- Fluorinated Carbohydrates as Lectin Ligands: Simultaneous Screening of a Monosaccharide Library and Chemical Mapping by 19F NMR Spectroscopy
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Molecular recognition of carbohydrates is a key step in essential biological processes. Carbohydrate receptors can distinguish monosaccharides even if they only differ in a single aspect of the orientation of the hydroxyl groups or harbor subtle chemical
- Martínez, J. Daniel,Manzano, Ana I.,Calvi?o, Eva,Diego, Ana De,Rodriguez De Francisco, Borja,Romanò, Cecilia,Oscarson, Stefan,Millet, Oscar,Gabius, Hans-Joachim,Jiménez-Barbero, Jesús,Ca?ada, Francisco J.
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p. 16072 - 16081
(2020/12/22)
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- Anomeric Selectivity of Trehalose Transferase with Rare l -Sugars
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Retaining LeLoir glycosyltransferases catalyze the formation of glycosidic bonds between nucleotide sugar donors and carbohydrate acceptors. The anomeric selectivity of trehalose transferase from Thermoproteus uzoniensis was investigated for both d- and l-glycopyranose acceptors. The enzyme couples a wide range of carbohydrates, yielding trehalose analogues with conversion and enantioselectivity of >98%. The anomeric selectivity inverts from α,α-(1 → 1)-glycosidic bonds for d-glycopyranose acceptors to α,β-(1 → 1)-glycosidic bonds for l-glycopyranose acceptors, while (S)-selectivity was retained for both types of sugar acceptors. Comparison of protein crystal structures of trehalose transferase in complex with α,α-trehalose and an unnatural α,β-trehalose analogue highlighted the mechanistic rationale for the observed inversion of anomeric selectivity.
- Bento, Isabel,Hagedoorn, Peter-Leon,Hanefeld, Ulf,Jeffries, Cy M.,Laustsen, Jesper U.,Marsden, Stefan R.,Mestrom, Luuk,Svergun, Dmitri I.,Van Der Eijk, Hessel
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p. 8835 - 8839
(2020/09/18)
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- Synthesis method and application of sialylated TF antigen and its fluorination derivatives
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The invention discloses a synthesis method and an application of a sialylated TF antigen and its fluorination derivatives. The method includes the following steps: (1) chemically synthesizing fluorogalactose and fluorogalactosamine analogues; (2) chemically synthesizing a fluorinated TF antigen; and (3) synthesizing the sialylated TF antigen and its fluorination derivatives through an enzyme technology. The flexibility of a chemical synthesis technology is combined with the high regioselectivity and the high efficiency of the enzyme synthesis technology, so the enzymatic synthesis of the fluorosialylated TF antigen is achieved for the first time, and the disadvantages of many synthesis steps, poor stereoselectivity, low yield and use of a heavy metal salt in existing chemical synthesis ofthe fluorosialylated TF antigen are overcome. A fluorotumor-associated carbohydrate antigen has a higher stability than natural carbohydrate antigen, so the sialylated TF antigen and its fluorinationderivatives have a broad application prospect in the development of novel antitumor vaccines.
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- Fluorinated glycosyl amino acids for mucin-like glycopeptide antigen analogues
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The aberrant glycosylation profiles of mucin glycoproteins on epithelial tumour cells represent attractive target structures for the development of immunotherapy against cancer. Mucin-type glycopeptides have been successfully investigated as molecularly defined vaccine prototypes for triggering humoral immunity but are susceptible to rapid in vivo degradation. As a potential means to enhance the bioavailabilities of the antigenic structures, hydrolysis-resistant carbohydrate analogues with fluorine substituents at positions C6, C2′ and C6′ were synthesised and incorporated into the tandem repeat sequence of the mucin MUC1. The resulting pseudo-glycopeptides can be used to elucidate the effects of chemically modified antibody determinants on metabolic and immunological properties.
- Wagner, Sarah,Mersch, Christian,Hoffmann-Roeder, Anja
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supporting information; experimental part
p. 7319 - 7330
(2010/09/16)
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- Synthesis of (6-2H)- and 6-deoxy-6-fluoro-L-galactose derivatives
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The selective oxidation of trimethylsilylated D-galactose diethyl dithioacetal using Collins reagent provided the corresponding D-galacto-hexodialdo dithioacetal. Successive acid hydrolysis, isopropylidenation, and cleavage of the dithioacetal group gave the 1,2;3,4-di-O-isopropylidene-L-galacto-hexodialdo-1,5-pyranose as a key intermediate for the synthesis of 6-fluoro- and 6-deutero-substituted L-fucose derivatives.
- Brackhagen, Meinolf,Boye, Hanna,Vogel, Christian
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- Chemo-enzymatic synthesis of fluorinated sugar nucleotide: Useful mechanistic Probes for glycosyltransferases
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An effective procedure for the synthesis of 2-deoxy-2-fluoro-sugar nucleotides via Selectfluor-mediated electrophilic fluorination of glycals with concurrent nucleophilic addition or chemo-enzymatic transformation has been developed, and the fluorinated sugar nucleotides have been used as probes for glycosyltransferases, including fucosyltransferase III, V, VI, and VII, and sialyl transferases. In general, these fluorinated sugar nucleotides act as competitive inhibitors versus sugar nucleotide substrates and form a tight complex with the glycosyltransferase. Copyright (C) 2000 Elsevier Science Ltd.
