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 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...
An important aspect in device technology is the
processing of GaAs to produce highly-resolved etch
patterns on the substrate. This is done typically on the
GaAs(100) surface. Recently, a number of methods, all
using chlorinated vapor reactants, have been applied to
fabrication of GaAs devices. In spite of these
technological...
Dearomatization reactions exist broadly in biosynthesis and chemical synthesis. The highly functionalized atoms of arenes can be masked by it aromaticity, and upon dearomatization, those reactive atoms can be readily applied to bond formation and further manipulation. The total synthesis of (–)-cephalotaxine and (–)- homoharringtonine is described via an oxidative...
Substituted phenols are important substructures for pharmaceuticals, agrochemicals, natural products and biological probe molecules. The properties of phenolic molecules are substantially influenced by the substitution patterns of the phenolic ring. The chemical synthesis of phenols with various substitution patterns is an enduring challenge and multiple strategies have emerged. However, some...
Organic compounds which contain one or more nitrogen atoms are especially important as they are disproportionately represented among biologically active molecules. As a result, significant effort has been focused on the development of methods for the synthesis of nitrogenous molecules. We identified the aminal as an under-explored functional group. Despite...
Novel ternary graphite intercalation compounds (GICs) of alkali metal cations
and a wide variety of amines have been synthesized by one-pot chemical syntheses.
Alkali metals studied includes Li, Na and K. The families of amines employed are nalkylamines,
branched alkylamines, and different structural isomers of diamines and
polyamines. Intragallery structures...
Aminal radical intermediates were generated by the method of radical translocation and reacted in C-C bond forming reactions with electronically deficient alkenes (Schiedler et al. Org. Lett. 2012, 14, 6092). Aminal radical intermediates can participate in inter- and intra-molecular reactions using both Bu3SnH and (TMS)₃SiH as hydride donors. Carbon–carbon bonds...
Pharmaceuticals, molecular catalysts, and secondary metabolites often contain nitrogen. The problems faced synthesizing compounds which contain nitrogen was because of the Lewis base reactivity of nitrogen lone pairs, and the acidic protons of some nitrogenous functional groups. We developed two methods for the synthesis of nitrogeous compounds. Additionally, we successfully...
Detection technique that proposed utilizing electrochemically controlled, reversible ion extraction into polymeric membrane in an alternating galvanostatic/ potentiostatic mode was introduced. This method is studied in detail to comprehend the advantages of the novel sensor (pulstrode) compared to the potentiometric ion selective electrode (ISE), studies included possible applications and limitations....
Amorphous metal thin films lack the grain boundaries and dislocations present in
crystalline metal films. As a result, amorphous metal films can be more mechanically robust, atomically smooth, and more resistant to chemical attack than crystalline metals. However, amorphous metals are meta-stable and subject to crystallization upon heating, thus limiting...
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...
Two distinct strategies were explored for the enantioselective synthesis of α-heteroatom substituted alkyl boronic esters by stereoselective reagent-controlled homologation using transient chiral carbenoid reagents CHYMX (Y = heteroatom, X = nucleofuge, M = electrofuge). In the first case, a stereospecific reagent-controlled homologation (sStReCH) approach to α-alkoxyalkylboronates using α-metalated S,O- and...
Lycopodium alkaloids have shown widespread and noteworthy biological activity, consisting of over 250 known natural products. Moreover, their structural complexity and diversity have attracted considerable attention from numerous laboratories including our own. Recently, we have developed a unified approach that would provides access to numerous, previously unprepared C₁₀-functionalized lycopodium alkaloids....
The development of microfluidic devices for heavy metal extraction is presented in this dissertation. Various research areas, covering subjects from photochromic compound syntheses to microchip fabrication techniques are explored to develop microfluidic devices capable of extracting heavy metal ions from drinking water. Through integration of the beneficial characteristics of both...
The general emphasis of this work has been synthesis, characterization, and applications of n- and p-type inorganic oxide thin films that are deposited from solutions. In particular, a study of n-type transparent semiconductor films of tin (IV) oxide and zinc-doped tin (IV) oxide has been performed by spin coating. Solution...
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...
A comparative study was made on the effect of urea denaturation
of bovine serum albumin (BSA), polyglycyl BSA and poly-L-phenylalanyl
BSA. The denaturation process was followed by ultraviolet
spectrophotometry and optical rotation.
