Search Results - "Whitfield, Dennis M"

In a glycosylation reaction how does a hydroxylic nucleophile find the activated anomeric carbon? by Whitfield, Dennis M.

“…•Further examples of the lone pairs of α-face nucleophiles acting as antiperiplanar lone pairs.•A possible example of β-face nucleophiles using orbital…”
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General low-temperature reaction pathway from precursors to monomers before nucleation of compound semiconductor nanocrystals by Yu, Kui, Liu, Xiangyang, Qi, Ting, Yang, Huaqing, Whitfield, Dennis M., Y. Chen, Queena, Huisman, Erik J. C., Hu, Changwei

“…Little is known about the molecular pathway to monomers of semiconductor nanocrystals. Here we report a general reaction pathway, which is based on…”
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Utilizing CMP-Sialic Acid Analogs to Unravel Neisseria gonorrhoeae Lipooligosaccharide-Mediated Complement Resistance and Design Novel Therapeutics by Gulati, Sunita, Schoenhofen, Ian C, Whitfield, Dennis M, Cox, Andrew D, Li, Jianjun, St Michael, Frank, Vinogradov, Evgeny V, Stupak, Jacek, Zheng, Bo, Ohnishi, Makoto, Unemo, Magnus, Lewis, Lisa A, Taylor, Rachel E, Landig, Corinna S, Diaz, Sandra, Reed, George W, Varki, Ajit, Rice, Peter A, Ram, Sanjay

“…Neisseria gonorrhoeae deploys a novel immune evasion strategy wherein the lacto-N-neotetraose (LNnT) structure of lipooligosaccharide (LOS) is capped by the…”
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DFT studies of the ionization of alpha and beta glycopyranosyl donors by Whitfield, Dennis M.

“…Current attempts at mimicking the transition states (TSs) of glycosyl processing enzymes (GPEs) that proceed through TSs with a high degree of oxacarbenium ion…”
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Plausible transition states for glycosylation reactions by Whitfield, Dennis M.

“…[Display omitted] ► First attempt at including donor, acceptor, promoter, and solvent in glycoside formation modeling. ► Long range (2.725Ǻ) interactions of…”
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Exploring the Mechanism of Neighboring Group Assisted Glycosylation Reactions by Nukada, Tomoo, Berces, Attila, Zgierski, Marek Z, Whitfield, Dennis M

“…Glycosyl donors based on the 2,6-di-O-acyl-3,4-O-isopropylidene-d-galactopyranosyl-(leaving group) structure have been shown experimentally to have a high…”
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The two-conformer hypothesis: 2,3,4,6-tetra- O-methyl-mannopyranosyl and -glucopyranosyl oxacarbenium ions by Nukada, Tomoo, Bérces, Attila, Wang, LiJie, Zgierski, Marek Z., Whitfield, Dennis M.

“…[Display omitted] Computational chemistry can give information about the probable conformations of reactive intermediates that are difficult to determine…”
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Synthetic Archaeosome Vaccines Containing Triglycosylarchaeols Can Provide Additive and Long-Lasting Immune Responses That Are Enhanced by Archaetidylserine by Sprott, G. Dennis, Yeung, Angela, Dicaire, Chantal J., Yu, Siu H., Whitfield, Dennis M.

“…The relation between archaeal lipid structures and their activity as adjuvants may be defined and explored by synthesizing novel head groups covalently linked…”
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On the influence of solvent on the stereoselectivity of glycosylation reactions by Dorst, Kevin M, Engström, Olof, Angles d'Ortoli, Thibault, Mobarak, Hani, Ebrahemi, Azad, Fagerberg, Ulf, Whitfield, Dennis M, Widmalm, Göran

“…Methodology development in carbohydrate chemistry entails the stereoselective formation of C-O bonds as a key step in the synthesis of oligo- and…”
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Complications of modeling glycosylation reactions: can the anomeric conformation of a donor determine the glycopyranosyl oxacarbenium ring conformation? by Whitfield, Dennis M.

