Thermal decomposition of several di-p-toluenesulfonylhydrazones
was studied. It was found that the carbene decomposition
of tetramethyl-1,3-cyclobutanedione, di-p-toluenesulfonylhydrazone
gave two products resulting from
rearrangement. One was identified as 2,5-dimethyl-1,3,4-hexatriene. A tentative structure for the second was
proposed. During the course of the study, a more convenient
procedure for thermal decompositions was...
This thesis describes a Mossbauer effect and electron
paramagnetic resonance study of iron (III) tetraphenylporphyrinatobenzenethiolate
benzene thiol, an analog compound
for bacterial cytochrome P-450. The compound is unusual in
that it provides a model for the two ferric reaction states
of cytochrome P-450. The iron in the model compound exhibits...
A series of compounds, 7-8 and 20-25, were tested as competitive inhibitors of 2,5-dihydroxyacetanilide epoxidase I (DHAE I) and DHAE II. A Hammett plot was constructed for each enzyme to determine the effect of electron density on inhibition. DHAE I gave a linear, highly correlated plot (r²=0.91) that signifies the...
The 3-substituded indolic enamide moiety has been found in many marine compounds over the past 20 years. These indolic enamides exhibit various biological properties such as cytotoxic, anthelmintic, antimicrobial and HW-inhibitory activities. Among these indolic enamides, some are (E)-enamides, like coscinamide A and coscinamide B, others are (Z)-configuration in their...
New transparent p- and n-type semiconductors and luminescent materials have been prepared and characterized. Synthesis, structures, optical and electrical properties of new chalcogenide fluoride p-type transparent semiconductors MCuQF (M=Ba, Sr; Q=S, Se, Te) are described. Band-gap tuning and improvement in conductivity through p-type doping are demonstrated in the family. The...
In this report, two studies are presented that utilize computations to predict and elucidate the reaction mechanisms of two different copper catalyzed reactions. Each study provides insight into the various chemical transformations, as well as the how and why behind regioselectivity and isotopic selectivity. The importance of this research is...
In this dissertation, the structural properties, thermodynamics and defect behavior of amorphous metal oxides and polyoxometalates are studied. Amorphous metal oxides have many applications, most notably as a semiconducting material used as the active matrix of thin film transistors. Alas, the amorphous nature of these materials makes studying them rather...
The yields of 235 projectile-like and target-like fragments from the interaction of ¹³⁶Xe with a thick target of ²⁰⁸Pb at a center-of-mass energy, E[subscript cm], of 450 MeV were measured using γ-γ-γ coincidence data from Gammasphere and off-line γ-ray spectroscopy. The results give an expansive picture of the production cross...
The epoxide deoxygenation reaction is formally the reverse of theepoxidation reaction. Compared to epoxidation, which has reached its fullmaturity, epoxide deoxygenation has not been as intensively developed.Among the few deoxygenation reagents, a handful are catalytic in a metalcomplex, show high stereospecificity and operate under mild conditions. Acommon feature of all...
Studies toward the total syntheses of highly potent cytotoxic alkaloids
including the bromopyrrole alkaloids and indole alkaloids were conducted and are
described. Studies carried out in the course of this dissertation consist of five total syntheses of natural products that include bromopyrrole alkaloids nagelamide A, D and agelastatin D as...
In situ reduction of hydrido-tris-(3,5-dimethylpyrazolyl)borato(trioxo) rhenium(V) with triphenylphosphine or triethylphosphite leads to a reactive rhenium(V) species that catalytically deoxygenates epoxides at 75-105°C. The reaction is stereospecific, except for trans- and cis-butene oxide which formed minor amounts of the opposite isomer. A variety of different functional groups were tolerated and even...
In situ, reduction of Cp*ReO₃ by PPh₃ to form (Cp*ReO)₂(μ-O)₂ allows catalytic deoxygenation of epoxides, however, conproportionation between Reⱽ and Reⱽᴵᴵ species to form clusters of ((Cp*Re)₃(μ-O)₆}²⁺(ReO₄⁻)2 and new compound {(Cp*Re)₃(μ²-O)₃(μ³-O⁾³ReO₃}⁺(ReO₄⁻) leads to removal of rhenium from the catalytic cycle and loss of activity, The epoxide deoxygenation mediated by (Cp*ReO)₂(μ-O)₂...
