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Full-Text Articles in Chemistry

Spin Label Studies Of Radical Reduction In Normal And Sickle Erythrocyte Membranes Associated With Antioxidants, Yin Zhang Jan 1992

Spin Label Studies Of Radical Reduction In Normal And Sickle Erythrocyte Membranes Associated With Antioxidants, Yin Zhang

Dissertations

No abstract provided.


Low Temperature Spectroscopic And Annealing Studies Of Disordered Organic Solids, Dwayne L. Labrake Jan 1992

Low Temperature Spectroscopic And Annealing Studies Of Disordered Organic Solids, Dwayne L. Labrake

Dissertations

No abstract provided.


Remote Dianions In The Synthesis Of Indolizidine Alkaloids, Diana L. C. Green Green Jan 1992

Remote Dianions In The Synthesis Of Indolizidine Alkaloids, Diana L. C. Green Green

Dissertations

No abstract provided.


Site-Specific Binding Constants For Actinomycin D On Dna Determined From Footprinting Studies, Jerry Goodisman, Robert Rehfuss, Brian Ward, James C. Dabrowiak Sep 1991

Site-Specific Binding Constants For Actinomycin D On Dna Determined From Footprinting Studies, Jerry Goodisman, Robert Rehfuss, Brian Ward, James C. Dabrowiak

Chemistry - All Scholarship

We report site-specific binding constants for the intercalating anticancer drug actinomycin D (Act-D), binding to a 139-base-pair restriction fragment from pBR 322 DNA. The binding constants are derived from analysis of footprinting experiments, in which the radiolabeled 139-mer is cleaved using DNase I, the cleavage products undergo gel electrophoresis, and, from the gel autoradiogram, spot intensities, proportional to amounts of cleaved fragments, are measured. A bound drug prevents DNase I from cleaving at -7 bonds, leading to decreased amounts of corresponding fragments. With the radiolabel on the 3’ end of the noncoding strand (A-label), we measured relative amounts of 54 …


Structural Changes And Enhancements In Dnase I Footprinting Experiments?, Jerry Goodisman, James C. Dabrowiak Sep 1991

Structural Changes And Enhancements In Dnase I Footprinting Experiments?, Jerry Goodisman, James C. Dabrowiak

Chemistry - All Scholarship

In footprinting experiments, an increase in DNA cleavage with addition of ligand to a system may be due to a ligand-induced structural change. Ligand binding also enhances cleavage by displacing the cleavage agent from ligand-binding sites, thus increasing its concentration elsewhere. The theory and characteristics of this mass-action enhancement are given, and it is shown how it may be recognized. Results of DNase I footprinting of small oligomers, with actinomycin D as ligand, are analyzed to reveal which enhancements are due to mass action, and which can reasonably be ascribed to structural changes. Patterns in the footprinting plots from our …


Surface Tension Of A Charged And Polarized System, Jerry Goodisman Aug 1991

Surface Tension Of A Charged And Polarized System, Jerry Goodisman

Chemistry - All Scholarship

Usually, the formula for the surface tension of a planar charged and polarized interface is obtained from that for a system involving only short-range forces, y = - dz [p - px(z)] by replacing the tangential pressure p , by p , + E2/8u. Problems with this include (a) p, is no longer explicitly defined, (b) the electrostatic stress term E2/8 pi is not correct in general but only if polarization is proportional to density of polarizable species, (c) the derivation of the formula in terms of p and p, involves calculating the work to expand a volume containing the …


Formation Of Pentosidine During Nonenzymatic Browning Of Proteins By Glucose, Daniel G. Dyer, James A. Blackledge, Suzanne R. Thorpe, John W. Baynes Jun 1991

Formation Of Pentosidine During Nonenzymatic Browning Of Proteins By Glucose, Daniel G. Dyer, James A. Blackledge, Suzanne R. Thorpe, John W. Baynes

