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    9981 results match your criteria Carbohydrate research[Journal]

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    Isolation and characterisation of an unexpected byproduct in the regioselective butane diacetal protection of α-methyl galactopyranoside.
    Carbohydr Res 2017 Nov 6;455:14-17. Epub 2017 Nov 6.
    Chemistry, University of Southampton, Highfield, Southampton, SO17 1BJ, UK. Electronic address:
    The regioselective protection of both methyl galactopyranoside anomers at the 2 and 3-positions as the butane diacetal (BDA) is well known. Here we describe the formation of an unexpected byproduct, which mainly occurs when α-methyl galactopyranoside is reacted with 2,3-butanedione under BF3•OEt2 catalysis. The structure of the byproduct, which did not arise from anomerisation to the β-anomer or from BDA formation at the galactopyranoside 3,4-positions, was elucidated by NMR and X-ray crystallographic analysis, and proved to be the expected BDA protected galactopyranoside, but in which the stereochemistry of both its BDA acetal centres are inverted. Read More

    Tandem mass spectrometry of fucoidan-derived fragments, labeled with heavy-oxygen.
    Carbohydr Res 2017 Nov 4;455:10-13. Epub 2017 Nov 4.
    G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Sciences, Stoletiya Vladivostoka Prosp. 159/2, 690022 Vladivostok, Russian Federation.
    A procedure for the partial depolymerization of sulfated fucans and selective labeling with (18)O was developed. A tandem electrospray ionization mass spectrometry (ESI MS/MS) was applied for the direct analysis of mixtures of structurally-different oligosaccharides, derived from the fucoidans of known structure. The presence of label allowed unambiguous distinguishing between the fragment ions of (0,2)X0-type at m/z 287 and (2,4)A-type at m/z 285, since (18)O at the reducing end gave +2 mass shifting. Read More

    Concise synthesis of 2,7-anhydrosialic acid derivatives and its application.
    Carbohydr Res 2017 Oct 19;453-454:44-53. Epub 2017 Oct 19.
    Institute of Chemistry, Academia Sinica, Taipei 115, Taiwan; Taiwan International Graduate Program (TIGP), Sustainable Chemical Science and Technology (SCST), Academia Sinica, Taipei 115, Taiwan. Electronic address:
    In N-acetylneuraminic acid, apart from O9 and O8, a possible glycosylation site is the O4 position. For example, gangliosides HLG-2 and HPG-7 are considered to be potential lead compounds for carbohydrate-based drug development to treat neural disorders. However, the construction of their α(1 → 4) fucosyl sialic acid and α(2 → 4) linkages between sialic acids is difficult because of the regioselectivity problem. Read More

    Effect of sucralose on the enzyme kinetics of invertase using real-time NMR spectroscopy and progress curve analysis.
    Carbohydr Res 2017 Oct 31;455:5-9. Epub 2017 Oct 31.
    Department of Chemistry, California State University, Fresno CA 93740, United States; Department of Pathology and Laboratory Medicine, School of Medicine, University of California, Davis CA 95616, United States. Electronic address:
    Sucralose, a derivative of sucrose, is widely used in noncaloric artificial sweeteners (NAS). Contrary to the belief that sucralose is physiologically inert and a healthy alternative sweetener to natural sugar, emerging studies indicate that sucralose alters the host metabolism as well as the composition of the microbiome. In this manuscript, we use real-time nuclear magnetic resonance (NMR) spectroscopy to demonstrate that sucralose alters the enzymatic conversion of sucrose to glucose and fructose. Read More

    Supramolecular glycorhodamine-polymer dot ensembles for the homogeneous, fluorogenic analysis of lectins.
    Carbohydr Res 2017 Nov 1;455:1-4. Epub 2017 Nov 1.
    Key Laboratory for Advanced Materials & Feringa Nobel Prize Scientist Joint Research Center, School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Meilong Rd., Shanghai 200237, China. Electronic address:
    We have developed a new series of glycoprobe-polymer dot ensembles for the fluorogenic, homogeneous detection of lectins. Electrostatic self-assembly between positively charged rhodamine-based glycosides and negatively charged poly(3-hexylthiophene-2,5-diyl)/poly(styrene-co-maleic anhydride) polymer dots produces the ensembles with a quenched fluorescence. Fluorescence spectroscopy showed that the ensembles exhibited a concentration-dependent fluorescence enhancement with selective lectins over a range of unselective lectins and proteins. Read More

    Mannosylcalix[n]arenes as multivalent ligands for DC-SIGN.
    Carbohydr Res 2017 Oct 31;453-454:36-43. Epub 2017 Oct 31.
    Dipartimento di Scienze Chimiche, della Vita e della Sostenibilità Ambientale, Università di Parma, Parco Area delle Scienze 17/A, 43124 Parma, Italy. Electronic address:
    DC-SIGN is a receptor protruded from the membrane of immature dendritic cells (DCs) that participates in the activation of the immune response through the recognition of pathogen-associated molecular patterns (PAMPs). On the other hand, HIV exploits the interaction between high-mannose structures of its envelope glycoprotein gp120 and DC-SIGN to be transported towards and infect T-cells. DC-SIGN is involved in the recognition process in the form of a tetramer and the multiple exposition of carbohydrate recognition sites (CRSs) is amplified by the formation on the DCs membrane of patches of tetramers. Read More

