydroxo Hf nanoclusters enable studies to identify and codify steps in the deposition of Hf-based oxide thin films from solution precursors. HfOCl2 reacts with combinations of H2O2(aq), acids, and TMAH to produce polymetal species at high pH and low pH. X-ray scattering and spectroscopic methods reveal the nature of...
The rate of the C¹⁴0₂ release from glucose, specifically labeled
with C¹⁴ at 1, 2, 3+4, and positions, was used to study the relative
participation of pathways of glucose catabolism in red beet slices.
Evidence was obtained which indicated that in mature red beets glucose
was catabolized mainly via glycolysis-tricarboxylic...
Neptunium, with its rich redox chemistry, has a special position in the chemistry of actinides. With a decades-long history of development of aqueous separation methods for used nuclear fuel (UNF), management of neptunium remains an unresolved issue because of its not clearly defined redox speciation. Neptunium is present in two,...
The total synthesis of a highly potent cytotoxic marine natural product, phorboxazole A, is described. Both a palladium(II)-mediated and a palladium(II)-catalyzed intramolecular alkoxycarbonylation were used as key steps for the preparation of the two cis-2,6-disubstituted tetrahydropyran rings (C22-C26 and C11-C15) of phorboxazole A.
The synthesis used a convergent approach involving...
Complex organic transformations, such as the addition of pyrrole to ketene using planar chiral organocatalyst (*PPY), the four-component anhydride- Manniach reactions, and the site-selective desymmetrization of meso-1,2-diol, are remarkable synthetic reactions that provide high yield and high selectivity. However, the exact mechanism and origins of stereocontrol for theses synthetic organic...
In this report, three studies are presented that utilize computations to predict transformations, identities, and properties of environmental organic molecules. Each study shows how computations can lead to models of chemical behavior. The importance of this research is rooted in the need for understanding how human behavior and health intersect...
In this dissertation, a novel method for analyzing computed transition states (TS) for organic reactions is disclosed. It introduces the use of localization-delocalization matrices as parameters in a linear free energy relationship to determine the transition state interactions responsible for differences in energy between the major and minor TS in...
The stereocontrolled synthesis of the southern lactone 17 of
boromycin and of the northern segments of both boromycin and aplasmomycin
are described. The syntheses begin with enantioselective
epoxidation of 3-buten-2-ol (42) to provide the optically active
2(S),3(R) epoxy alcohol 43. The absolute configuration was confirmed
by preparing 43 from (-)-2,3-dihydroxybutyric...
Fluorescence has proven to be a robust and powerful method of analysis in numerous fields: forensics, pharmaceutics, geology, food science, and environmental sciences have all developed a large collection of fluorescence instruments and methods to overcome application-specific challenges. Biological applications saw the same development of a fluorescence toolkit with methods...
Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous contaminants formed from the incomplete combustion of organic material. These contaminants are of concern because of their widespread presence in the environment and toxic properties. In addition, PAHs encompass a class of diverse compounds with varying physicochemical properties and exist in the environment as...
Analytical chemistry is an area of chemistry primarily focused on the study and use of instruments for separation, identification, and quantification of an analyte of interest. Specifically, separation science within analytical chemistry often refers to the process of dividing mixtures into their small component parts based on differences in their...
Analytical techniques are utilized in a wide variety of applications. Traditionally, analytical measurements are achieved by trained personnel in a laboratory setting using expensive scientific instruments, which limits their applicability in resource-limited areas and point-of-care applications. Therefore, the concept of enabling these laboratory-based qualitative and quantitative assays in microfluidic device...
Capillary electrophoresis as a technique has many applications in a broad range of fields including forensics, environmental analysis, and biological analysis and as a separation method for samples such as oligonucleotides, peptides, proteins, and pharmaceuticals. The research conducted herein is for the antibiotic pharmaceutical ciprofloxacin HCl and three impurities. Sample...