A blue shift in the absorption maximum at 278 mμ was observed
in urea denatured proteins, In 7M...
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...
Part 1
The concentration of seventeen elements in two species of fungus
which cause wheat bunt disease, Tilletia caries (DC.)Tul. (TS) and
Tilletia controversa Kiihn (DS), were determined by instrumental neutron
activation analysis in 37 TS spore samples, and 31 DS spore samples.
Aluminum was chosen as a soil contamination...
Polypeptidyl derivatives of bovine pancreatic ribonuclease
(RNase) containing two or three tyrosine chains
with an average of two to three residues per chain have
been prepared. The effects of various perturbants such as
neutral salts, ethanol, urea and guanidine hydrochloride
on the thermal transition of the derivatives have been
studied....
The 105,000 x g supernatant fluid (S[subscript HS]) from extracts of pea seedlings
(Pisum sativum, var. Alaska) etiolated for 60 hours yielded a
very potent adenosine triphosphatase activity. This activity was designated
as an apyrase when the reaction stoichiometry indicated that
adenosine triphosphate (ATP) was hydrolyzed to adenosine monophosphate
(AMP)...
Novel synthetic strategies are developed to prepare new intercalation compounds and nanocomposites with several layered hosts (NiPS₃, Na-montmorillonite, MoS₂ and MoO₃). In these products, alkali metals are ionic intercalates and linear polymers, dendrimers or amines act as co-intercalates. In addition to new synthetic approaches, new structures are identified and characterized....
A method was developed to quantify organochlorine pesticides in whale scat. This method would ideally replace analysis of pesticides in blood and tissue samples, which are difficult to acquire. Scat samples were collected from one stranded gray whale and three live whales. The samples were extracted with pressurized liquid extraction,...
Novel graphite intercalation compounds (GICs) and associated chemistry have been explored, specifically: (1) containing alkyl- substituted imidazolium cations; (2) a series containing alkaline earth metal (Mg, Ca, Sr, Ba) cations with ethylenediamine (en) co-intercalates; (3) showing reversible intragallery M-M bonding and (4) via electrochemical intercalation of Mg cations with potential...
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...
Recently researchers have discovered that groups of small non-coding RNAs (ncRNAs) play regulatory roles in gene expression and participate in various biological processes. For example, pathogenesis of many diseases, cell cycle regulation, and signaling pathways. Intracellular and live cell imaging of small ncRNA groups will reveal their relative expression levels...
Inorganic structures play an important role in materials due to their versatility and diversity. A complete understanding of the structure of a material is vital to enhance the creation of new materials that fill voids in research. The rational design of these compounds is driven by the exploitation of structure-property...
Novel donor-typed ternary graphite intercalation compounds (GICs) are synthesized and characterized containing (1) pyrrolidinium cations with DMSO co-intercalates; (2) alkali metal cations with crown ether co-intercalates; and (3) alkali metal cations with polyethylene glycol co-intercalates. Structural and compositional data are obtained for the stable products. A new ether-amine co-intercalate exchange...
The melt intercalation of poly(ethylene oxide) (PEO) between layers of MoO₃ and MPS3 (M=Mn,Cd) is obtained by heating the ground mixture and LiₓMoO₃, KₓMn₁-ₓ/₂PS₃, or KCd₁-ₓ/₂PS₃. The products are characterized by powder X-ray diffraction (XRD). Below the melting temperature of PEO (66 °C), intercalation rates and yields are low. By...
Novel donor-type graphite intercalation compounds (GICs) containing tetra-n-alkylammonium (TAA) cations have been synthesized by using both ion-exchange and electrochemical methods. Structural and compositional data of the resulting TAA-GICs are investigated by using powder X-ray diffraction (PXRD), one-dimensional electron density calculations, thermogravimetric and elemental analyses, and capillary zone electrophoresis (CZE). A...
New synthetic strategies have been investigated for nano-dimensioned
graphite particles or even isolated graphene sheets. One approach is to prepare
graphite intercalation compounds (GICs) with low layer charge density and
appropriate gallery height, followed by the colloidal dispersion or exfoliation of the
resulting GICs. A series of anions has been...