    Properties of two fungal endo-β-1,3-galactanases and their synergistic action with an exo-β-1,3-galactanase in degrading arabinogalactan-proteins.
    Carbohydr Res 2017 Oct 25;453-454:26-35. Epub 2017 Oct 25.
    Division of Life Science, Graduate School of Science and Engineering, Saitama University, 255 Shimo-okubo, Sakura-ku, Saitama 338-8570, Japan; Institute for Environmental Science and Technology, Saitama University, 255 Shimo-okubo, Sakura-ku, Saitama 338-8570, Japan. Electronic address:
    Arabinogalactan-proteins (AGPs) are plant proteoglycans, which are widely encountered in the plant kingdom, usually localized on the cell surface. The carbohydrate moieties of AGPs consist of β-1,3-galactan main chains and β-1,6-galactan side chains, to which other auxiliary sugars are attached. To date, FvEn3GAL isolated from Flammulina velutipes is the sole β-1,3-galactanase acting on β-1,3-galactan in an endo-manner. Read More

    Synthesis of P(1)-(11-phenoxyundecyl)-P(2)-(2-acetamido-2-deoxy-3-O-α-D-rhamnopyranosyl-α-D-glucopyranosyl) diphosphate and P(1)-(11-phenoxyundecyl)-P(2)-(2-acetamido-2-deoxy-3-O-β-D-galactopyranosyl-α-D-galactopyranosyl) diphosphate for the investigation of biosynthesis of O-antigenic polysaccharides in Pseudomonas aeruginosa and Escherichia coli O104.
    Carbohydr Res 2017 Nov 3;453-454:19-25. Epub 2017 Nov 3.
    Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Canada.
    Two new phenoxyundecyl diphosphate sugars were synthesized for the first time: P(1)-(11-phenoxyundecyl)-P(2)- (2-acetamido-2-deoxy-3-O-α-D-rhamnopyranosyl-α-D-glucopyranosyl) diphosphate and P(1)-(11-phenoxyundecyl)-P(2)-(2-acetamido-2-deoxy-3-O-β-D-galactopyranosyl-α-D-galactopyranosyl) diphosphate to study the third step of biosynthesis of the repeating units of O-antigenic polysaccharides in Pseudomonas aeruginosa and E.coli O104 respectively. Read More

    Synthesis of substrate analogues as potential inhibitors for Mycobacterium tuberculosis enzyme MshC.
    Carbohydr Res 2017 Nov 3;453-454:10-18. Epub 2017 Nov 3.
    Department of Chemistry and Biochemistry and School of Green Chemistry and Engineering, The University of Toledo, 2801 W. Bancroft Street, Toledo, Ohio 43606, United States. Electronic address:
    Mycothiol cysteine ligase (MshC) is a key enzyme in the mycothiol (MSH) biosynthesis and a promising target for developing new anti-mycobacterial compounds. Herein, we report on the synthesis of substrate analogues, as potential inhibitors, for the MshC enzyme. The target molecules were synthesized employing a Schmidt glycosylation strategy using an enantiomerically pure inositol acceptor and 2-deoxy trichloroacetimidate glycosyl donors with glycosylation yields greater than 70% and overall yields >5%. Read More

    Overview on the antiviral activities and mechanisms of marine polysaccharides from seaweeds.
    Carbohydr Res 2017 Oct 31;453-454:1-9. Epub 2017 Oct 31.
    Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Lihu Avenue1800, Wuxi 214122, China. Electronic address:
    Marine polysaccharides are attracting increasing attention in medical and pharmaceutical development because of their important biological properties. The seaweed polysaccharides have now become a rich resource of potential antiviral drugs due to their antiviral activities against various viruses. The structural diversity and complexity of marine polysaccharides and their derivatives contribute to their antiviral activities in different phases of many different viral infection processes. Read More

    Monitoring of reactions catalyzed by lytic polysaccharide monooxygenases using highly-sensitive fluorimetric assay of the oxygen consumption rate.
    Carbohydr Res 2017 Nov 24;452:156-161. Epub 2017 Oct 24.
    Department of Chemistry, M. V. Lomonosov Moscow State University, Vorobyovy Gory 1/11, Moscow 119991, Russia; Federal Research Centre "Fundamentals of Biotechnology", Russian Academy of Sciences, Leninsky Pr. 33, Moscow 119071, Russia.
    Lytic polysaccharide monooxygenases (LPMOs) are recently discovered enzymes that catalyze the oxidative deconstruction of polysaccharides. However fast and reliable methods of determination of LPMO activity still need to be developed, especially those based on the initial reaction rates. A method based on the oxygen consumption rate (OCR) measurements, using a Seahorse XFp Analyzer with highly-sensitive fluorimetric sensors, was applied for monitoring the oxidation of amorphous cellulose by three fungal LPMOs: recombinant enzymes from Thielavia terrestris (GH61E), Trichoderma reesei (Cel61A), and a native LPMO9A from Myceliophthora thermophila. Read More

