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Synthetic Applications Of The Photochemical Cycloaddition Reactions Of N-Acylindoles And Conformational Studies Of The Cycloadducts, Boke Zhang
Digitized Theses
The ability of a series of nitrogen-substituents to activate the cycloaddition photochemistry of indoles has been examined; the N-substituents were chosen in order to enable their removal following cycloaddition under mild neutral, acidic or basic conditions. N-substituted indoles, 17, 12 and 104c-g, were prepared in which the N-substituent is COPh, CO{dollar}\sb2{dollar}Et, CO{dollar}\sb2{dollar}CH{dollar}\sb2{dollar}CH{dollar}\sb2{dollar}SiMe{dollar}\sb3{dollar}, CO{dollar}\sb2{dollar}CH{dollar}\sb2{dollar}CH{dollar}\sb2{dollar}CN, CO{dollar}\sb2{dollar}Bu{dollar}\sp{lcub}\rm t{rcub}{dollar}, CO{dollar}\sb2{dollar}Ph, and CO{dollar}\sb2{dollar}CH{dollar}\sb2{dollar}Ph, respectively.;The silylethoxycarbonyl group of photoadducts derived from 104c can be removed by treatment of the adduct with fluoride ion in dichloromethane, the tert-butyloxycarbonyl group of adducts derived from 104e by treatment with trifluoroacetic acid at room temperature; the benzyloxycarbonyl group of adducts …
The Characterization And Chemical Reactivity Of Airborne Particulates, Marco Eugenio Giuliacci
The Characterization And Chemical Reactivity Of Airborne Particulates, Marco Eugenio Giuliacci
Digitized Theses
The characterization of airborne particulates requires the use of sensitive analytical techniques such as SIMS, AUGER, XPS, SEM/EDX, EMP, XRF, IOP-MS and XRD. These techniques supply information on trace element distributions of single or bulk particulates. In addition, we have found that the kinetics of the conversion of S(IV) to S(VI) in contact with particulate matter is useful to identify high levels of catalytic material, possibly of anthropogenic origins, present in the air mass. The reactivity of the airborne particulate matter can be combined with analytical methods to help in the identification of particulate sources. In addition, trace metal analysis …
Radiotracers For The Angiotensin System, Vincenzo Quiquero
Radiotracers For The Angiotensin System, Vincenzo Quiquero
Digitized Theses
Angiotensin converting enzyme (ACE), a dipeptidyl carboxypeptidase, is one of the enzyme components of the renin-angiotensin-aldosterone system. ACE is responsible for the production of angiotensin II, a potent vasoconstrictor, and for the inactivation of the potent vasodepressor peptide bradykinin. The enzyme is a vascular endothelial component of many tissues (i.e. lungs, kidney, preoptic region of brain) and has been shown to be localized on the lumenal surface of the vascular endothelium. Diseases involving granuloma (i.e. sarcoidosis, silicosis, asbestosis) are known to change the distribution of ACE and to cause hypertension. A radiolabelled pharmaceutical which binds with ACE could permit the …
Regulation Of Gene Expression Of Surfactant-Associated Proteins In Developing Rabbit Lung, Jiejing Xu
Regulation Of Gene Expression Of Surfactant-Associated Proteins In Developing Rabbit Lung, Jiejing Xu
Digitized Theses
Pulmonary surfactant replacement therapy and antenatal glucocorticoid administration are the two treatment strategies used for Respiratory Distress Syndrome. Because of the important roles surfactant-associated proteins play in surfactant function, understanding the mechanisms involved in regulation of the genes encoding for the proteins in fetal development or upon glucocorticoid treatment is therefore of paramount importance in the overall design of an effective treatment regimen. We attempted in this project to investigate the developmental and glucocorticoid regulation of three surfactant proteins, SP-A, SP-B and SP-C, using the rabbit as a model. The mRNA levels for these three proteins were examined in developing …