Faculty Publications

A fluorescent compound has been detected in proteins browned during Maillard reactions with glucose in vitro and shown to be identical to pentosidine, a pentose- derived fluorescent cross-link formed between arginine and lysine residues in collagen (Sell, D. R., and Monnier, V. M. (1989) J. Biol. Chem. 264, 21597- 2 1602). Pentosidine was the major fluorophore formed during nonenzymatic browning of ribonuclease and lysozyme by glucose, but accounted for <1% of nondisulfide cross-links in protein dimers formed during the reaction. Pentosidine was formed in greatest yields in reactions of pentoses with lysine and arginine in model systems but was also formed from glucose, fructose, ascorbate, Amadori compounds, 3-deoxyglucosone, and other sugars. Pentosidine was not formed from peroxidized polyunsaturated fatty acids or malondialdehyde. Its formation from carbohydrates was inhibited under nitrogen or anaerobic conditions and by aminoguanidine, an inhibitor of advanced glycation and browning reactions. Pentosidine was detected in human lens proteins, where its concentration increased gradually with age, but it did not exceed trace concentrations (55 Fmol/mol lysine), even in the 80-year-old lens. Although its precise carbohydrate source in vivo is uncertain and it is present in only trace concentrations in tissue proteins, pentosidine appears to be a useful biomarker for assessing cumulative damage to proteins by nonenzymatic browning reactions with carbohydrates.


Decrease In Skin Collagen Glycation With Improved Glycemic Control In Patients With Insulin-Dependent Diabetes Mellitus, Timothy J. Lyons, Karen E. Bailie, Daniel G. Dyer, John A. Dunn, John W. Baynes Jun 1991

Decrease In Skin Collagen Glycation With Improved Glycemic Control In Patients With Insulin-Dependent Diabetes Mellitus, Timothy J. Lyons, Karen E. Bailie, Daniel G. Dyer, John A. Dunn, John W. Baynes

Faculty Publications

Glycation, oxidation, and nonenzymatic browning of protein have all been implicated in the development of diabetic complications. The initial product of glycation of protein, fructoselysine (FL), undergoes further reactions, yielding a complex mixture of browning products, including the fluorescent lysine-arginine cross-link, pentosidine. Alternatively, FL may be cleaved oxidatively to form N(epsilon)-(carboxymethyl)lysine (CML), while glycated hydroxylysine, an amino-acid unique to collagen, may yield N(epsilon)-(carboxymethyl)hydroxylysine (CMhL). We have measured FL, pentosidine, fluorescence (excitation = 328 nm, emission = 378 nm), CML, and CMhL in insoluble skin collagen from 14 insulin-dependent diabetic patients before and after a 4-mo period of intensive therapy to …


Coupled Kinetic Analysis Of Cleavage Of Dna By Esperamicin And Calicheamicin, Hiroko Kishlkawa, Ying-Ping Jiang, Jerry Goodisman Nov 1990

Coupled Kinetic Analysis Of Cleavage Of Dna By Esperamicin And Calicheamicin, Hiroko Kishlkawa, Ying-Ping Jiang, Jerry Goodisman

Chemistry - All Scholarship

A coupled kinetic analysis of esperamicin, calicheamicin, and DNase I cleavage of covalently closed circular PM2 DNA has been carried out. Analysis of the optical density data derived from agarose gel electrophoresis experiments shows that esperamicin A,, like the hydrolytic enzyme DNase I, produces mainly single-strand breaks in DNA. These agents cause covalently closed circular form I DNA to be initially converted to nicked circular form I1 DNA. However, the ratio of the rate constant for this process (k,') to that associated with conversion of form I1 to linear form I11 DNA ( k i ) is not consistent with …


Thermodynamic Data From Drug-Dna Footprinting Experiments, James C. Dabrowiak, Jerry Goodisman, Koren Kissinger Apr 1990

Thermodynamic Data From Drug-Dna Footprinting Experiments, James C. Dabrowiak, Jerry Goodisman, Koren Kissinger

Chemistry - All Scholarship

Sequence-dependent thermodynamic quantities for the antiviral agent netropsin and a related bis(N-methylimidazole) dipeptide, lexitropsin, have been determined by DNase I footprinting techniques. The primary data are autoradiographic spot intensities derived from 10 footprinting experiments carried out in the temperature range 0-45 OC. After exclusion effects due to overlapped drug sites on DNA and redistribution phenomena associated with the enzyme were accounted for, sequence-dependent binding constants for the two ligands were calculated. Our approach does not require an independent determination of the free drug concentration, which is calculated, with individual site binding constants, by using only footprinting data. The temperature dependence …