    Acinetobacter baumannii K13 and K73 capsular polysaccharides differ only in K-unit side branches of novel non-2-ulosonic acids: di-N-acetylated forms of either acinetaminic acid or 8-epiacinetaminic acid.
    Carbohydr Res 2017 Nov 19;452:149-155. Epub 2017 Oct 19.
    N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia.
    Structures of capsular polysaccharides of Acinetobacter baumannii isolates carrying KL13 and KL73 gene clusters were established. The closely related KL73 and KL13 gene clusters differ only by one gene in the module responsible for synthesis of the non-2-ulosonic acids. The K13 and K73 polysaccharides differ only in a single side-chain sugar, which is either 5,7-diacetamido-3,5,7,9-tetradeoxy-l-glycero-l-altro- or -d-glycero-l-altro-non-2-ulosonic acid [di-N-acetylated forms of acinetaminic acid (Aci5Ac7Ac) or 8-epiacinetaminic acid (8eAci5Ac7Ac), respectively]. Read More

    Synthesis of a biotinylated keratan sulfate tetrasaccharide composed of dimeric Galβ1-4GlcNAc6Sβ.
    Carbohydr Res 2017 Nov 18;452:97-107. Epub 2017 Sep 18.
    Department of Regional Environment, Faculty of Regional Sciences, Tottori University, Tottori 680-8551, Japan; Department of Life and Environmental Agricultural Sciences, Faculty of Agriculture, Tottori University, Tottori 680-8553, Japan. Electronic address:
    We successfully synthesized the biotinylated keratan sulfate tetrasaccharide, Galβ1-4GlcNAc6Sβ1-3Galβ1-4GlcNAc6Sβ in a stereocontrolled manner. The suitably protected Galβ1-4GlcNPhth unit was converted to the corresponding donor and acceptor. Optimization in 2 + 2 coupling using AgOTf, CuBr2, and n-Bu4NBr in CH3NO2 at a low temperature afforded the desired tetrasaccharide that suppressed glycal formation. Read More

    Boronic acid-based chemical sensors for saccharides.
    Carbohydr Res 2017 Nov 20;452:129-148. Epub 2017 Oct 20.
    College of Chemistry, Beijing Normal University, Beijing 100875, China. Electronic address:
    During the past decades, the interaction between boronic acids-functionalized sensors and saccharides is of great interest in the frontier domain of the interdiscipline concerning both biology and chemistry. Various boronic acid-based sensing systems have been developed to detect saccharides and corresponding derivatives in vitro as well as in vivo, which embrace unimolecular sensors, two-component sensing ensembles, functional assemblies, and boronic acid-loaded nanomaterials or surfaces. New sensing strategies emerge in endlessly with excellent selectivity and sensitivity. Read More

    Improved isolation and characterization procedure of sialylglycopeptide from egg yolk powder.
    Carbohydr Res 2017 Nov 12;452:122-128. Epub 2017 Oct 12.
    Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA; Department of Chemistry, University of Georgia, Athens, GA 30602, USA; Chemical Biology and Drug Discovery, Utrecht University, 3584 CG Utrecht, The Netherlands; Utrecht Institute for Pharmaceutical Sciences, Utrecht University, 3584 CG Utrecht, The Netherlands; Bijvoet Center for Biomolecular Research, Utrecht University, 3584 CH Utrecht, The Netherlands. Electronic address:
    Sialylglycopeptide (SGP) is a complex bi-antennary N-glycan bearing a short peptide fragment that can be isolated from the yolk of hen eggs. This natural product has gained popularity as a starting material for the semi-synthesis of N-glycans. We have found that current isolation methods provide a glycopeptide contaminated with several related structures, one being a glycopeptide having a hexose directly attached to peptide backbone, most like through the hydroxyl containing side chain of the threonine moiety. Read More

    Regioselective glycosylation of novobiocin alters activity.
    Carbohydr Res 2017 Nov 22;452:116-121. Epub 2017 Oct 22.
    The School of Pharmacy, University College London, 29/39 Brunswick Square, London WC1N 1AX, UK. Electronic address:
    Glycosylation is a promising approach to overcome antimicrobial drug resistance. In this study, we investigated Koenigs-Knorr and phase transfer glycosylation on novobiocin. While the former only gave a 4'-OH product, the later produced mainly a kinetic controlled 5-OH product, but still achieved the 4'-OH modification and novoise-glycosylated products (with stronger base), as well as a diglycosylated compound. Read More

    Recent advances in the synthesis of rare sugars using DHAP-dependent aldolases.
    Carbohydr Res 2017 Nov 18;452:108-115. Epub 2017 Oct 18.
    Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China. Electronic address:
    The occurrence rates of non-communicable diseases like obesity, diabetes and hyperlipidemia have increased remarkably due to excessive consumption of a high-energy diet. Rare sugars therefore have become increasingly attractive owing to their unique nutritional properties. In the past two decades, various rare sugars have been successfully prepared guided by the "Izumoring strategy". Read More

    Base-modified GDP-mannose derivatives and their substrate activity towards a yeast mannosyltransferase.
    Carbohydr Res 2017 Nov 21;452:91-96. Epub 2017 Sep 21.
    School of Pharmacy, University of East Anglia, Norwich, UK; King's College London, Department of Chemistry, Faculty of Natural & Mathematical Sciences, Britannia House, 7 Trinity Street, London, SE1 1DB, UK. Electronic address:
    We have previously developed a new class of inhibitors and chemical probes for glycosyltransferases through base-modification of the sugar-nucleotide donor. The key feature of these donor analogues is the presence of an additional substituent at the nucleobase. To date, the application of this general concept has been limited to UDP-sugars and UDP-sugar-dependent glycosyltransferases. Read More