“…[Display omitted] ► Donor H-bonding, 1,6-anhydro formation, and O-2 electron rich C nucleophile complexes identified. ► Anomeric dihedral determines the ring…”
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Proton transfer and hydrogen bonding in glycosylation reactions by Whitfield, Dennis M., Guo, Jiatong

“…Creating general methods for stereospecific formation of glycosidic linkages is a long term goal of synthetic chemists. It has long been hoped that by…”
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Could Diastereoselectivity in the Presence of O-2 Chiral Nonparticipating Groups Be an Indicator of Glycopyranosyl Oxacarbenium Ions in Glycosylation Reactions? by Kumar, Rishi, Whitfield, Dennis M

“…Although long postulated, the existence of glycopyranosyl oxacarbenium ions as intermediates or transition states (TS) in chemical glycosylation reactions has…”
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Low-Temperature Approach to Highly Emissive Copper Indium Sulfide Colloidal Nanocrystals and Their Bioimaging Applications by Yu, Kui, Ng, Peter, Ouyang, Jianying, Zaman, Md. Badruz, Abulrob, Abedelnasser, Baral, Toya Nath, Fatehi, Dorothy, Jakubek, Zygmunt J, Kingston, David, Wu, Xiaohua, Liu, Xiangyang, Hebert, Charlie, Leek, Donald M, Whitfield, Dennis M

“…We report our newly developed low-temperature synthesis of colloidal photoluminescent (PL) CuInS2 nanocrystals (NCs) and their in vitro and in vivo imaging…”
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Total Biosynthesis of Legionaminic Acid, a Bacterial Sialic Acid Analogue by Hassan, Mohamed I., Lundgren, Benjamin R., Chaumun, Michael, Whitfield, Dennis M., Clark, Brady, Schoenhofen, Ian C., Boddy, Christopher N.

“…Legionaminic acid, Leg5,7Ac2, a nonulosonic acid like 5‐acetamido neuraminic acid (Neu5Ac, sialic acid), is found in cell surface glycoconjugates of bacteria…”
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Acyl Transfer as a Problematic Side Reaction in Polymer-Supported Oligosaccharide Synthesis by Nukada, Tomoo, Berces, Attila, Whitfield, Dennis M

“…Under a wide variety of glycosylation conditions acyl transfer to the polymer support competed with glycoside formation, including the pivaloyl protecting…”
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A short route to l-iduronic acid building blocks for the syntheses of heparin-like disaccharides by Ke, Weijun, Whitfield, Dennis M, Gill, Manjinder, Larocque, Suzon, Yu, Siu-Hong

“…The effective preparation of differentially protected l-iduronic acid derivatives, as building blocks for the synthesis of heparin-like oligosaccharides, is…”
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Identification of Labile UDP-Ketosugars in Helicobacter pylori, Campylobacter jejuni and Pseudomonas aeruginosa: Key Metabolites used to make Glycan Virulence Factors by McNally, David J., Schoenhofen, Ian C., Mulrooney, Erin F., Whitfield, Dennis M., Vinogradov, Evgeny, Lam, Joseph S., Logan, Susan M., Brisson, Jean-Robert

“…UDP‐hexos‐4‐ulose sugars occupy a central role in the biosynthesis of lipopolysaccharides, capsular polysaccharides, and antibiotics in bacteria. Little is…”
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The Conformational Origin of the Barrier to the Formation of Neighboring Group Assistance in Glycosylation Reactions:  A Dynamical Density Functional Theory Study by Bérces, Attila, Enright, Gary, Nukada, Tomoo, Whitfield, Dennis M

“…Static and dynamical Density Functional Theory studies of 2,6-di-O-acetyl-3,4-O-isopropylidene-d-galactopyranosyl cation have shown that this cation can exist…”
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CMP-Pseudaminic Acid is a Natural Potent Inhibitor of PseB, the First Enzyme of the Pseudaminic Acid Pathway in Campylobacter jejuni and Helicobacter pylori by McNally, David J., Schoenhofen, Ian C., Houliston, R. Scott, Khieu, Nam H., Whitfield, Dennis M., Logan, Susan M., Jarrell, Harold C., Brisson, Jean-Robert

“…Deadly decorations. Campylobacter jejuni and Helicobacter pylori decorate their flagella, which are essential for virulence, with pseudaminic acid (Pse). Pse…”
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CMP-legionaminic acid pathway in Campylobacter: Biosynthesis involving novel GDP-linked precursors by Schoenhofen, Ian C, Vinogradov, Evgeny, Whitfield, Dennis M, Brisson, Jean-Robert, Logan, Susan M

“…The sialic acid-like sugar 5,7-diacetamido-3,5,7,9-tetradeoxy-D-glycero-D-galacto-nonulosonic acid, or legion- aminic acid, is found as a virulence-associated…”
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