Quantitative Footprinting Analysis. Binding To A Single Site, Robert Rehfuss, Jerry Goodisman, James C. Dabrowiak Aug 1989

Quantitative Footprinting Analysis. Binding To A Single Site, Robert Rehfuss, Jerry Goodisman, James C. Dabrowiak

Chemistry - All Scholarship

The theory for measuring ligand binding constants from footprinting autoradiographic data associated with a single binding site is derived. If the ligand and DNA cleavage agent compete for a common site, the spot intensities are not proportional to the amount of DNA not blocked by ligand. The analysis of a single site is experimentally illustrated by using results for the anticancer drug actinomycin D interacting with the duplex d(TAGCGCTA)2 as probed with the hydrolytic enzyme DNase I.


Synthesis Of Highly-Strained Gem-Difluoro Compounds By Reaction Of Difluoromethylene With Cycloalkenes, Deyi Yang May 1989

Synthesis Of Highly-Strained Gem-Difluoro Compounds By Reaction Of Difluoromethylene With Cycloalkenes, Deyi Yang

Theses

Trans-Cyclooctene is thought to be more reactive than cis-cyclooctene due to its trans-structure. When cis or trans-clooctene reacts with difluormethylene (:CF2), trans-9,9-difluorobicyclo[ 6,1,0] nonane was generated in much higher yield than cis-9,9-difluorobicyclo[6,1,0]nonane. [PhCF3P+CF2Br]Br- was chosen to be the difluoromethylene precursor in this study. The reason was that the reaction condition for trans-cyclooctene and :CF2 should be at low temperature. Only [PhCF3P+CF2Br]Br- could generate CF2 at lower temperature (e.g. room temperature). We succeeded in the synthesis of trans-9,9-difluorobicyclo[6,1,0]nonane and its cis isomer and …


Quantitative Footprinting Analysis Using A Dna-Cleaving Metalloporphyrin Complex+, James C. Dabrowiak, Brian Ward, Jerry Goodisman Dec 1988

Quantitative Footprinting Analysis Using A Dna-Cleaving Metalloporphyrin Complex+, James C. Dabrowiak, Brian Ward, Jerry Goodisman

Chemistry - All Scholarship

The results of quantitative footprinting studies involving the antiviral agent netropsin and a DNA-cleaving cationic metalloporphyrin complex are presented. An analysis of the footprinting autoradiographic spot intensities using a model previously applied to footprinting studies involving the enzyme DNase I [Ward, B., Rehfuss, R., Goodisman, J., & Dabrowiak, J. C. (1988) Biochemistry 27, 1198-12051 led to very low values for netropsin binding constants on a restriction fragment from pBR-322 DNA. In this work, we show that, because the porphyrin binds with high specificity to DNA, it does not report site loading information in the same manner as does DNase I. …


Inulin-125I-Tyramine, An Improved Residualizing Label For Studies On Sites Of Catabolism Of Circulating Proteins, Janet L. Maxwell, John W. Baynes, Suzanne R. Thorpe Oct 1988

Inulin-125I-Tyramine, An Improved Residualizing Label For Studies On Sites Of Catabolism Of Circulating Proteins, Janet L. Maxwell, John W. Baynes, Suzanne R. Thorpe

Faculty Publications

Residualizing labels for protein, such as dilactitol-125I-tyramine (125I-DLT) and cellobiitol-125I-tyramine, have been used to identify the tissue and cellular sites of catabolism of long-lived plasma proteins, such as albumin, immunoglobulins, and lipoproteins. The radioactive degradation products formed from labeled proteins are relatively large, hydrophilic, resistant to lysosomal hydrolases, and accumulate in lysosomes in the cells involved in degradation of the carrier protein. However, the gradual loss of the catabolites from cells (t1/2 approximately 2 days) has limited the usefulness of residualizing labels in studies on longer lived proteins. We describe here a higher molecular weight (Mr approximately 5000), more efficient …


Oxidative Degradation Of Glucose Adducts To Protein: Formation Of 3-(NE-Lysino)-Lactic Acid From Model Compounds And Glycated Proteins, Mahtab U. Ahmed, John A. Dunn, Michael D. Walla, Suzanne R. Thorpe, John W. Baynes Jun 1988

