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Abramov AA, Zinin AI, Kolotyrkina NG, Kononov LO, Shatskiy A, Kärkäs MD, Stepanova EV. Mild and General Protocol for Selective Deacetylation of Acetyl/Benzoyl-Protected Carbohydrates. J Org Chem 2024; 89:10021-10026. [PMID: 38955329 DOI: 10.1021/acs.joc.4c00900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/04/2024]
Abstract
Herein, we report a mild and general protocol for chemoselective deacetylation of mixed acetyl- and benzoyl-protected carbohydrates under mild acidic conditions. The protocol allows quick access to partially protected carbohydrates, which serve as versatile synthetic intermediates during the total synthesis of various mono- and oligosaccharide targets. The applicability of the developed protocol was successfully demonstrated on a range of carbohydrate substrates of various configurations and substitution patterns featuring functionalized aliphatic and aromatic aglycones. The protocol has shown excellent compatibility with the widely used O-anomeric protecting groups, prespacer aglycones, and thioglycoside glycosyl donors.
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Affiliation(s)
| | - Alexander I Zinin
- Laboratory of Glycochemistry, N. D. Zelinsky Institute of Organic Chemistry of the Russian Academy of Sciences, Leninsky prosp. 47, 119991 Moscow, Russia
| | - Natalya G Kolotyrkina
- Laboratory of Glycochemistry, N. D. Zelinsky Institute of Organic Chemistry of the Russian Academy of Sciences, Leninsky prosp. 47, 119991 Moscow, Russia
| | - Leonid O Kononov
- Laboratory of Glycochemistry, N. D. Zelinsky Institute of Organic Chemistry of the Russian Academy of Sciences, Leninsky prosp. 47, 119991 Moscow, Russia
| | - Andrey Shatskiy
- Department of Chemistry, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
| | - Markus D Kärkäs
- Department of Chemistry, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
| | - Elena V Stepanova
- Tomsk Polytechnic University, Lenin Avenue 30, 634050 Tomsk, Russia
- Department of Chemistry, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
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2
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Gurawa A, Kumar M, Kashyap S. Me 3SI-promoted chemoselective deacetylation: a general and mild protocol. RSC Adv 2021; 11:19310-19315. [PMID: 35478635 PMCID: PMC9033574 DOI: 10.1039/d1ra03209g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Accepted: 05/16/2021] [Indexed: 11/21/2022] Open
Abstract
A catalytic and practical approach for the selective removal of acetyl groups using various substrates bearing orthogonal moieties has been demonstrated under ambient conditions.
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Affiliation(s)
- Aakanksha Gurawa
- Carbohydrate Chemistry Research Laboratory (CCRL)
- Department of Chemistry
- Malaviya National Institute of Technology Jaipur, (MNIT)
- Jaipur-302017
- India
| | - Manoj Kumar
- Carbohydrate Chemistry Research Laboratory (CCRL)
- Department of Chemistry
- Malaviya National Institute of Technology Jaipur, (MNIT)
- Jaipur-302017
- India
| | - Sudhir Kashyap
- Carbohydrate Chemistry Research Laboratory (CCRL)
- Department of Chemistry
- Malaviya National Institute of Technology Jaipur, (MNIT)
- Jaipur-302017
- India
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3
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Gurawa A, Kumar M, Rao DS, Kashyap S. KMnO 4-catalyzed chemoselective deprotection of acetate and controllable deacetylation–oxidation in one pot. NEW J CHEM 2020. [DOI: 10.1039/d0nj04321d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
A highly chemoselective and facile protocol for deacetylation of a diverse range of substrates tolerating several sensitive functionalities was accomplished under environmentally friendly conditions.