3-Methyl-2,4-dioxabicyclo [3.3.1] nonane and 7-hydroxy-3-methyl-2, 4-dioxabicyclo [3.3.1] nonane were synthesized by the
method of Croxall, Glavis and Neher, although in low yields.
The structure of both compounds was proven by analytical
methods and analysis of their spectral properties.
Tentative configuration of C-3 in both compounds was
assigned on the assumption...
Polycyclic aromatic hydrocarbons (PAHs) are a group of environmental contaminants consisting of fused benzene rings. Parent-PAHs, methylated-PAHs (MPAHs), and PAHs with molecular weight of 302 a.m.u (MW302-PAHs) are considered as unsubstituted-PAHs. These unsubstituted-PAHs undergo transformation reactions resulting in the formation of PAH-transformation products (PAH-TPs), or substituted-PAHs, including nitrated-, oxygenated-, and...
In this thesis, I present a new method we developed to study low frequency (< 700 cm⁻¹) vibrational dynamics: Time-resolved third-harmonic generation (TRTHG) spectroscopy. Among a variety of vibrational spectroscopy techniques, TRTHG differentiates itself with robustness, versatility, and simplicity. In TRTHG experiment, that involves only two ultrashort laser pulses, the...
The photochemical reaction between O⁻ ions and F centers
was investigated. The activation energy was determined by the
Arrhenius law to be 0.10 + 0.04 eV for temperature below 180°K.
The diffusion of alpha centers towards the oxide ion was eliminated
as the rate limiting step and the low trapping...
Direct current conductivity measurements on KC1:O[superscript]= crystals
were used to determine an enthalpy of 0.42 ev for the dissociation for
anion-vacancy-oxide ion complex.
The entropy of dissociation was
found to be approximately -4x 10⁻⁴ev deg⁻¹. The intrinsic "activation" energy was found to be 1.91 ev as compared to 1.95 ev,...
Heats of immersion were obtained for four different organophilic
clay complexes in a series of normal alcohol-heptane mixtures
with alcohols of increasing chain length. The immersion calorimeter
employed was the Dewar type with a sensitivity of approximately
5 x 10⁻⁵°C.
Gel volumes were determined for two of the clay complexes...
While fluorochemicals have been detected all over the world and in wastewater
treatment plants, the effect of wastewater effluent on the receiving waters has not been
evaluated. In the first study, the mass flow of fluorochemicals emanating from
wastewater treatment plants along the Glatt River in Switzerland was evaluated. The...
A continuous amperometric monitor for aqueous sulfite solutions
has been developed employing the electro-oxidation of sulfur (IV)
in 0. 1 M sulfuric acid at a glassy carbon test electrode. The monitor
employs a hydrodynamic flow cell, in which the solution stream
enters the cell through an orifice impinging on the...
Ultraviolet spectroscopy and dispersive solubility parameters
correlated to the ratios of retention times have proven valuable in
classification of gas chromatography stationary phases by the donor-acceptor
properties. Iodine was directly dissolved into stationary
phases and the absorption frequency shift of complexes was correlated
with the carbon tetrachloride/chloroform retention ratio on...
The use of semi-volatile organic compounds (SOCs) as molecular markers to identify the contributions of regional and long-range atmospheric transport, as well as current and historic sources, and contaminant deposition in remote ecosystems of the Western U.S. was investigated. Trans-Pacific air masses influenced by Siberian biomass burning events had elevated...
The work presented here is focused on applying basic principles of solid-state chemistry to the study and development of new wide band-gap semiconductors and insulators for photovoltaic and electronic-device applications. Analysis of crystal structure, band structure, optical band gap, morphology and transport properties provides fundamental insight into materials performance as...
Reaction of 4, 6-dimethoxy-5-nitropyrimidine [I], with refluxing
pyridine, was discovered to yield the methylpyridinium salt of
1, 6-dihydr -4-hydroxy-1-methyl-5-nitro-6-oxopyrimidine [III]. Possible
use of I as a general N-methylating agent was explored. No
appreciable reaction occurred between I and refluxing excess n-butyl
alcohol. Similar reaction involving quinoline failed to yield an...