The rhenium (V) complex Tp'ReO₂ (Tp' = hydrido-tris-(3,5-
dimethylpyrazolyl)borate), generated in situ from PPh₃ reduction of
Tp'Re0₃, reacts with small ring heterocycles such as epoxides and
episulf ides. The strained trans-cyclooctene ring provides an unusual
thermodynamic bias against direct atom transfer, but trans-cyclooctene
oxide still produces substantial amounts of trans-cyclooctene....
The rhenium dithiodiolate, Hydrido-tris-(3 ,5-dimethyl- 1 -pyrazol yl) borato(ethane- 1 ,2-dithiodiolato)(oxo)rheni um(V), and Hydrido-tris-(3 ,5-dimethyl- 1 -pyrazolyl)borato(phenylethanedithiodiolato)(oxo)rhenium(V), were synthesized by reductive cyclocondensation of alkane-1,2-dithiols with Tp'Re0₃ in a one pot fashion. The rhemium monothiodiolate, Hydrido-tris-(3 ,5-dimethyl- 1 -pyrazolyl) borato(ethane- 1 ,2-monothiodiolato)(oxo)rhenium(V), and Hydrido-tris-(3 ,5- dimethyl- 1 -pyrazolyl)borato(propanemonothiodiolato)(oxo)rhenium(V), were also synthesized...
This dissertation demonstrated that the electrical properties of complex oxide-based perovskite materials could be controlled through the careful modification of both material composition and structure. This was first shown through the modification of lead zirconate titanate (Pb(Zr0.52Ti0.48)O3, PZT) solid solutions with bismuth indate (BiInO3, BI) where the relative stability of...
An intramolecular variant of the modified-Julia olefination was demonstrated by the synthesis of α,β-unsaturated lactones in a mild and (Z)-selective fashion. The lynchpin reagent (benzothiazol-2-sulfonyl) acetic acid was synthesized in a straightforward fashion in 86% overall yield from commercially available 2-mercaptobenzothiazole via conversion to ethyl (benzothiazol-2-ylthio)acetate by base mediated alkylation...
The first part of this manuscript is about the total synthesis of the aspidosperma alkaloids leuconoxine, melodinine E and mersicarpine. Our synthetic strategy used a radical translocation-conjugate addition cascade to construct the core of the natural product. Specifically, a vinyl radical was generated from the homolysis of the C–I bond...
We report the use of MIL-120 as a water-stable and cost-effective metal-organic framework (MOF) for selectively capturing CO₂ from wet flue gas. Synthesized using inexpensive and environmentally benign reagents in water, MIL-120 possesses one-dimensional pores decorated with hydroxyl-bridged Al(III) ions and benzene rings with an interstitial spacing of 4.78 Å....
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,...
Feeding of [3-¹³C, 2-¹⁵N]arginine, 38a, unequivocally established that the β-
arginine moiety of blasticidin S, 1, was formed from α-arginine by an intramolecular
migration of the α-amino group to the β- position. Further feedings using chirally
deuteriated arginines 38e and 38f revealed that the aminomutase process occurred with
inversion of...
Tuberculosis (TB) is a pressing global health issue with approximately one third of the world’s population infected by this bacterium. As one of the most dangerous infectious diseases, it has killed approximately 1.7 million people of all ages around the world per year (World Health Organization, 2016). Currently, several drugs...
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....
This work investigates the relationship between the local structure and physical properties of a set of classical (MgTiO3, CaTiO3, SrTiO3, and BaTiO3) and complex ((1-x)Ba(Zr0.2Ti0.8)O3-x(Ba0.7Ca0.3)TiO3[BZT-BCT], Na0.5Bi0.5TiO3 [NBT]) perovskite electroceramics. The materials in this work were synthesized via standard solid state ceramic synthesis, the structure was investigated through a number of...
PART I. A deuterium exchange analysis of 2,5-dihydroxyacetanilide (5) in the absence and presence of DHAE II was performed to test the nucleophilicity of the substrate in the absence and presence of catalyst. In addition, inhibition studies using 1,4-dihydroxybenzene were performed to determine the role that the N-acetyl side chain...
Traditional approaches for the direct preparation of alkenes are unable to fully control either the stereochemical configuration of the carbon-carbon double bond or else the regiochemistry of the substituents surrounding it. The recently introduced concept of carbenoid eliminative cross-coupling (CEXC) offers a remedy to these deficiencies by providing for a...
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...
2,5-dihydroxyacetanilide epoxidase from Streptomyces LL-C10037 (DHAE I)
catalyzes the epoxidation of hydroquinone 4, to form epoxyquinone 7. DHAE I has been
purified to homogeneity, with an overall purification factor greater than 23,000. N-terminal
and internal amino acid sequences have been obtained from the purified enzyme so
that the epoxidase gene...