    NKT-cell glycolipid agonist as adjuvant in synthetic vaccine.
    Carbohydr Res 2017 Nov 17;452:78-90. Epub 2017 Oct 17.
    Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Hubei International Scientific and Technological Cooperation Base of Pesticide and Green Synthesis, College of Chemistry, Central China Normal University, Wuhan, Hubei 430079, PR China. Electronic address:
    NKT cells are CD1d-restricted, glycolipid antigen-reactive, immunoregulatory T lymphocytes that can serve as a bridge between the innate and adaptive immunities. NKT cells have a wide range of therapeutic application in autoimmunity, transplant biology, infectious disease, cancer, and vaccinology. Rather than triggering "danger signal" and eliciting an innate immune response, αGalCer-based NKT-cell agonist act via a unique mechanism, recruiting NKT cells which play a T helper-like role even without peptide as Th epitope. Read More

    Novel 1,2-cis-stereoselective glycosylations utilizing organoboron reagents and their application to natural products and complex oligosaccharide synthesis.
    Carbohydr Res 2017 Nov 12;452:64-77. Epub 2017 Oct 12.
    Department of Applied Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan.
    In this mini-review article, 1,2-cis-stereoselective glycosylation methods utilizing organoboron reagents and 1,2-anhydroglycosyl donors that were developed in our laboratory, including regio- and 1,2-cis-stereoselective glycosylations using glycosyl-acceptor-derived boronic ester catalysts and 1,2-cis-stereoselective glycosylations using glycosyl-acceptor-derived borinic ester catalysts, are recounted. Representative applications of these methods to the synthesis of biologically active natural products and a complex oligosaccharide are also described. Read More

    Highly efficient synthesis of bioactive oleanane-type saponins.
    Carbohydr Res 2017 Nov 23;452:43-46. Epub 2017 Aug 23.
    The National Research Centre for Carbohydrate Synthesis, Jiangxi Normal University, 99 Ziyang Avenue, Nanchang, 330022, China. Electronic address:
    Leveraging on Schmidt glycosylation method, a highly efficient approach to obtain oleanane-type triterpene saponins was fixed, whereby oleanyl mono-, disaccharide (guaianin N), trisaccharide (elatoside E), as well as tetrasaccharide (elatoside F) were obtained efficiently. The synthetic investigation has resulted in the discovery of the effect of branch-sugar incorporation sequence on the overall synthetic efficiency. Moreover, through bioactivity investigation, the cytotoxic activity of the obtained triterpenoid saponins was evaluated, and the preliminary structure-activity relationship was deduced. Read More

    Characterization of structural motifs for interactions between glycosaminoglycans and proteins.
    Carbohydr Res 2017 Nov 17;452:54-63. Epub 2017 Oct 17.
    National Glycoengineering Research Center, Shandong University, Jinan 250100, China. Electronic address:
    Glycosaminoglycans (GAGs) are a family of linear and anionic polysaccharides that play essential roles in many biological and physiological processes. Interactions between GAGs and proteins regulate function in many proteins and are related to many human diseases and disorders. The structural motifs and mechanisms for interactions between GAGs and proteins are not fully understood. Read More

    Synthesis of Lewis(X)-O-Core-1 threonine: A building block for O-linked Lewis(X) glycopeptides.
    Carbohydr Res 2017 Nov 10;452:47-53. Epub 2017 Oct 10.
    Department of Surgery, Center for Drug Discovery and Translational Research, Beth Israel Deaconess Medical Center, Harvard Medical School, 110 Francis Street, Suite 9F, Boston, MA 02215, USA; Wyss Institute of Biologically Inspired Engineering, Harvard University, 110 Francis Street, Suite 9F, Boston, MA 02115, USA; Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA 02139, USA. Electronic address:
    Lewis(X) (Le(X)) is a branched trisaccharide Galβ1→4(Fucα1→3)GlcNAc that is expressed on many cell surface glycoproteins and plays critical roles in innate and adaptive immune responses. However, efficient synthesis of glycopeptides bearing Le(X) remains a major limitation for structure-function studies of the Le(X) determinant. Here we report a total synthesis of a Le(X) pentasaccharide 1 using a regioselective 1-benzenesulfinyl piperidine/triflic anhydride promoted [3 + 2] glycosylation. Read More

    Synthesis and binding affinity analysis of α1-2- and α1-6-O/S-linked dimannosides for the elucidation of sulfur in glycosidic bonds using quartz crystal microbalance sensors.
    Carbohydr Res 2017 Nov 9;452:35-42. Epub 2017 Oct 9.
    KTH - Royal Institute of Technology, Department of Chemistry, Teknikringen 36, S-10044 Stockholm, Sweden; Department of Chemistry, University of Massachusetts Lowell, 1 University Ave., MA, 01854 Lowell, USA. Electronic address:
    The role of sulfur in glycosidic bonds has been evaluated using quartz crystal microbalance methodology. Synthetic routes towards α1-2- and α1-6-linked dimannosides with S- or O-glycosidic bonds have been developed, and the recognition properties assessed in competition binding assays with the cognate lectin concanavalin A. Mannose-presenting QCM sensors were produced using photoinitiated, nitrene-mediated immobilization methods, and the subsequent binding study was performed in an automated flow-through instrumentation, and correlated with data from isothermal titration calorimetry. Read More