Oxidative Degradation Of Glucose Adducts To Protein: Formation Of 3-(NE-Lysino)-Lactic Acid From Model Compounds And Glycated Proteins, Mahtab U. Ahmed, John A. Dunn, Michael D. Walla, Suzanne R. Thorpe, John W. Baynes

Faculty Publications

The chemistry of Maillard or browning reactions of glycated proteins is being studied in model systems in vitro in order to characterize potential reaction pathways and products in biological systems. In previous work with the Amadori rearrangement product N alpha-formyl-N epsilon-fructoselysine (fFL), an analog of glycated lysine residues in proteins, we showed that fFL was oxidatively cleaved between C-2 and C-3 of the carbohydrate chain to yield N epsilon-carboxymethyllysine (CML) and D-erythronic acid. We then detected CML in proteins glycated in vitro, as well as in human lens proteins and collagen in vivo (Ahmed, M. U., Thorpe, S. R., and …


A Cytochemical Study Of The Transcriptional And Translational Regulation Of Nuclear Transition Protein 1 (Tp1), A Major Chromosomal Protein Of Mammalian Spermatids, Mohammad A. Heidaran, Richard M. Showman, Wilson Stephen Kistler May 1988

A Cytochemical Study Of The Transcriptional And Translational Regulation Of Nuclear Transition Protein 1 (Tp1), A Major Chromosomal Protein Of Mammalian Spermatids, Mohammad A. Heidaran, Richard M. Showman, Wilson Stephen Kistler

Faculty Publications

Immunocytochemical localization and in situ hybridization techniques were used to investigate the presence of spermatid nuclear transition protein 1 (TP1) and its mRNA during the various stages of spermatogenesis in the rat. A specific antiserum to TP1 was raised in a rabbit and used to show that TP1 is immunologically crossreactive among many mammals including humans. During spermatogenesis the protein appears in spermatids as they progress from step 12 to step 13, a period in which nuclear condensation is underway. The protein is lost during step 15. An asymmetric RNA probe generated from a TP1 cDNA clone identified TP1 mRNA …


Determination Of Netropsin-Dna Binding Constants From Footprinting Data, Brian Ward, Robert Rehfuss, Jerry Goodisman, James C. Dabrowiak Sep 1987

Determination Of Netropsin-Dna Binding Constants From Footprinting Data, Brian Ward, Robert Rehfuss, Jerry Goodisman, James C. Dabrowiak

Chemistry - All Scholarship

A theory for deriving drug-DNA site binding constants from footprinting data is presented. Plots of oligonucleotide concentration, as a function of drug concentration, for various cutting positions on DNA are required. It is assumed that the rate of cleavage at each nucleotide position is proportional to the concentration of enzyme at that nucleotide and to the probability that the nucleotide is not blocked by drug. The probability of a nucleotide position not being blocked is calculated by assuming a conventional binding equilibrium for each binding site with exclusions for overlapping sites. The theory has been used to evaluate individual site …


Observation Of An Oxygen Isotope Effect In Yba2Cu3O7, Kevin J. Leary, Hans Conrad Zur Loye, Steven W. Keller, Tanya A. Faltens, William K. Ham, James N. Michaels, Angelica M. Stacy Sep 1987

Observation Of An Oxygen Isotope Effect In Yba2Cu3O7, Kevin J. Leary, Hans Conrad Zur Loye, Steven W. Keller, Tanya A. Faltens, William K. Ham, James N. Michaels, Angelica M. Stacy

Faculty Publications

A small decrease in Tc of 0.3 K to 0.5 K is observed when as much as 90% of the 16O in YBa2Cu3O7 is substituted with18O. This result is consistent with our observation that there is an oxygen isotope effect in La1.85Sr0.15CuO4, but in contrast with previous reports that there is no isotope effect for YBa2Cu3O7. This new result suggests that phonons play an important role in the electron-pairing mechanism in YBa2Cu3O7.