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...
The objectives of this study were to isolate 2, 4-diaminobutyric
acid and to attempt cyclizing the acid and its disulfonamide derivative.
The original synthetic method by Adamson was followed but a
modified isolation procedure for the acid was employed.
Following the synthesis, the acidic solution was passed through
Dowex-3 ion-exchange...
This dissertation presents a study of structure-property relationships within 3d/4d metal oxides containing precious metals through detailed structure refinements using high-resolution neutron and X-ray diffraction data along with exploration of the resultant properties.
Oxides of 4d or 5d transition metals tend to show new topological phases due to significant spin-orbit...
Since the use of N, N-diethylaniline hydrochloride in the chlorination
of uric acid with phosphoryl chloride seems to promote the
reaction, a study of the effect of other salts of nitrogenous bases in
the chlorination of uric acid was undertaken. When N, N-diethylaniline
hydrochloride was used in lieu of the...
The first area of investigation involves the electron transport
of sub-mitochondrial particles and their components. The second
area is the synthesis of ATP and other energy linked reactions and
components of the energy conservation and transfer apparatus.
Investigations on the nature of the tetramethyl-p-phenylenediamine
(TMPD) shunt indicated that tetrachlorohydroquinone (TCHQ)...
Transition metal oxides are an important class of materials for the wide variety optical, electrical, dielectric, magnetic, and thermal properties observed. Their unique structure-property relationships allow for property tuning and often provide insight into the fundamentals of chemistry. The work in this thesis was focused on the design, synthesis and...
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...
The discovery of new blue pigments is a field of great interest, as commercially available pigments present properties that make them undesirable such as poor sustainability, cost, and stability. By researching solid solutions with the melilite structure, we discovered a new solid solution Sr2Zn1-xNixGe2O7, with 0.1 ≤ x ≤ 0.6,...
Nanoparticles are a hugely diverse category of material that have a wide variety of biomedical applications, and developing tools for biological research with high cellular uptake is critical to their effective application. However, rarely is attention paid to the exact mechanism by which this is occurring, with most studies focusing...
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...
The structural architecture present in marine toxin azaspiracid - 20 stereocenters, 9 rings, 3 separated spirocenters - has attracted considerable synthetic attention. Our efforts toward the synthesis of azaspiracid have led to the completion of both C₁-C₂₆ northern and C₂₇-C₄₀ southern halves. Herein, the
synthesis of southern FGHI ring system...
Phosphate and peroxide stabilize new oxo-hydroxo niobium clusters in water at low pH. The clusters open a new chapter in aqueous niobium chemistry under acidic conditions. The clusters also produce atomically smooth, amorphous niobium oxide phosphate (NbPOx) thin films. Reaction pathways from cluster solutions to amorphous niobium oxide phosphate solids...
The work presented here is the culmination of efforts in describing complex chemical systems with statistical methods, thereby providing relatively simple quantitative models and easily comprehensible qualitative insights. The following investigations have various goals, such as development of new methods, fundamental understanding, molecular control of chemical species, and advancement of...
The results of the research presented in this work are related to synthesis and investigations of novel color inorganic pigments having various structures and shades. Inorganic pigments play a major role in contemporary life. They are used in paints, rubber, plastic, cosmetics etc. Searching for new, stable, environmentally benign and...
In this dissertation, the process of computational modeling of amorphous oxide materials is studied. Amorphous oxides have random atomic arrangements with no long-range structural order which makes it difficult to study structure-property relationships. Despite the difficulties, amorphous oxides have great uses as semiconductors and dielectrics in thin-film transistors. The ability...
The central purpose of this dissertation was to explore and expand the use of
an uniform electric field for orientation and for subsequent spectroscopic investigation of asymmetric polar molecules in the gas phase. The systems of study were nitrobenzene (NB) and the nitrotoluene (NT) isomers. We were able to quantitatively...
Widespread installation of renewable energy sources, such as wind and solar, has been delayed by the lack of suitable stationary energy storage solutions. Current large-scale technologies, such as pumped hydro and compressed air, are geographically restricted. This is where electrochemical energy storage - batteries or hybrid capacitors can play a...
As scientists, we have an affinity for order: repeating crystal structures, Euclidean space, continuous functions… Even concepts such as defects are discussed in the context of distracting from order. Things are most logical and best described in straightforward, taxonomical fashion. But what happens when the very application desired is dependent...