Tethering fluorophores on metal nanoparticles for metal enhanced fluorescence (MEF) has attracted a lot of attention from scientists interested in fluorescence based approaches. MEF has many benefits in fluorescence related techniques, because the analytical signal increases and enables potentially lower detection limits or better sensitivity. Many types of nanoparticles have...
New chemical synthesis strategies have been investigated for the preparation of acceptor-type graphite intercalation compounds (GIC's) with fluoroanions in order to obtain new materials and to develop a better understanding of the synthetic approaches and properties of the products. New GIC's containing borate chelate anion such as bis(oxalato)borate, CxB[OC(O)C(O)O]₂•δF, are...
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...
Polycyclic aromatic hydrocarbons (PAHs) are environmental contaminants produced mainly from the incomplete combustion and pyrolysis of organic matter. PAHs are among the major contaminants at over 800 Superfund sites, nationwide. Thermal remediation is used as a method to remediate soils contaminated with PAHs through the use of heat to mobilize...
Investigating the structure-property relationships of solid state materials can help improve many of the materials we use each day in life. It can also lead to the discovery of materials with interesting and unforeseen properties. In this work the structure property relationships of newly discovered layered oxypnictide phases are presented...
Gold nanostars are a relative newcomer to the nanoparticle scene, and their unique properties make them very desirable for spectroscopic applications. These nanoparticles, with their sharp tips, create electric field enhancements that interact with light in an advantageous way. This Thesis outlines our in-depth study of gold nanostar synthesis, the...
Aromatic heterocycles are core structural motifs in natural products, pharmaceuticals and biological polymers. Indoles, in particular, represent a significant subclass of aromatic heterocycles, both in terms of sheer numbers, but also in biological and pharmaceutical relevance. As such, new methodologies for the synthesis of indoles represent an important and continually...
Ambifunctional axially chiral 2,2',6,6'-tetrasubstituted biphenyls containing nucleophilic (or basic) functional groups juxtaposed with hydrogen-bond donors were synthesized and their properties studied. Applications for the prepared biaryls as potential organocatalysts for enantioselective carbon-carbon bond forming reactions were examined. Processes investigated included: aldol, Michael, nitroaldol (Henry), and Baylis-Hillman reactions.
The novel amidoamine...
In Part I, (4S,5R)-4,5-dimethyl-4-phenylcyclohex-2-enone (19a) was prepared in 73% yield with high enantio- and diastereo-selectivity (er > 98:2, dr > 20:1) on a multigram scale by a Yamada-Otani condensation between (E)-pent-3-en-2-one and 2-phenylpropanal catalyzed by a sulfonimide derivative of (S)-proline (18, HuaCat®). Synthetically useful transformations of the cyclohexenone product 19a...
Lithium serves an unparalleled role for high energy-density storage applications and is vital for the continued advancement of the world economy. However, global supply is heavily reliant on lithium deposits situated in select locations, creating unpredictability in the price and concerns for the sustained production of the resource. Additionally, future...
In spite of their importance in many systems, liquid surfaces have been
explored at the microscopic level to a much lesser extent than solids. Most surface
analysis must take place in vacuum, a major drawback for liquids. The technique of
time-of-flight scattering and recoil spectrometry (TOF-SARS) has been applied to...
Polybenzimidazoles were synthesized from 3, 3', 4, 4'-tetraminobiphenyl
(diaminobenzidine, or DAB) with orthoesters, carboxylic acid derivatives (an ester and
an acid) and with m-benzenedialdehyde. The products were of low molecular weight,
as evidenced by low inherent viscosity, except in the case of the dialdehyde plus DAB.
The product of that...
This work investigates the effect of cation substitution on the properties of the lead-free, solid solution (Na₀.₅Bi₀.₅)TiO₃-BaTiO₃ (NBT-BT). Substitution into NBT-BT increases disorder and increases the relaxor ferroelectric properties. These relaxor ferroelectric materials show large piezoelectric strains that can be utilized in actuator applications. Ceramic samples were prepared using standard...
We have developed a compact micro total analysis system (μTAS) to serve as a platform for in-situ spectrophotometric water quality monitoring. Individual fluidic, optical, and electrical components were designed, developed, and characterized. These components were combined in both an integrated (single lithographic “chip-based” platform) and a modular manner. The microfluidic...