Observation Of An Isotope Shift In The Superconducting Transition Temperature Of La1.85Sr0.15Cuo4, Tanya A. Faltens, William K. Ham, Steven W. Keller, Kevin J. Leary, James N. Michaels, Angelica M. Stacy, Hans Conrad Zur Loye, Donald E. Morris, T W. Barbee Iii, Marvin L. Cohen, Cohen S. Hoen, A Zettl Aug 1987

Observation Of An Isotope Shift In The Superconducting Transition Temperature Of La1.85Sr0.15Cuo4, Tanya A. Faltens, William K. Ham, Steven W. Keller, Kevin J. Leary, James N. Michaels, Angelica M. Stacy, Hans Conrad Zur Loye, Donald E. Morris, T W. Barbee Iii, Marvin L. Cohen, Cohen S. Hoen, A Zettl

Faculty Publications

An oxygen isotope shift is observed in superconducting La1.85Sr0.15CuO4 when 18O is substituted partially for 16O; the superconducting transition temperature Tc is lowered by 0.3 to 1.0 K in different samples. We examine these results using conventioanl phonon-mediated BCS theory and conclude that, for La1.85Sr0.15CuO4, phonons play an important role in the pairing mechanism.


Search For Isotope Effect In Superconducting Y-Ba-Cu-O, L C. Bourne, M F. Crommie, A Zettl, Hans Conrad Zur Loye, S W. Keller, K L. Leary, Angelica M. Stacy, K J. Chang, Marvin L. Cohen, Donald E. Morris Jun 1987

Search For Isotope Effect In Superconducting Y-Ba-Cu-O, L C. Bourne, M F. Crommie, A Zettl, Hans Conrad Zur Loye, S W. Keller, K L. Leary, Angelica M. Stacy, K J. Chang, Marvin L. Cohen, Donald E. Morris

Faculty Publications

An isotope effect has been searched for in the high-Tc, superconductor YBa2Cu307 —b through substitution of 180 for 16O. No shift in the superconducting transition temperature T, is observed by electrical resistivity or magnetic susceptibility measurements. We discuss the implications of this result for mechanisms of superconductivity in the high-T, oxides.


Effect Of Phosphate On The Kinetics And Specificity Of Glycation Of Protein, Nancy G. Watkins, Carolyn I. Neglia-Fisher, Daniel G. Dyer, Suzanne R. Thorpe, John W. Baynes May 1987

Effect Of Phosphate On The Kinetics And Specificity Of Glycation Of Protein, Nancy G. Watkins, Carolyn I. Neglia-Fisher, Daniel G. Dyer, Suzanne R. Thorpe, John W. Baynes

Faculty Publications

The glycation (nonenzymatic glycosylation) of several proteins was studied in various buffiner os rder to assess the effects of buffering ions on the kinetics and specificity of glycation of protein. Incubation of RNase with glucose in phosphate buffer resulted in inactivation of the enzyme because of preferential modification of lysine residues ino r near the activsei te. In contrast, in the cationic buffers, 3-(N-morpholino)propanesulfonic acid and 3-(N-tris(hydroxymethyl)rnethylamino)- 2-hydroxypropanesulfonica cid, the kineticso f glycation of RNase were decreased 2- to 3-fold, there was a decrease in glycation of active site versus peripheral lysines, and the enzyme was resistant to inactivation by …


Applications Of The Semiclassical Spectral Method To Nuclear, Atomic, Molecular, And Polymeric Dynamics, M. L. Koszykowski, George A. Pfeffer, Donald W. Noid Jan 1987

Applications Of The Semiclassical Spectral Method To Nuclear, Atomic, Molecular, And Polymeric Dynamics, M. L. Koszykowski, George A. Pfeffer, Donald W. Noid

Chemistry Faculty Publications

Nonlinear dynamics plays a dominant role in a variety of important problems in chemical physics. Examples are unimolecular reactions,’ infrared multiphoton decomposition of molecules,’ the pumping process of the gamma ray laser,’ dissociation of vibrationally excited state-selected van der Waals’s complexes,’ and many other chemical and atomic processes. The present article discusses recent theoretical studies on the quasi-periodic and chaotic dynamical aspects of vibrational-rotational states of atomic, nuclear, and molecular systems using the semiclassical spectral method (SSM).’ We note that the coordinates, momenta, and so on, are found using classical mechanics in the studies included in this review. Consequently, certain …