Benzylsuccinate (BSA), methylbenzylsuccinate (methylBSA), and ethylbenzylsuccinate (ethylBSA) are unambiguous anaerobic biotransformation products from toluene, xylenes, and ethylbenzene decay, respectively, and may be used to indicate intrinsic bioremediation is occurring at hydrocarbon-contaminated sites. In order to improve upon current methods that detect and quantify anaerobic hydrocarbon metabolites in field samples, solid-phase-extraction...
The CARS apparatus at OSU was modified to permit studies in the 0-500 cm⁻¹ spectral region. The new low frequency capabilities were then used to study molecular clusters formed in free expansion jets of carbon dioxide. A strong cluster band was observed at 73 cm⁻¹, with a weaker shoulder at...
In this dissertation, the primary objective is to discover more sustainable electrode materials and study new reaction mechanisms using aqueous electrolytes. The first study conducted reveals a reversible conversion reaction from copper to Cu2CO3(OH)2. The reaction mechanism uses OH- and CO32- as charge carriers at the cathode. The results open...
Theoretical studies and experimental results are presented for the rotational motion of molecule's in crystalline solids. The group theory is solved for molecules of any symmetry matrix isolated at a site in a crystal field of any symmetry. As the potential terrier to rotation of the molecule relative to the...
The effect of the conjugation with cyclopropyl rings
on the activation parameters for the formation of
carbenes from the corresponding diazo compounds was
investigated using diisopropylcarbene (46), cyclopropyl-isopropylcarbene
(47), and dicyclopropylcarbene (48).
Each of these three carbenes was generated by the
thermolysis of the parent benzenesulfonylhydrazone
potassium salts using DMSO...
One post-transcriptional mechanism that regulates the progression of cancer and other diseases involves small 22-23 nucleotide sequences called microRNA (miR). Early detection of small changes in concentration of these biomarkers holds potential to diagnose diseases at their earliest stages. Use of current nucleic-acid based biosensors, like molecular beacons, for in...
The purpose of this research was to compare four different media that were used to monitor SOC atmospheric concentrations in remote ecosystems. The accumulation of semi-volatile organic compounds, including pesticides, polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs), was investigated in lichen, 2-year old conifer needles, resin-based passive air sampling...
The DNA-binding domains of E. coli uracil-DNA glycosylase (Ung) and human replication protein A (hRPA) were studied using a general protocol developed in our laboratory for probing protein-DNA interactions. The procedure involves purification and mass spectrometric analysis of the nucleopeptide-products of a tryptically digested UV-crosslinked protein-nucleic acid complex. In the...
The rate of removal of benzene, toluene, ethylbenzene and the xylene isomers (BTEX) from contaminated groundwater is needed to design remediation processes. Benzylsuccinic acid (BSA) and methyl-benzylsuccinic acid (methyl BSA) are unambiguous metabolites of anaerobic BTEX biodegradation. An analytical method for quantitative determination of BSA in groundwater samples was developed....
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...
Neurofilament proteins are intermediate filaments found in the neuronal cytoskeleton. Phosphorylation of these proteins is considered important for the assembly and stability of the filaments. Accurate molecular weights have been difficult to measure, largely because the high degree of phosphorylation results in M[subscript r]'S that are significantly greater than dictated...
The electronegativities of -SF₅, -CF₃SO₂, and -SO₂F have been measured with gas phase X-ray photoelectron spectroscopy. Of these three groups previously measured values were found only for -SF₅. The electronegativities of -Cl, -Br, -CF₃, and -CF₃, were concurrently measured to determine how the findings of this research compare with other...
Iodine-129 is a key risk driver at sites where nuclear materials have been fabricated or processed, and it is a predominant isotope of concern in long-term waste storage strategies. I-129 exists primarily as iodate in the subsurface at the Hanford Site in south-central Washington State. Between 15 and 40% of...
Integration methods for enzymatic reactions were applied to
transducer response vs. time curves which exhibit maxima, minima or
inflections. The difference between the integral of the time
dependent response and the initial response, often zero, is related
to the initial enzyme activity or substrate concentration. Fluorescence response curves which exhibit...
The observed and calculated structural parameters of three systems
of phosphatidylcholine bilayers in fully-hydrated multilamellar
vesicles (MLVs) were determined using x-ray diffraction techniques.
The analysis used the x-ray reflections from the low-, intermediateand
wide-angle regions of the diffraction patterns in the subgel, gel,
rippled and fluid phases to determine the...