Segregation And Oxidation Studies Of Aluminum-Lithium And Aluminum-Magnesium Alloys, Frank Joseph Esposto
Segregation And Oxidation Studies Of Aluminum-Lithium And Aluminum-Magnesium Alloys, Frank Joseph Esposto
Digitized Theses
Auger electron spectroscopy, work function measurements, low energy electron diffraction, nuclear reaction analysis, dynamic/static secondary ion mass spectrometry, thermal desorption spectroscopy, and synchrotron radiation-photoemission spectroscopy have been used to investigate the segregation and oxidation of (111) oriented Al-6.5(at.%)Li and (110) oriented Al-1.45(at%)Mg single crystal binary alloys. The resulting Li and Mg equilibrium surface concentrations are found to be 0.16 and 0.47 respectively. For both alloys, the increase in surface concentration was associated with a decrease in {dollar}\Delta\phi{dollar}. {dollar}\surd 3\rm x\surd 3R30\sp\circ{dollar} and c(2x2) superlattices were observed at the equilibrium surface concentrations for the Al-Li and Al-Mg alloys respectively. This is …
Aspects Of Pulmonary Surfactant Metabolism, Rudolf A. Veldhuizen
Aspects Of Pulmonary Surfactant Metabolism, Rudolf A. Veldhuizen
Digitized Theses
Pulmonary surfactant stabilizes the lung by reducing the surface tension at the air liquid interface of the alveolus. Phosphatidylcholine represents the principal component of surfactant (70% by weight), other lipids account for 20% of surfactant and the remaining 10% is protein. Four surfactant-associated proteins have been identified, surfactant associated protein (SP) SP-A, SP-B, SP-C and SP-D.;This thesis describes the investigations on the following aspects of surfactant metabolism: (1) phosphatidylcholine synthesis, (2) alterations in surfactant after lung transplantation and (3) mechanisms of alveolar surfactant subtype conversion.;(1) The de novo synthesis of acyl-specific phosphatidylcholine via the acylation of glycerol-3-phosphocholine (GPC) has been …
Ph Optimization Of Nucleophilic Reactions And Mechanisms Of Reactions Of Sulfonyl Chlorides, Joe Ying Lam
Ph Optimization Of Nucleophilic Reactions And Mechanisms Of Reactions Of Sulfonyl Chlorides, Joe Ying Lam
Digitized Theses
This thesis consists of four chapters all involving the chemistry of sulfonyl chlorides in water.;Chapter 1 describes the mechanisms of the reactions of alkanesulfonyl chlorides with water with and without added nucleophiles. Evidence is provided that the hydrolysis of alkanesulfonyl chlorides proceeds (a) at low pH, by S{dollar}\sb{lcub}\rm N{rcub}{dollar}2-S attack of water, (b) at intermediate pH, by rate determining attack of hydroxide anion to form sulfene which is then trapped by water, and (c) at high pH, by way of sulfene both formed and trapped by hydroxide anion. Among the following pathways observed in the reaction of alkanesulfonyl chlorides with …
Genomic Characterization Of Steroid Hormone-Binding Globulins, D Alan Underhill
Genomic Characterization Of Steroid Hormone-Binding Globulins, D Alan Underhill
Digitized Theses
Sex-hormone binding globulin (SHBG) and corticosteroid binding globulin (CBG) are the major plasma transport proteins for sex-steroids and glucocorticoids, respectively, and may impact directly upon steroid hormone bioavailability to target cells. Androgen binding protein (ABP) is closely related to SHBG and is believed to maintain an androgenic environment for sperm maturation. The isolation of SHBG-related cDNAs from human testis and a corresponding transcription unit indicates that SHBG and ABP are encoded by the same gene. In addition, the SHBG/ABP gene gives rise to two novel testicular transcripts through a process of alternative splicing. The putative proteins encoded by these transcripts …
Comparative Studies Of The Effects Of Menogaril And Adriamycin On Cell Morphology And Membrane Function Of Parental And Multidrug Resistant Cells, Stewart E. Daly