    Chemical remodeling cell surface glycans for immunotargeting of tumor cells.
    Carbohydr Res 2017 Nov 10;452:25-34. Epub 2017 Oct 10.
    Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China. Electronic address:
    Recruitment of human endogenous antibodies to target and eliminate tumor cells is a promising therapeutic strategy in the biomedical field. Current antibody-recruiting molecules are typically bi-functional agents that utilize cell-surface receptor binding property for targeting. This approach has intrinsic limitations due to the heterogeneity of tumor cells and the limited number of receptors on the cell surface. Read More

    Structural characterisation of the capsular polysaccharide expressed by Burkholderia thailandensis strain E555:: wbiI (pKnock-KmR) and assessment of the significance of the 2-O-acetyl group in immune protection.
    Carbohydr Res 2017 Nov 21;452:17-24. Epub 2017 Sep 21.
    Chemical, Biological and Radiological Division, Defence Science and Technology Laboratory, Porton Down, Salisbury, Wiltshire, SP4 0JQ, UK; University of Exeter, Stocker Road, Exeter, EX4 4QD, UK; London School of Hygiene and Tropical Medicine, Keppler Street, London, WC1 7HT, UK.
    Burkholderia pseudomallei and its close relative B. mallei are human pathogens that are classified as Tier 1 bio-threat agents. Both organisms have previously been shown to constitutively produce a capsular polysaccharide (CPS) that is both a virulence determinant and protective antigen. Read More

    (1)H NMR studies of molecular interaction of D-glucosamine and N-acetyl-D-glucosamine with capsaicin in aqueous and non-aqueous media.
    Carbohydr Res 2017 Nov 29;452:6-16. Epub 2017 Sep 29.
    Departamento de Investigación en Polímeros y Materiales, Universidad de Sonora, Hermosillo, Sonora 83000, México.
    Complex formation of D-glucosamine (Gl) and N-acetyl-D-glucosamine (AGl) with capsaicin (Cp) were studied by (1)H NMR titrations in H2O-d2 and DMSO-d6; capsaicin is the major bioactive component of chili peppers. Every titration curve has been interpreted by formulating a suitable model for the reaction equilibrium, to elucidate intermolecular interactions. In DMSO, glucosamine cations associate with each other to yield linear aggregates, and undergo pseudo-1:1-complexation with capsaicin, the formation constant being ca. Read More

    Tracking the leaving group in the remote activation of O-2-[(propan-2-yl)sulfinyl]benzyl (OPSB) glycoside.
    Carbohydr Res 2017 Nov 28;452:1-5. Epub 2017 Sep 28.
    Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, Hubei, 430030, China; Institute of Brain Research, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan, Hubei, 430030, China. Electronic address:
    In our recently developed interrupted Pummerer reaction mediated glycosylation with O-2-[(propan-2-yl)sulfinyl]benzyl (OPSB) glycosides as glycosyl donors, the anomeric leaving group was recovered as a benzyl alcohol which didn't affect the glycosylation efficiency. To investigate the mechanism of the occurrence of this alcohol, an (18)O isotopic labeling reaction was carried out to track the leaving group. It was found that the benzyl alcohol was generated during the aqueous work up process from an inactive cyclic oxo-sulfonium ion intermediate. Read More

    Synthesis and gelation property of a series of disaccharide triazole derivatives.
    Carbohydr Res 2017 Nov 15;451:81-94. Epub 2017 Sep 15.
    Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, VA 23529, USA. Electronic address:
    Low molecular weight gelators are important for the study of supramolecular chemistry and have useful applications for biomaterials. Glycomimetics that are easily accessible and have useful gelation properties are especially interesting molecules. In this research, nine per-O-acetyl lactosyl- and thirteen per-O-acetyl maltosyl triazole derivatives were synthesized and analyzed. Read More

    Preparation of new β-D-xyloside- and β-D-xylobioside-based ionic liquids through chemical and/or enzymatic reactions.
    Carbohydr Res 2017 Nov 23;451:72-80. Epub 2017 Sep 23.
    Institut de Chimie Moléculaire de Reims, CNRS UMR 7312, Université de Reims Champagne-Ardenne, BP 1039, 51687 Reims Cedex, France. Electronic address:
    Several tetraalkylphosphonium and tetraalkylammonium salts containing xyloside- and xylobioside-based anionic moieties have been prepared. Two stereoselective routes have been developed: i) a chemical pathway in four steps from D-xylose, and ii) a chemoenzymatic pathway directly from biomass-derived xylans. These salts displayed interesting properties as ionic liquids. Read More

    The convergent synthesis and anticancer activity of broussonetinines related analogues.
    Carbohydr Res 2017 Nov 19;451:59-71. Epub 2017 Sep 19.
    Institute of Physical Chemistry and Chemical Physics, Department of Physical Chemistry, Slovak University of Technology, Radlinského 9, 812 37 Bratislava, Slovak Republic.
    The convergent synthesis of broussonetinines related congeners 3 and 4 with the simple C13 alkyl side chain and differently configured pyrrolidine skeleton has been achieved. Our approach relied on the [3,3]-sigmatropic rearrangements of chiral allylic substrates derived from d-xylose. Cross metathesis of the common oxazolidinone intermediates 7 and 8 with tridec-1-ene followed by alkylative cyclization completed the construction of both C-alkyl iminosugars. Read More