- Burkart, Michael D.,Vincent, Stephane P.,Dueffels, Arno,Murray, Brion W.,Ley, Steven V.,Wong, Chi-Huey
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p. 1937 - 1946
(2007/10/03)
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- UDP-6-deoxy-6-fluoro-α-D-galactose binds to two different galactosyltransferases, but neither can effectively catalyze transfer of the modified galactose to the appropriate acceptor
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The effect of substitution of the HO-6 of D-galactose with fluorine on the ability of α-(1→3)-galactosyltransferase (EC 2.4.1.151) and β-(1→4)-galactosyltransferase (EC 2.4.1.22) to catalyze its transfer from UDP to an appropriate acceptor was determined. HPLC analyses indicated that each transferase properly catalyzed formation of the expected product [β-D-Gal-(1→4)-D-GlcNAc] for the β-(1→4)-galactosyltransferase and α-D-Gal-(1→3)-β-D-Gal-(1→4)-D-GlcNAc for the α-(1→3)-D-galactosyltransferase] when UDP-α-D-Gal was the substrate. When UDP-6-deoxy-6-fluoro-α-D-galactose (6) was used in conjunction with each transferase, no product indicative of transfer of 6-deoxy-6-fluoro-D-galactose to its respective acceptor sugar was identified. 6-Deoxy-6-fluoro-D-galactose (3) was obtained by hydrolysis of methyl 6-deoxy-6-fluoro-α-D-galactopyranoside, synthesized by the selective fluorination of methyl α-D-galactopyranoside with diethylaminosulfur trifluoride (DAST), with aqueous trifluoroacetic acid. Acetylation of 3 gave crystalline 1,2,3,4-tetra-O-acetyl-6-deoxy-6-fluoro-β-D-galactopyranose, which was converted to the corresponding 1-α-phosphate and used for the synthesis of 6. Copyright (C) 1999 Elsevier Science Ltd.
- Schengrund, Cara-Lynne,Kovac, Pavol
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- Recognition of synthesis deoxy and deoxyfluoro analogs of the acceptor α-L-Fucp-(1 → 2)-B-D-Galp-OR by the blood-group A and B gene-specified glycosyltransferases
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The disaccharide α-L-Fuc p-(1→2)-B-D-Gal p-O-(CH2 )7CH3(6), is an acceptor for both glycosyl-transferases responsible for the biosynthesis of the A and B blood-group antigens. These enzymes transfer GalNAc and Gal, respect
- Lowary,Hindsgaul
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p. 163 - 195
(2007/10/02)
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- THE SYNTHESIS AND HYDROLYSIS OF A SERIES OF DEOXYFLUORO-D-GLUCOPYRANOSYL PHOSPHATES
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The synthesis of all four deoxyfluoro-α-D-glucopyranosyl phosphates is described.Rate conctants for their acid-catalyzed hydrolysis were determined, and fluorine substitution was shown to have a significant effect in lowering the rate, particularly when t
- Withers, Stephen G.,MacLennan, David J.,Street, Ian P.
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p. 127 - 144
(2007/10/02)
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- Halogenated L-Fucose and D-Galactose Analogues: Synthesis and Metabolic Effects
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Several new analogues of L-fucose modified in the 2-position and the 5-methyl group have been synthesized as potential plasma-membrane glycoconjugate inhibitors or modifiers, and their biological effects have been studied. 2-Chloro-, 2-bromo-, and 2-iodo-2-deoxy-L-fucose (9a, 9b, and 13, respectively) have been prepared by addition of the appropriate halogen to 3,4-di-O-acetyl-L-fucal, followed by hydrolysis of the anomeric halogen and the acetyl groups.A series of four halogenated 5-methyl analogues of L-fucose (4, X = F, Cl, Br and I) have been obtained starting from1,2:3,4-di-O-isopropylidene-L-galactose.The synthesis of this latter compound has been improved.A corresponding series of 6-deoxy-6-halo-D-galactose analogues, which are enantiomers of the 5-(halomethyl)-L-fucose analogues, has also been synthesized.Analogues 4b, 4c, and 9b at 1*10-3 M specifically inhibited the incorporation of L-fucose into macromolecular components of SW613 human mammary tumor cells.Analogue 13 inhibited the growth of L1210 murine leukemic cells with an IC50 of 6*10-5 M in culture. 6-Deoxy-6-fluoro-D-galactose and its enantiomer 4a were found to be effective inhibitors of D-galactose and L-fucose incorporation, respectively, into macromolecular components of human mammary tumor cells.The efectiveness of inhibition was reduced with an increase in size of the halogen atom.Analogue 4a and its enantiomer have been tritiated at C-1 and both were found to be activated to a nucleotide sugar, which was followed by incorporation into the macromolecular fraction of SW613 human mammary tumor cells in vitro.
- Sufrin, Janice R.,Bernacki, Ralph J.,Morin, Michael J.,Korytnyk, Walter
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p. 143 - 149
(2007/10/02)
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