Comparative Studies Of The Effects Of Menogaril And Adriamycin On Cell Morphology And Membrane Function Of Parental And Multidrug Resistant Cells, Stewart E. Daly
Digitized Theses
This project was initiated to obtain a better understanding of the cellular mode of action of the anthracycline drug menogaril. Comparative experiments demonstrated that menogaril was as cytotoxic as adriamycin against parental AUX B1 Chinese hamster ovary cells (CHO), however, multidrug resistant (MDR) CH{dollar}\sp{lcub}\rm R{rcub}{dollar}C5 CHO cells, which are characterized by the overexpression of P-glycoprotein relative to the parental cells, were less resistant to menogaril. When parental and MDR cells were exposed to equitoxic concentrations of both drugs, menogaril accumulated to a higher level, however, both drugs accumulated to a significantly higher level in the MDR cells. Immediately after exposure …
Nucleophilic Reactions Of Sulfonyl And Carbonyl Compounds, Darryl Frederick Klassen
Nucleophilic Reactions Of Sulfonyl And Carbonyl Compounds, Darryl Frederick Klassen
Digitized Theses
This thesis contains topics in organic sulfur chemistry and general physical organic chemistry. In the first chapter a pH rate profile (log {dollar}k\sb{lcub}\rm obs{rcub}{dollar} vs pH) was determined for the hydrolysis of ethylene sulfone (1) over the pH range from 4 to 11.5 at 75{dollar}\sp\circ{dollar}C. The rate constant {dollar}k\sb{lcub}\rm obs{rcub}{dollar} was found to be of the form {dollar}k\sb{lcub}\rm obs{rcub}{dollar} = {dollar}k\sb{lcub}\rm w{rcub}{dollar} + {dollar}k\sb{lcub}\rm OH{rcub}{dollar} (OH{dollar}\sp-{dollar}) where {dollar}k\sb{lcub}\rm w{rcub}{dollar} = (8.71 {dollar}\pm{dollar} 1.38) {dollar}\times{dollar} 10{dollar}\sp{lcub}-5{rcub}{dollar} s{dollar}\sp{lcub}-1{rcub}{dollar} and {dollar}k\sb{lcub}\rm OH{rcub}{dollar} = (2.98 {dollar}\pm{dollar} 0.89) {dollar}\times{dollar} 10{dollar}\sp{lcub}-2{rcub}{dollar} M{dollar}\sp{lcub}-1{rcub}{dollar}s{dollar}\sp{lcub}-1{rcub}{dollar}. In the pH region that corresponds to the uncatalyed hydrolysis ({dollar}k\sb{lcub}\rm w{rcub}{dollar}, pH 4 …
High-Resolution Photoelectron Spectroscopy Using Synchrotron Radiation: Ligand Field And Vibrational Splitting And Chemical Effects On Linewidths, Jeffrey N. Cutler
High-Resolution Photoelectron Spectroscopy Using Synchrotron Radiation: Ligand Field And Vibrational Splitting And Chemical Effects On Linewidths, Jeffrey N. Cutler
Digitized Theses
High resolution photoelectron spectra of numerous Group IV, VII and VIII compounds have been recorded using a newly constructed photoelectron spectrometer based on the McPherson ESCA 36 hemispherical analyzer. This spectrometer is designed to make use of the high electron resolution and transmission of the analyzer coupled with the tunability and high photon resolution which is inherent in synchrotron radiation.;For the first time using this instrument, it has become possible to differentiate between three distinct core level broadening mechanisms: vibrational and ligand field splitting and a chemical effect on linewidths. Several I 4d photoelectron spectra of seven different iodine-containing compounds …
Studies Of The Behaviour Of Lipophilic Molecules In Model Membranes: Applications To Amphotericin B And Glycosphingolipids, Katherine S. Hamilton
Studies Of The Behaviour Of Lipophilic Molecules In Model Membranes: Applications To Amphotericin B And Glycosphingolipids, Katherine S. Hamilton
Digitized Theses
Our investigations have focused on two model membrane systems: liposomal amphotericin B and glycosphingolipids as minor components in phospholipid bilayers. Although amphotericin B and glycosphingolipids have very diverse biological functions, studying their respective behaviour and interactions in the context of a lipid bilayer is of prime importance.;The association of amphotericin B with lipid vesicles has proven to be a successful modality of treatment, with an antifungal activity that is closely tied to the physical nature (e.g. vesicle size and lipid composition) of the preparation. Using freeze-fracture electron microscopy, density gradient ultracentrifugation, and differential scanning calorimetry we have characterised the basic …