Identification Of Fibroblasts As A Major Site Of Albumin Catabolism In Peripheral Tissues, Jeffrey L. Strobel, Susan G. Cady, Thomas K. Borg, Louis Terracio, John W. Baynes, Suzanne R. Thorpe Jun 1986

Identification Of Fibroblasts As A Major Site Of Albumin Catabolism In Peripheral Tissues, Jeffrey L. Strobel, Susan G. Cady, Thomas K. Borg, Louis Terracio, John W. Baynes, Suzanne R. Thorpe

Faculty Publications

Rat serum albumin has been labeledw ith dilactitollZ5I- tyramine,( 12‘I-DLT) a radioactive tracer which remains entrappedw ithin lysosomes following cellular uptake and degradation of the carrier protein. Similar kinetics of clearance from the rat circulation were observed for albumin labeled conventionally with lZsI or 12‘I-DLT-albumin, both proteinhsa ving circulating half-lives of -2.2 days. In contrast, the recovery of whole body radioactivity had half-lives of -2.2 and 5.1 days, respectively, for the two protein preparations, indicating substantial retention of degradation products derived from catabolism of ”‘I-DLT-albumin. Measurement of total and acid-soluble radioactivity in tissues 2 or 4 days after injection of …


Identification Of N Epsilon-Carboxymethyllysine As A Degradation Product Of Fructoselysine In Glycated Protein, Mahtab U. Ahmed, Suzanne R. Thorpe, John W. Baynes Apr 1986

Identification Of N Epsilon-Carboxymethyllysine As A Degradation Product Of Fructoselysine In Glycated Protein, Mahtab U. Ahmed, Suzanne R. Thorpe, John W. Baynes

Faculty Publications

The chemistry of Maillard or browning reactionosf glycated proteins was studied using the model compound, Nu-formyl-W-fructoselysine(f FL), an analog of glycated lysine residues in protein. Incubation of fFL (15 mM) at physiological pH and temperature in 0.2 M phosphate buffer resulted in formation of lVcarboxymethyllysine (CML) in about 40% yield after 15 days. CML was formed by oxidative cleavage of fFL between C-2 and C-3 of the carbohydrate chain and erythronic acid (EA) was identified a s , the split product formed in the reaction. Neither CML nor EA was formed from fFL under a nitrogen atmosphere. The rate of …


Calculated Electronic Profiles For Liquid-Metal Surfaces, Jerry Goodisman Oct 1985

Calculated Electronic Profiles For Liquid-Metal Surfaces, Jerry Goodisman

Chemistry - All Scholarship

The electronic density profile for a liquid-metal surface can be calculated by solving the self-consistent Lang-Kohn equations for the electronic wave functions. One requires a surface density profile for the ion cores, which enters the electrostatic and pseudopotential parts of the electronic Hamiltonian. We use oscillatory profiles, suggested by those found by molecular-dynamics simulations on a pseudoatom model. Calculating surface potentials and work functions, we obtain excellent agreement with experiment (within 0.2 eV). It is shown that use of either step-function ion profiles or a simple variational method leads to serious errors (12 eV) for these quantities.


Glycation Of Amino Groups In Protein, Nancy G. Watkins, Suzanne R. Thorpe, John W. Baynes Sep 1985

Glycation Of Amino Groups In Protein, Nancy G. Watkins, Suzanne R. Thorpe, John W. Baynes

Faculty Publications

Ribonuclease A has been used as a model protein for studying the specificity of glycation of amino groups in protein under physiological conditions (phosphate buffer, pH 7.4, 37 “C). Incubation of RNase with glucose led to an enhanced rate of inactivation of the enzyme relative to the rate of modification of lysine residues, suggesting preferential modification of active site lysine residues. Sites of glycation of RNase were identified by amino acid analysis of tryptic peptides isolated by reverse-phase high pressure liquid chromatography and phenylboronate affinity chromatography. Schiff base adducts were trapped with Na- BH&N and the a-amino group of Lys-1 …


Characterization Of Glycated Proteins By 13C Nmr Spectroscopy, Carolyn I. Neglia, Helga J. Cohen, Albert R. Garber, Suzanne R. Thorpe, John W. Baynes Sep 1984

Characterization Of Glycated Proteins By 13C Nmr Spectroscopy, Carolyn I. Neglia, Helga J. Cohen, Albert R. Garber, Suzanne R. Thorpe, John W. Baynes