    Chemoenzymatic synthesis of Neu5Ac9NAc-containing α2-3- and α2-6-linked sialosides and their use for sialidase substrate specificity studies.
    Carbohydr Res 2017 Nov 18;451:51-58. Epub 2017 Sep 18.
    Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, CA 95616, USA. Electronic address:
    O-Acetylation of sialic acid (Sia) modulates its recognition by sialic acid-binding proteins and plays an important role in biological and pathological processes. 9-O-Acetylation is the most common modification of sialic acid in human. However, study of O-acetylated sialoglycans is hampered due to the instability of O-acetyl group towards pH changes and sensitivity to esterases. Read More

    Limitations in the description of conformational preferences of C-disaccharides: The (1 → 3)-C-mannobiose case.
    Carbohydr Res 2017 Nov 18;451:42-50. Epub 2017 Sep 18.
    Institute of Organic Chemistry and Biochemistry AS CR, Gilead Sciences & IOCB Research Center, Flemingovo nám. 2, 166 10 Prague, Czech Republic. Electronic address:
    Conformational preferences of two C-glycosyl analogues of Manp-(1 → 3)-Manp, were studied using a combined method of theoretical and experimental chemistry. Molecular dynamics was utilized to provide conformational behavior along C-glycosidic bonds of methyl 3-deoxy-3-C-[(α-d-mannopyranosyl)methyl]-α-d- and l-mannopyranosides. The OPLS2005 and Glycam06 force fields were used. Read More

    Novel teichulosonic acid and glycosyl 1-phosphate polymers from the cell walls of Arthrobacter sp., strains VKM Ac-2549 and VKM Ac-2550, phylogenetically close to Arthrobacter crystallopoietes.
    Carbohydr Res 2017 Nov 14;451:36-41. Epub 2017 Sep 14.
    All-Russian Collection of Microorganisms (VKM), G. K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russian Federation.
    Novel teichulosonic acid with the repeating unit →6)-β-D-GlcpNAc-(1→8)-α-Kdn-(2→ has been found in the cell walls of two Arthrobacter strains, VKM Ac-2549 and VKM Ac-2550. The teichulosonic acid was revealed in representatives of the genus Arthrobacter for the first time. Two other polymers identified in the above strains were poly(monoglycosyl 1-phosphate) and poly(diglycosyl 1-phosphate) of hitherto unknown structures, i. Read More

    Theoretical study on the anomeric effect in α-substituted tetrahydropyrans and piperidines.
    Carbohydr Res 2017 Nov 15;451:29-35. Epub 2017 Sep 15.
    Department of Chemistry, Federal University of Lavras, 37200-000, Lavras, MG, Brazil. Electronic address:
    Conformational effects, including some controversial examples, have been reported in this work for 2-substituted tetrahydropyrans and piperidines, and for the respective protonated compounds [substituent = F, OH, OCH3, NH2, NHCH3 and N(CH3)2]. Hyperconjugation plays a major role in most cases, either due to endo or exo-anomeric interactions, especially when nitrogen is the electron donor to an antiperiplanar σ* orbital. This interaction also seems to contribute for the Perlin and reverse fluorine Perlin-like effects, which are related to the relative magnitude of (1)JC,H and (1)JC,F coupling constants, respectively, in axial and equatorial conformers. Read More

    Stereoselective sialylation with O-trifluoroacetylated thiosialosides: hydrogen bonding involved?
    Carbohydr Res 2017 Nov 8;451:12-28. Epub 2017 Sep 8.
    N. D. Zelinsky Institute of Organic Chemistry of the Russian Academy of Sciences, Leninsky prosp., 47, 119991 Moscow, Russian Federation. Electronic address:
    A series of novel sialyl donors containing O-trifluoroacetyl (TFA) groups at various positions was synthesized. The choice of protecting groups in sialyl donors was based on hypothesis that variations in ability of different acyl groups to act as hydrogen bond acceptors would influence the supramolecular structure of reaction mixture (solution structure), hence the outcome of sialylation. These glycosyl donors were examined in the model glycosylation of the primary hydroxyl group of 1,2:3,4-di-O-isopropylidene-α-D-galactopyranose in comparison with sialyl donors without O-TFA groups. Read More

    Synthesis of a trisaccharide repeating unit of the O-antigen from Burkholderia cenocepacia and its dimer.
    Carbohydr Res 2017 Nov 8;451:1-11. Epub 2017 Sep 8.
    National Glycoengineering Research Center, Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, 27 Shanda Nan Lu, Jinan 250010, PR China. Electronic address:
    The trisaccharide repeating unit of an O-antigen derived from Burkholderia cenocepacia and its dimer, i.e., α-L-Rhap-(1 → 3)-α-D-GalpNAc-(1 → 3)-β-D-GalpNAc-O(CH2)3N3 (1) and α-L-Rhap-(1 → 3)-α-D-GalpNAc-(1 → 3)-β-D-GalpNAc-(1 → 4)-α-L-Rhap-(1 → 3)-α-D-GalpNAc-(1 → 3)-β-D-GalpNAc-O(CH2)3N3 (2), respectively, were synthesized via a highly convergent strategy. Read More