Electroless Reduction Of Gold(Iii) On Pyrite From Chloride Electrolytes, Jay Richard Mycroft
Electroless Reduction Of Gold(Iii) On Pyrite From Chloride Electrolytes, Jay Richard Mycroft
Digitized Theses
The electroless reduction of aqueous precious metal salts on arsenopyrite, galena, zinc blende, stibnite, wolframite and molybdenite was reported as early as 1870. Since this initial work, very little has been reported about the electroless reduction mechanism of gold(III) on pyrite, despite the geochemical importance of this reaction. Recently, surface analytical techniques have been used to study the chemical and morphological characteristics of laboratory-controlled metal deposition. Since the reduction of gold(III) on pyrite is rapid, surface analytical techniques have not been adequate to elucidate the entire mechanism.;On the other hand, electrochemical techniques in conjunction with surface analytical measurements have proven …
Structural And Biosynthetic Relationships Between The Beta And Epsilon Subunits Of Escherichia Coli F(1)-Atpase, Helmut Garry Dallmann
Structural And Biosynthetic Relationships Between The Beta And Epsilon Subunits Of Escherichia Coli F(1)-Atpase, Helmut Garry Dallmann
Digitized Theses
The zero length crosslink between the inhibitory {dollar}\epsilon{dollar} subunit and one catalytic {dollar}\beta{dollar} subunit of E. coli F{dollar}\sb1{dollar}-ATPase ({dollar}\alpha\sb3\beta\sb3\gamma\delta\epsilon{dollar}), induced by 1-ethyl-3- ((3-dimethylamino)propyl) -carbodiimide (EDC), was determined. A crosslinked CNBr fragment derived from {dollar}\beta{dollar}-{dollar}\epsilon{dollar} was identified by SDS-PAGE. Protein sequence analysis revealed the constituent peptides to be {dollar}\beta{dollar}-Asp-380--Met-431 and {dollar}\epsilon{dollar}-Glu-96--Met-138. {dollar}\beta{dollar}-Glu-381 was absent from cycle 2 indicating that it was one of the crosslinked residues, but no potential crosslinked residue in {dollar}\epsilon{dollar} was identified.;An {dollar}\epsilon{dollar} mutant with methionine replacing Val-112 ({dollar}\epsilon{dollar}V112M) was produced, incorporated into F{dollar}\sb1{dollar}, then crosslinked with EDC. A crosslinked CNBr fragment of {dollar}\beta{dollar}-{dollar}\epsilon{dollar}V112M was shown to contain …
Chemistry Of Binuclear And Cluster Complexes Of Ruthenium, Cobalt And Nickel, Hameed A. Mirza
Chemistry Of Binuclear And Cluster Complexes Of Ruthenium, Cobalt And Nickel, Hameed A. Mirza
Digitized Theses
The work described in this thesis is mainly focused on the synthesis, characterization and chemical reactivity of dinuclear and trinuclear phosphine substituted carbonyl complexes of Ru, Co and Ni. The thesis can be broadly classified into three sections. The first section comprising chapters 2 and 3, deals with the chemistry of dinuclear and trinuclear ruthenium complexes with dppm, bis(diphenylphosphino)methane, bridging ligands. The reaction mixture RuCl{dollar}\sb3{dollar}/dppm/NaBH{dollar}\sb4{dollar}/CO yielded mainly trans- (RuCl{dollar}\sb2{dollar}(dppm){dollar}\sb2{dollar}). However, when silver acetate was added to the reaction mixture prior to the reduction with NaBH{dollar}\sb4{dollar}, a high yield synthesis of (Ru{dollar}\sb2{dollar}({dollar}\mu{dollar}-CO)(CO){dollar}\sb4{dollar}({dollar}\mu{dollar}-dppm){dollar}\sb2{dollar}) was achieved. In addition, (RuH(CO)(dppm){dollar}\sb2{dollar}) {dollar}\sp+{dollar} and the electron …
Metal And Ring Oxidation In Metallophthalocyanines, Edward A. Ough