Trichloroethene (TCE) is the most frequently detected organic contaminant in groundwater, is classified as a probable human carcinogen, and exhibits toxicological effects on the human endocrine, immune, developmental, and reproductive systems. While significant research efforts have been devoted to the development of strategies for remediating TCE-contaminated groundwater, their advancement is...
The plant Senecio jacobaea (tansy ragwort) produces several macrocyclic pyrrolizidine alkaloids which cause irreversible liver cirrhosis. All of the pyrrolizidine alkaloids in Senecio jacobaea are macrocyclic diesters of the necine base retronecine, with the two most predominant being seneciphylline and jacobine. Unlike horses and cattle, sheep and goats are generally...
Linear alkylbenzenesulfonate (LAS) is the most widely used anionic surfactant in
commercial detergent formulations. The environmental fate of LAS is of interest because
of its disposal to wastewater treatment facilities and subsequent occurrence as a
micropollutant in surface waters and groundwater. While LAS fate in wastewater
treatment systems and surface...
The dielectric relaxation of V₂ 0₅ was investigated using the method of Davidson and Cole. By means of an Argand diagram, deviation from an exact Debye dielectric was established. This was done with the parameter β. For a Debye dielectric β= 1. The largest value of β for V₂O₅ was...
A new experimental apparatus was built at Oregon State University to perform high resolution stimulated Raman spectroscopy in a pulsed molecular jet at state densities of the order of 10¹¹ cm⁻³. The technique uses a stimulated Raman step to first populate a vibrational/rotational level and then a resonantly enhanced multiphoton...
A practical and versatile instrument has been developed both to
optimize the chemistry of bio- and chemiluminescence reactions and to
measure ultra-trace quantities of associated analytes. The instrument
consists of a pneumatic flow injection system linked to a detection cell and a
signal processing and readout system. The disk-like cell...
The transport and deposition of airborne contaminants, including semivolatile
organic compounds (SOCs), to high elevation ecosystems is
recognized as a potential threat to these ecosystems. The objectives of
this research were to develop an analytical method to measure a wide
range of SOCs in high elevation lake sediment and to...
Chlorinated aliphatic hydrocarbons (CAHs) such as vinyl chloride (VC) and 1,-2 dichioroethane (DCA), are wide-spread groundwater pollutants found at many contaminated field sites around the world. Quantitative tools are needed to determine the in situ rates of VC and DCA transformation to ethene in contaminated groundwater. The objective of this...
A method of calculating the normal vibrations of polymer molecules
is presented in detail. The method is based on that used by
Schachtschneider and Snyder in their analysis of polypropylene but
has not heretofore been published. The factoring of the infinite matrix
and reduction to the coordinates of the unit...
The 3-cyclohexenyl carbinyl carbene species was formed by the
thermal decomposition of the p-toluenesulfonylhydrazone sodium
salt and by oxidation of the hydrazone. Several oxidizing agents
were studied. The products were investigated under aprotic and
protic conditions and at various temperatures. The diazocompound
was formed as an intermediate and found to...
Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous contaminants and are mostly products of the incomplete combustion of organic material. PAHs are often found in environmental samples as a complex mixture of isomers. In addition, the same sources that produce complex PAH mixtures also produce other poorly characterized mixtures of organic compounds,...
The infrared spectra of the metaborate monomer and trimer
ions in NaC1, KC1, and KBr were studied. These spectra contain
bands due to the trimer in solid solution, in a second phase of the appropriate
potassium or sodium salt, and perhaps on adjacent lattice
sites. Furthermore, complex equilibria exist between...
The primary focus of this work is on examining structure-property relationships of interest for high-power nonlinear optical and laser crystals. An intuitive and simply illustrated method for assessing the nonlinear optical potential of structurally characterized noncentrosymmetric materials is introduced. This method is applied to materials including common quartz and tourmaline...