    The trehalose-specific transporter LpqY-SugABC is required for antimicrobial and anti-biofilm activity of trehalose analogues in Mycobacterium smegmatis.
    Carbohydr Res 2017 Oct 9;450:60-66. Epub 2017 Aug 9.
    Department of Chemistry and Biochemistry, Central Michigan University, Mount Pleasant, MI 48859, United States. Electronic address:
    Mycobacteria, including the bacterial pathogen that causes human tuberculosis, possess distinctive pathways for synthesizing and utilizing the non-mammalian disaccharide trehalose. Trehalose metabolism is essential for mycobacterial viability and has been linked to in vitro biofilm formation, which may bear relevance to in vivo drug tolerance. Previous research has shown that some trehalose analogues bearing modifications at the 6-position inhibit growth of various mycobacterial species. Read More

    An acceptor analogue of β-1,4-galactosyltransferase: Substrate, inhibitor, or both?
    Carbohydr Res 2017 Oct 31;450:54-59. Epub 2017 Aug 31.
    King's College London, Department of Chemistry, Faculty of Natural & Mathematical Sciences, Britannia House, 7 Trinity Street, London, SE1 1DB, UK. Electronic address:
    Many glycosyltransferase inhibitors in the literature are structurally derived from the donor or acceptor substrate of the respective enzyme. A representative example is 2-naphthyl β-d-GlcNAc, a synthetic GlcNAc glycoside that has been reported as a galactosyltransferase inhibitor. This GlcNAc derivative is attractive as a chemical tool compound for biological and biochemical studies because of its reported potency as an inhibitor, and its short and straightforward synthesis from readily available starting materials. Read More

    Synthesis of a series of new glycoclusters and the evaluation of their anti-adhesion activities.
    Carbohydr Res 2017 Oct 1;450:49-53. Epub 2017 Sep 1.
    State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Xueyuan Road, Haidian District, Beijing 100191, PR China. Electronic address:
    According to our early researches, some glycoclusters having glucose, mannose, cellose and lactose residues showed good anti-adhesion activity of leukocytes to endothelial cells and exerted anti-inflammatory effects. Based on these results and combination principles of drugs, a series of new glycoclusters modifying with potentially anti-oxidant activity pharmacophores have been synthesized, and their anti-adhesion activities were assessed by static state cell-based adhesion assay. The results showed that some modified glycoclusters displayed better activities than their leading compound. Read More

    Rational optimization of the mannoside building block for automated electrochemical assembly of the core trisaccharide of GPI anchor oligosaccharides.
    Carbohydr Res 2017 Oct 25;450:44-48. Epub 2017 Aug 25.
    Department of Chemistry and Biotechnology, Graduate School of Engineering, Tottori University, 4-101 Koyamacho-minami, Tottori City, 680-8552 Tottori, Japan; Center for Research on Green Sustainable Chemistry, Faculty of Engineering, Tottori University, Japan. Electronic address:
    We have developed a carbohydrate building block of mannosides based on DFT calculations, electrochemical analysis, and automated solution-phase synthesis. The optimized building block in hand was used to prepare the core trisaccharide of GPI anchor oligosaccharides. Read More

    Alternate synthesis to d-glycero-β-d-manno-heptose 1,7-biphosphate.
    Carbohydr Res 2017 Oct 24;450:38-43. Epub 2017 Aug 24.
    Vaccine Program, Human Health Therapeutics Portfolio, National Research Council, Ottawa, Ontario, K1A 0R6, Canada.
    d-glycero-β-d-manno-heptose 1,7-biphosphate (HBP) is an enzymatic intermediate in the biosynthesis of the heptose component of lipopolysaccharide (LPS), and was recently revealed to be a pathogen-associated molecular pattern (PAMP) that allows detection of Gram-negative bacteria by the mammalian immune system. Cellular detection of HBP depends upon its stimulation of a cascade that leads to the phosphorylation and assembly of the TRAF-interacting with forkhead-associated domain protein A (TIFA), which activates the transcription factor NF-κB. In this note, an alternate chemical synthesis of HBP is described and its biological activity is established, providing pure material for further assessing and exploiting the biological activity of this compound. Read More

    Synthesis of a model trisaccharide for studying the interplay between the anti α-Gal antibody and the trans-sialidase reactions in Trypanosoma cruzi.
    Carbohydr Res 2017 Oct 18;450:30-37. Epub 2017 Aug 18.
    Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Centro de Investigaciones en Hidratos de Carbono (CIHIDECAR), Facultad de Ciencias Exactas y Naturales, Departamento de Química Orgánica, Buenos Aires, Argentina. Electronic address:
    Trypanosoma cruzi, the etiologic agent of Chagas disease, is covered by a dense glycocalix mainly composed by glycoproteins called mucins which are also the acceptors of sialic acid in a reaction catalyzed by a trans-sialidase (TcTS). Sialylation of trypomastigote mucins protects the parasite from lysis by the anti α-Galp antibodies from serum. The TcTS is essential for the infection process since T. Read More