Enantioenriched sp³-hybridized carbenoid reagents CR1R2MX (X = nucleofuge, M = electrofuge) of different types were investigated for the synthesis of polysubstituted alkyl chains by iterative stereospecific reagent-controlled homologation (StReCH) and for the stereospecific connective synthesis of alkenes by eliminative cross-coupling.
In the first part, putative enantioenriched α-chloroalkyllithiums (CHRLiCl) were employed...
The stereospecific reagent-controlled homologation (StReCH) of boronic esters with putative lithiooxiranes generated in situ from appropriate precursors via sulfoxide-lithium exchange, tin-lithium exchange, and direct lithiation is described with an emphasis on the first lithiation technique which allows for the regio- and stereo-specific generation of all types of lithiooxirane isomer. Transient...
Chalaniline A, an unusual xanthone-like aminofulvene with modest cytotoxicity, and chalaniline B [1-anilino-2,8-dihydroxy-3-(hydroxymethyl)xanthone], an antibacterial aminoxanthone, were previously isolated by Loesgen and coworkers from vorinostat-treated Chalara sp. 6661. Of note, the anilino moiety found within both chalaniline structures originates from biotransformation of the HDAC inhibitor vorinostat (SAHA, suberanilohydroxamic acid) by...
A heat stable derivative of bovine serum albumin containing
300 residues of glycine added to 30 sites on the surface of the protein
has been prepared. This derivative may be heated to 100° C for
prolonged periods of time without aggregation. By comparison,
native BSA aggregates at 62° C under...
Several types of solid-state inorganic materials are prepared and characterized. By using the SILAR (Successive Ionic Layer Adsorption and Reaction) deposition method in conjunction with hydrothermal dehydration both low-temperature deposition and crystallization of oxide thin films are achieved. Various aspects of new transparent p-type materials are studied by examining both...
Azaspiracid-1, a novel marine toxin that contains 9 rings and 20 stereogenic centers, has drawn considerable attention from synthetic groups worldwide due to its structural complexity, which includes a unique trioxabisspiroketal fused to a tetrahydrofuran ring (ABCD rings), a piperidine-tetrahydrofuran spiroaminal system fused to a 2,9-dioxabicyclo[3.3.1]nonane system (FGHI rings), a...
Part I of this dissertation includes the chronological synthetic background of mandelalide A as well as the synthesis of the C1-C14 glycosylated southern subunit of mandelalide. A key aspect of the synthesis includes a novel silver-catalyzed cyclization (AgCC) of a propargylic benzoate to construct the substituted cis-pyran ring system present...
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...
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...
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 research emphasized fundamental physical and electrochemical
studies of systems based on the room temperature fused salt, triethyl-ammonium
dichlorocuprate(I). Such systems, which must be maintained
under a protective atmosphere, were also used in some preliminary
battery studies.
Spectra of dark green solutions of copper (II) chloride in
triethylammonium dichlorocuprate(I) obey...
The synthesis of axially chiral polyfunctional derivatives of 8,8'-biquinolyl was explored and the catalytic action of appropriate derivative types investigated in three separate processes: (1) the silylcyanation of carbonyl groups and imines, (2) alkylation of a glycine Schiff-base via phase transfer-catalysis, and (3) direct amide bond formation from simple amines...
The bimolecular reaction of two carbenoid species resulting in the formation of a carbon-carbon double bond (pi-system), referred to herein as carbenoid eliminative cross-coupling (CEXC), involves a series of three fundamental steps: (i) ate-complex formation (transmetalation), (ii) 1,2-metalate rearrangement, and (iii) beta-elimination. All three steps are stereospecific and so the...
The stereospecific reagent-controlled homologation (StReCH) of boronic esters with enantioenriched carbenoid species generated in situ by the addition of organolithium initiators to stereodefined α-chloroalkyl aryl sulfoxides was previously reported. The reaction of an organolithium with an α-chloroalkyl aryl sulfoxide ostensibly generates an α-chloroalkyllithium via sulfoxide-lithium exchange; however, the true nature...
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...
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...
Acetylimidazole was used to acetylate the tyrosyl residues
of insulin. The kinetics of acetylation were studied by termination of
the reaction at several time intervals, isolation of acetylated insulin
and determination of 0-acetyltyrosyl groups by deacetylation with
hydroxylamine. The deacetylation was also studied kinetically by
means of the absorbancy change...