An automatic, continuous analyzer has been developed which
is suitable for estimating the level of spent sulfite liquors (SSL) in
laboratory samples. The analyzer makes use of a version of the
Pearl-Benson, or nitroso method, and, in its present form, is
useful for samples whose actual SSL solids concentrations are...
Ambient high-volume (hi-vol) air samples were collected between March 15th and May 30th 2002, at Cheeka Peak Observatory (CPO), located on the tip of the Olympic Peninsula, Washington State. This sampling campaign was in conjunction with the 2002 Inter-Continental Transport and Chemical Transformation (ITCT 2K2) Campaign and the Photochemical Ozone...
Small molecule drugs have been instrumental in our fight against diseases, beginning when some of the earliest ancient cultures used plant remedies to treat illnesses. More recently, the skill of isolating and characterizing the active ingredients within bioactive plants and microbial extracts has led to the isolation and design of...
Aqueous film forming foams (AFFFs) are proprietary mixtures containing hydrocarbon surfactants and per-and polyfluoroalkyl substances (PFASs) that are used to extinguish hydrocarbon-based fuel fires. There is limited information on hydrocarbon surfactants in AFFFs and AFFF-contaminated groundwater even though they are more abundant (5-10% w/w) than PFASs (0.9-1.5% w /w) in...
Chemistry of preparing dense film from solution deposition is explored with several cases in this thesis. Surface dense structure, conversion at melting point, and ion exchange in aqueous solution are the main topics covered here for the thin films of aluminum oxide phosphate and tin dioxide. Thin film density, optical...
Preparation of a cytochrome c-cytochrome oxidase complex
was achieved, using crystalline beef cytochrome c and purified
cytochrome oxidase from beef heart muscle, or from the
Keilin-Hartree preparation. Succinate oxidase was reconstituted
with the complex.
A mixture of cytochrome oxidase, solubilized with nonionic
detergent, and excess cytochrome c was exposed to...
Studies toward the total synthesis of a highly potent cytotoxic marine natural product, phorboxazole A, were conducted and resulted in a route to an advanced intermediate, C4-C32, for this purpose. A key feature of our approach is the stereoselective synthesis of two cis-2,6-disubstituted tetrahydropyrans present in the macrolide portion of...
Toxoflavin, a toxic secondary metabolite produced by a variety of bacteria, has been implicated as a causative agent in food poisoning and a virulence factor in phytopathogenic bacteria. This toxin is produced by the tox operon in Burkholderia glumae, in which the encoded protein, ToxD, was previously characterized as essential...
The incorporation of europium and dysprosium in potassium
chloride crystals was investigated. The crystals were prepared by
the Kyropoulos method from melts containing the rare-earth chlorides.
The concentration of these rare-earth ions in the crystals was determined
by neutron-activation analysis. The distribution coefficient of
europium and dysprosium between the molten...
Many D2d-symmetric 2,2',6,6'-tetrasubstituted biphenyls are
readily prepared via net oxidative dimerization of appropriate
1,3-disubstituted benzenes. Conversion of such proprochiral
compounds to useful C2-symmetric chiral biphenyls requires
formal replacement of two substituents on opposing aryl ring
units with alternate groups. This under exploited
desymmetrization tactic has been demonstrated for the
generation...
Tacrolimus is an immunosuppressant drug approved by the FDA for the prevention of organ transplant rejection. However, the use of this drug is hindered by its narrow therapeutic window and extreme insolubility in water. Due to these properties, the currently used tacrolimus preparations must be administered once or twice daily...
Many pesticides, polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers
(PBDEs), and polycyclic aromatic hydrocarbons are persistent, bio-accumulative, and
toxic. These semi-volatile organic compounds (SOCs) can undergo atmospheric
transport and deposition in cold, remote ecosystems. A better understanding of their
accumulation in the fish of these ecosystems is important to better predict...