Metal And Ring Oxidation In Metallophthalocyanines, Edward A. Ough
Digitized Theses
Absorption and magnetic circular dichroism (MCD) spectra of neutral and oxidized magnesium and iron phthalocyanine (MgPc and FePc) are reported. Chemical, electrochemical and photochemical methods are employed in the generation of the stable {dollar}\pi{dollar}-cation radical of magnesium phthalocyanine. The broad absorption band at 500 nm is a "marker" band that verifies oxidation of the phthalocyanine ring. Variable temperature absorption and EPR spectra indicate that oxidized MgPc({dollar}-{dollar}1) exists in solution as a mixture of monomer ( (MgPc({dollar}-{dollar}1)) {dollar}\cdot\sp+{dollar})and dimer ( (MgPc({dollar}-{dollar}1)) {dollar}\sbsp{lcub}2{rcub}{lcub}++{rcub}{dollar}). Least squares and Simplex calculations were performed on the absorption and MCD spectra of MgPc({dollar}-{dollar}2) and MgPc({dollar}-{dollar}1) to determine …
Reaction And Oxidation Chemistry Of Molybdenum Oxide And Sulphide Surfaces, Perry Alan Spevack
Reaction And Oxidation Chemistry Of Molybdenum Oxide And Sulphide Surfaces, Perry Alan Spevack
Digitized Theses
Supported and unsupported molybdate films have served as the backbone as of the hydrodesulphurisation catalysts used for removing organo-sulphur compounds from light petroleum feedstocks. The catalyst material starts as one or more molybdenum (VI) oxide(s), but the oxidation state reduces to Mo(IV) during sulphidation. Despite the extensive analytical studies carried out on these systems over the past 25 years, the fundamental questions still remain--what is the nature of the catalytic site on the molybdate hydrodesulphurisation catalyst, and is the site identical on promoted and unpromoted catalysts?;A new approach to catalyst film preparation was developed using thin supported molybdate films. The …
In Search Of An Alternative Route To Germasilenes: The Synthesis And Chemistry Of (Halosilyl)Germanes, Umesh Ramji Parshotam
In Search Of An Alternative Route To Germasilenes: The Synthesis And Chemistry Of (Halosilyl)Germanes, Umesh Ramji Parshotam
Digitized Theses
This thesis describes attempts to prepare a germasilene, a compound containing a germanium-silicon double bond, by either a {dollar}\beta{dollar}-elimination reaction or a reductive elimination reaction.;The precursor, Mes{dollar}\sb2{dollar}HGeSiClMes{dollar}\sb2{dollar}, 1, (Mes = 2,4,6-trimethylphenyl) was prepared by the addition of Mes{dollar}\sb2{dollar}HGeLi to Mes{dollar}\sb2{dollar}SiCl{dollar}\sb2{dollar} in THF in excellent yield. We examined the effect of changing the nature of the solvent, leaving group, base and ligands on the reaction between 1 and base.;Mes{dollar}\sb2{dollar}ClGeSiClMes{dollar}\sb2,{dollar} 29, and Mes{dollar}\sb2{dollar}BrGeSiClMes{dollar}\sb2{dollar}, 30, prepared by the chlorination and bromination of 1 respectively, were treated with lithium naphthalenide (LiNp) in an attempt to prepare Mes{dollar}\sb2{dollar}Ge = SiMes{dollar}\sb2{dollar} by a reductive elimination reaction. …
Decay Of The Triplet State In A Porphyrin Quinone Molecule, David Donald Fraser
Decay Of The Triplet State In A Porphyrin Quinone Molecule, David Donald Fraser
Digitized Theses
Workers in this and many other labs have been studying photoinduced electron transfer seeking to understand the photochemical processes in photosynthesis. Closely related processes also constitute the basis of some photosensitive tissue diseases and of a wide variety of industrial applications. To study the photophysics unhindered by diffusion, a molecule composed of a freebase porphyrin covalently linked to a p-benzoquinone by an amide linkage was used.;A nanosecond laser flash photolysis apparatus permitted the observation of the porphyrin triplet state decay, with the quinone fully reduced or with it fully oxidized to allow enhanced quenching of the porphyrin triplet via electron …