The interactions of a model synthetic liquid fuel reactant (furan) with a model
hydrodeoxygenation catalyst (clean and sulfided single crystal molybdenum)
were investigated using the following UHV tools: Auger electron spectroscopy
(AES), low energy electron diffraction (LEED), and temperature programed
reaction spectroscopy (TPRS). In addition to furan, the reactions of...
In previous work (Blakemore et al. Org. Lett. 2005, 7, 4721; Heterocycles 2006, 70, 609), successful elaborations of the lupine alkaloids (±)-α-isosparteine (dl-2) and (±)-β-isosparteine (dl-3) were realized from a common tetraoxobispidine precursor, 3,7-diallyl -2,4,6,8-tetraoxo-3,7-diazabicyclo[3.3.1]nonane (93). Herein, the tetraoxobispidine approach to lupine alkaloids was extended to a total synthesis of...
In order to examine some possible tyrosyl interactions, poly-tyrosyl lysozyme and poly-O-methyltyrosyl lysozyme were prepared and their solubilities were compared. Both derivatives exhibited
similar pH dependent solubilities, showing a minimum solubility at
about pH 8. Their solubilities varied with temperature, having a
positive enthalpy of solution. The effect of a...
Levels of activity of glucose-6-phosphate- , 6-phosphogluconate- , and isocitric- dehydrogenase were measured in the
soluble and particulate fractions of heart, brain and liver at
several ages throughout the development of the chick embryo.
Compared to isocitric dehydrogenase, levels of glucosesphosphate-
, and 6-phosphogluconate- dehydrogenase are generally
low. This suggests...
Two perovskite materials (Bi0.5(A)0.5)(Sc0.5Nb0.5)O3, where A = K+ and Na+ were synthesized phase pure for the first time. Their structures were determined by indexing synchrotron X-ray diffraction data and subsequent combined Rietveld refinement on neutron and synchrotron X-ray diffraction data revealing significant disorder on the A-sites of these materials. A...
Polybenzimidazoles were synthesized from 3,3'-diaminobenzidine (DAB) and dicarboxylic acids. The polymerizations using the dicarboxylic acid monomers were carried out in polyphosphoric acid (PPA) and phosphorus pentoxide/methansulfonic acid (PPMA) which acted as the solvent and condensing agent. The resulting polybenzimidazoles had inherent viscosities in the range of 0.12 to 0.84 dL/g....
Isocitrate-NADP oxidoreductase activity in mitochondrial and
soluble fractions was determined for hearts, livers and brains of
chick embryos at various stages of development. One-half to two-thirds
of the activity in brain and liver homogenates is located in the
soluble fraction. Supernatant activity increases in these organs to a
maximum during...
In order to understand more about insulin behavior in solution,
Zn-free insulin was modified by adding polyglycyl chains to the
molecule and then observing the effect of the peptide on the behavior
of insulin under various conditions.
NCA-glycine (N-Carboxyglycine anhydride) of high purity was
reacted with Zn-free insulin in aqueous...
The effects of different levels of copper in the diet on growth
rates, blood and liver copper concentrations, hemoglobin levels,
and cytochrome c oxidase activities were determined in the cotton
rat. The response of the cotton rat to different levels of copper was
analagous to that of the common laboratory...
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...
Massive die-offs of Bufo bufo gargarizans were observed in May 2008 in Mangwal
Gee, Korea. To find out the causes for this disaster several different elements
were examined: pH, total nitrogen, dissolved oxygen (DO), and dissolved heavy
metal, suspension, introduced species, habitat change, disease, temperature
changes, and precipitation and humidity....
In a search for designed materials that mimic those found in biological systems, combining polymers with inorganic materials in sol-gel chemistry processes has gained momentum in the research world since the 1990's. This work methodically investigated the properties of several related polymer-SiO₂ hybrids prepared by a simple methodology that could...
More that just magnificent views of atoms and
molecules, Scanning Tunneling Microscopy, STM, images have
the potential to answer some fundamental questions relating
to surface molecular dynamics and bonding characteristics of
localized species versus more common analytical tools that
provide average of bulk sample information. A special
feature of the...