Solid state luminescent sulfides are prepared as powders in order to elucidate the relationship between structure and light emission. While the sulfides studied in this dissertation are known phosphors, materials are investigated in a variety of new ways. Elementary properties and structures of MgS are reviewed, and preparation of MgS...
The production of C¹⁴O₂ metabolized from glucose labeled in
specific carbon atoms by homogenates of chick embryonic and adult
heart was compared by the radiorespirometric technique. Homogenates
of early (two to five days of incubation) embryo hearts were
found to utilize the phosphogluconate pathway of glucose catabolism
to a greater...
The electrochemistry of the lithium-potassium-sodium
carbonate-borate melt was explored by voltammetry and chrono-amperometry. In support of this, a controlled-potential polarograph
and associated hardware was constructed.
Several different types
of reference electrodes were tried before choosing a porcelain membrane electrode containing a silver wire immersed in a silver sulfate
melt.
The...
The techniques of coherent anti-Stokes Raman spectroscopy (CARS)
and inverse Raman spectroscopy (IRS) are used to examine carbon dioxide
aggregation in a supersonic jet expansion. To promote the formation of
small clusters, a BMW injector valve is modified to permit its use as a
pulsed nozzle at very cold temperatures....
In the United States, falls are the leading cause of fractures and accidental death in the elderly; 70% of these fractures are women. Hispanic women account for a large population in the US, however data on falls and fractures for these women is lacking. The purpose of this systematic review...
My work on computing complex catalyzed organic transformations reveals that only a few subtle chemical factors, e.g. non-classical hydrogen bonding, (hyper)conjugation and steric effects, common across different catalyst manifolds are critical for catalysis and selectivity. Rational manipulation and exploitation of these factors has led to improved catalyst designs, which has...
Although 4- and 5-diacetamidopyrimidines have been reported
in the literature within the past eleven years, it was not until 1965
that a 2-diacetamidopyrimidine was reported. The current investigation
was undertaken to determine whether other 2-diacetamidopyrimi-dines could be synthesized and what the effect of various nuclear substituents would be on the...
Solubility studies on the heavy metal sulfides in liquid hydrogen
sulfide at room temperature were carried out using the isopiestic
method. The results were compared with earlier work and with a
theoretical result based on Raoult's Law. A relative order for the
solubilities of sulfur and the sulfides of tin,...
The theory and ways of applying a new electroanalytical detectior
method were developed. The method, called galvanovoltammetry,
consists of the measurement of current from the bipolar electrode of
a three electrode cell which consists of a working electrode and a
counter electrode, between which a constant current is applied, and...
The variable length, six-electrode plasma source for atomic
emission spectroscopy described here is operated from three
compact, simple, and inexpensive direct current power supplies. The
vertical arcs formed between the three electrode pairs completely
entrain the sample and are typically operated at 40 V and 20 A.
Three concentric quartz...
PART I. The preparation of (-)-ibogamine (1) in fourteen steps from benzoquinone and in 10% overall yield is a powerful illustration of the value of the asymmetric Diels-Alder reaction as a starting point in a multistep synthesis. All four cycloadducts, 70, 77, 84 and 96, obtained with the (S)-BINOL-TiCl₂ complex...
The atmospheric transport of anthropogenic semivolatile organic compounds (SOCs) from Asian sources to the Western U.S. was investigated. In addition, the SOC extraction method was optimized. Hansen solubility parameter plots were used to aid in the pressurized liquid extraction (PLE) solvent selection of air sampling media in order to minimize...
Two approaches to the tricyclic core of the furanoeremophilane sesquiterpenoids are described. The first approach entails a projected Diels-Alder/retro Diels-Alder reaction of an acetylenic oxazole 64. Construction of the pivotal aldehyde 67 commenced from ketone 68. The acetyenic moiety was then introduced via a Felkin-Ahn addition of lithiopropyne to aldehyde...