Faculty Publications

13C NMR spectroscopy has been used to characterize Amadori (ketoamine) adducts formed by reaction of [2-13C]glucose with free amino groups of protein. The spectra of glycated proteins were acquired in phosphate buffer at pH 7.4 and were interpreted by reference to the spectra of model compounds, N alpha-formyl-N epsilon-fructose-lysine and glycated poly-L-lysine (GlcPLL). The anomeric carbon region of the spectrum (approximately 90-105 ppm) of glycated cytochrome c was superimposable on that of N alpha-formyl-N epsilon-fructose-lysine, and contained three peaks characteristic of the alpha- and beta-furanose and beta-pyranose anomers of Amadori adducts to peripheral lysine residues on protein (pK alpha approximately …


A Three Part Research Report: The Synthesis Of Potential Insecticides, N-(4-Heteroaryloxybenzoyl)-N'-(2,4-Dichlorobenzoyl) Hydrazines: A Reinvestigation Of Hexamethylphosphoramide With Ketoximes; Regioselective Fluoralkoxylation And Polyfluoroalkoxylation Of Activated Dihalobenzenes And Dihaloheterocycles, Gary A. Decrescenzo Jan 1984

A Three Part Research Report: The Synthesis Of Potential Insecticides, N-(4-Heteroaryloxybenzoyl)-N'-(2,4-Dichlorobenzoyl) Hydrazines: A Reinvestigation Of Hexamethylphosphoramide With Ketoximes; Regioselective Fluoralkoxylation And Polyfluoroalkoxylation Of Activated Dihalobenzenes And Dihaloheterocycles, Gary A. Decrescenzo

Retrospective Theses and Dissertations

This report discusses research in three areas of organic synthesis: The synthesis of potential insecticides; the reinvestigation of the reaction of hexamethylphosphoramide with ketoximes; and the regioselective fluoroalkoxylation and polyfluoroalkoxylation of activated dihalobenzenes and dihaloheterocycles. In Part I, a series of N-(4-heteroaryloxybenzoyl)-N'-(2, 3-dichlorobenzoyl) hydrazines are synthesized, and attempts at cyclic dehydration to the corresponding 2, 5-disubstituted-1, 3, 4-oxadiazoles are discussed. In Part II, the synthesis of N, N-dimethyl-N'-aryl amidines by the reaction of aryl alkyl and diaryl ketoximes with HMPA is discussed. In Part III, a series of activated dihalobenzenes and dihaloheterocycles are reacted with sodium trifluoroethoxide to study the …


Oxidation Of Valencene To Nootkatone, Tung F. Chen Jan 1984

Oxidation Of Valencene To Nootkatone, Tung F. Chen

Retrospective Theses and Dissertations

The liquid phase autoxidation of the readily available sesquiterpene valencene to the commercially important perfuming agent nootkatone utilizing gaseous oxygen at atmospheric pressure has been investigated. Catalyst systems involving transition metal salts and complexes, and phase-transfer catalysts have been evaluated under different conditions of valencene concentration, catalyst concentration, reaction temperature, solvent and oxygen flow rate. Of eighteen candidate catalysts for the oxidation of valencene to nootkatone, chlorocarbonylbis (triphenylphosphine) iridium (Vaska's catalyst) demonstrated good activity and appeared to show the best potential for future work.


Copper And Barium As Dietary Discriminants: The Effects Of Diagenesis, J B. Lambert, S V. Simpson, Carole B. Szpunar, J E. Buikstra Jan 1984

Copper And Barium As Dietary Discriminants: The Effects Of Diagenesis, J B. Lambert, S V. Simpson, Carole B. Szpunar, J E. Buikstra

Chemistry: Faculty Publications and Other Works

In skeletons excavated from Woodland sites, copper and barium levels are found to have been contaminated by influx from the soil environment. Electron microprobe scans for both elements show build-up along the outer surface of femur cross sections. Elemental levels for Cu and Ba are lower in the femur or fibula than in the more porous rib. The distribution of Cu in the immediately surrounding soil is highly anisotropic. These observations indicate that Cu and Ba should not be used for dietary inferences about ancient populations without independent evidence that diagenesis is not important.