    Membrane-enclosed multienzyme (MEME) synthesis of 2,7-anhydro-sialic acid derivatives.
    Carbohydr Res 2017 Nov 19;451:110-117. Epub 2017 Aug 19.
    Quadram Institute Bioscience, The Gut Health and Food Safety Institute Strategic Programme, Norwich Research Park, Norwich NR4 7UA, UK. Electronic address:
    Naturally occurring 2,7-anhydro-alpha-N-acetylneuraminic acid (2,7-anhydro-Neu5Ac) is a transglycosylation product of bacterial intramolecular trans-sialidases (IT-sialidases). A facile one-pot two-enzyme approach has been established for the synthesis of 2,7-anhydro-sialic acid derivatives including those containing different sialic acid forms such as Neu5Ac and N-glycolylneuraminic acid (Neu5Gc). The approach is based on the use of Ruminoccocus gnavus IT-sialidase for the release of 2,7-anhydro-sialic acid from glycoproteins, and the conversion of free sialic acid by a sialic acid aldolase. Read More

    Genetic and structural elucidation of capsular polysaccharides from Streptococcus pneumoniae serotype 23A and 23B, and comparison to serotype 23F.
    Carbohydr Res 2017 Oct 18;450:19-29. Epub 2017 Aug 18.
    LimmaTech Biologics AG, Grabenstrasse 3, Schlieren, Switzerland.
    Streptococcus pneumoniae is a globally important encapsulated human pathogen with approximately 100 different serotypes recognized. Serogroup 23 consists of serotype 23F, present in licensed vaccines, and emerging serotypes 23A and 23B. Here, we report the previously unknown structures of the pneumococcal capsular polysaccharides serotype 23A and 23B determined using genetic analysis, NMR spectroscopy, composition and linkage analysis and Smith degradation (of polysaccharide 23A). Read More

    Chemical synthesis of guanosine diphosphate mannuronic acid (GDP-ManA) and its C-4-O-methyl and C-4-deoxy congeners.
    Carbohydr Res 2017 Oct 11;450:12-18. Epub 2017 Aug 11.
    Bio-organic Synthesis Group, Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands. Electronic address:
    Described is the first synthesis of guanosine diphosphate mannuronic acid (GDP-ManA), the sugar donor used by algae and bacteria for the production of alginate, an anionic polysaccharide composed of β-d-mannuronic acid (ManA) and α-l-guluronic acid (GulA). Understanding the biosynthesis of these polyanionic polysaccharides on the molecular level, opens up avenues to use and modulate the biosynthesis machinery for biotechnological and therapeutic applications. The synthesis reported here delivers multi-milligram amounts of the GDP-ManA donor that can be used to study the polymerase (Alg8 in Pseudomonas aeruginosa) that generates the poly-ManA chain. Read More

    A carbon tetrachloride-free synthesis of N-phenyltrifluoroacetimidoyl chloride.
    Carbohydr Res 2017 Oct 10;450:10-11. Epub 2017 Aug 10.
    School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Victoria, 3010, Australia. Electronic address:
    N-Phenyltrifluoroacetimidoyl chloride (PTFAI-Cl) is a reagent widely used for the preparation of glycosyl N-phenyltrifluoroacetimidates. However, the most commonly applied method requires carbon tetrachloride, a hepatotoxic reagent that has been phased out under the Montreal Protocol. We report a new synthesis of N-phenyltrifluoroacetimidoyl chloride (PTFAI-Cl) using dichlorotriphenylphosphane and triethylamine. Read More

    One-pot synthesis of oxazolidine-2-thione and thiozolidine-2-thione from sugar azido-alcohols.
    Carbohydr Res 2017 Oct 4;450:1-9. Epub 2017 Aug 4.
    Department of Chemistry, Indian Institute of Technology (IIT), Banaras Hindu University, Varanasi 221005, India. Electronic address:
    A controlled and facile synthesis of various glycosyl 1,3-oxazolidine-2-thiones and 1,3- thiozolidine-2-thiones has been accomplished from corresponding sugar azido alcohols utilizing Staudinger reaction (PPh3 and CS2) via isothiocynate route. A series of reactions were performed to investigate the effects of CS2 and PPh3 on the selectivity of product formed. The excessive addition of CS2 with PPh3(1. Read More

    Erylosides F8, V1-V3, and W-W2 - New triterpene oligoglycosides from the Carribean sponge Erylus goffrilleri.
    Carbohydr Res 2017 Sep 4;449:153-159. Epub 2017 Aug 4.
    G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far East Division of the Russian Academy of Science, 690022, Vladivostok, Russia.
    Seven new triterpene glycosides, erylosides F8 (1), V1 (2), V2 (3), V3 (4), W (5), W1 (6) and W2 (7), were isolated from a Carribean sponge Erylus goffrilleri collected from the Carribean Sea near the Arrecife-Seco reef (Cuba). Structures of the glycosides were determined using (1)H and (13)C NMR spectroscopy, including 2D NMR procedures ((1)H-(1)H COSY, (1)H-(13)С HMBC, (1)H-(13)С HSQC and NOESY) and HR ESI mass spectrometry. Erylosides 1 and 4 have 14-carboxy-24,25-dimethyllanost-8(9)-en-3β,25-diol as aglycone whereas glycosides 2, 3, 5, 6 and 7 are 14-carboxy-24-acetoxy-24-methyllanost-8(9)-en-3β-ol glycoconjugates. Read More

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