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Affiliation(s)
- Aakanksha Gurawa
- Carbohydrate Chemistry Research Laboratory (CCRL)
- Department of Chemistry
- Malaviya National Institute of Technology
- Jaipur-302017
- India
| | - Manoj Kumar
- Carbohydrate Chemistry Research Laboratory (CCRL)
- Department of Chemistry
- Malaviya National Institute of Technology
- Jaipur-302017
- India
| | - Dodla S. Rao
- Carbohydrate Chemistry Research Laboratory (CCRL)
- Department of Chemistry
- Malaviya National Institute of Technology
- Jaipur-302017
- India
| | - Sudhir Kashyap
- Carbohydrate Chemistry Research Laboratory (CCRL)
- Department of Chemistry
- Malaviya National Institute of Technology
- Jaipur-302017
- India
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4
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Zhang X, Dickinson DM, Lin L, Suflita M, Baytas S, Linhardt RJ. Chemoenzymatic synthesis of heparan sulfate tetrasaccharide from a N-acetyl-α-d-glucosamine-O-methylglycoside acceptor. Tetrahedron Lett 2019. [DOI: 10.1016/j.tetlet.2019.02.036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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5
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Møller BL, Olsen CE, Motawia MS. General and Stereocontrolled Approach to the Chemical Synthesis of Naturally Occurring Cyanogenic Glucosides. JOURNAL OF NATURAL PRODUCTS 2016; 79:1198-202. [PMID: 26959700 DOI: 10.1021/acs.jnatprod.5b01121] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
An effective method for the chemical synthesis of cyanogenic glucosides has been developed as demonstrated by the synthesis of dhurrin, taxiphyllin, prunasin, sambunigrin, heterodendrin, and epiheterodendrin. O-Trimethylsilylated cyanohydrins were prepared and subjected directly to glucosylation using a fully acetylated glucopyranosyl fluoride donor with boron trifluoride-diethyl etherate as promoter to afford a chromatographically separable epimeric mixture of the corresponding acetylated cyanogenic glucosides. The isolated epimers were deprotected using a triflic acid/MeOH/ion-exchange resin system without any epimerization of the cyanohydrin function. The method is stereocontrolled and provides an efficient approach to chemical synthesis of other naturally occurring cyanogenic glucosides including those with a more complex aglycone structure.
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Affiliation(s)
- Birger L Møller
- Carlsberg Laboratory , 10 Gamle Carlsberg Vej, 1799 Copenhagen V, Denmark
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6
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Gauthier C, Chassagne P, Theillet FX, Guerreiro C, Thouron F, Nato F, Delepierre M, Sansonetti PJ, Phalipon A, Mulard LA. Non-stoichiometric O-acetylation of Shigella flexneri 2a O-specific polysaccharide: synthesis and antigenicity. Org Biomol Chem 2016; 12:4218-32. [PMID: 24836582 DOI: 10.1039/c3ob42586j] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Synthetic functional mimics of the O-antigen from Shigella flexneri 2a are seen as promising vaccine components against endemic shigellosis. Herein, the influence of the polysaccharide non-stoichiometric di-O-acetylation on antigenicity is addressed for the first time. Three decasaccharides, representing relevant internal mono- and di-O-acetylation profiles of the O-antigen, were synthesized from a pivotal protected decasaccharide designed to tailor late stage site-selective O-acetylation. The latter was obtained via a convergent route involving the imidate glycosylation chemistry. Binding studies to five protective mIgGs showed that none of the acetates adds significantly to broad antibody recognition. Yet, one of the five antibodies had a unique pattern of binding. With IC50 in the micromolar to submicromolar range mIgG F22-4 exemplifies a remarkable tight binding antibody against diversely O-acetylated and non-O-acetylated fragments of a neutral polysaccharide of medical importance.
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Affiliation(s)
- Charles Gauthier
- Institut Pasteur, Chimie des Biomolécules, Dépt de Biologie Structurale et Chimie, 28 rue du Dr Roux, 75724 Paris Cedex 15, France.
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7
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Dai X, Liu W, Zhou Q, Cheng C, Yang C, Wang S, Zhang M, Tang P, Song H, Zhang D, Qin Y. Formal Synthesis of Anticoagulant Drug Fondaparinux Sodium. J Org Chem 2015; 81:162-84. [PMID: 26650028 DOI: 10.1021/acs.joc.5b02468] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The practical formal synthesis of the anticoagulant drug fondaparinux sodium 1 was accomplished using an optimized modular synthetic strategy. The important pentasaccharide 2, a precursor for the synthesis of fondaparinux sodium, was synthesized on a 10 g scale in 14 collective steps with 3.5% overall yield from well-functionalized monosaccharide building blocks. The strategy involved a convergent [3 + 2] coupling approach, with excellent stereoselectivity in every step of glycosylation from the monosaccharide building blocks. Efficient routes to the syntheses of these fully functionalized building blocks were developed, minimizing oligosaccharide stage functional-group modifications. The syntheses of all building blocks avoided rigorous reaction conditions and the use of expensive reagents. In addition, common intermediates and a series of one-pot reactions were employed to enhance synthetic efficiency, improving the yield considerably. In the monosaccharide-to-oligosaccharide assembly reactions, cheaper activators (e.g., NIS/TfOH, TESOTf, and TfOH) were used to facilitate highly efficient glycosylations. Furthermore, crystallization of several monosaccharide and oligosaccharide intermediates significantly simplified purification procedures, which would be greatly beneficial to the scalable synthesis of fondaparinux sodium.
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Affiliation(s)
- Xiang Dai
- Innovative Drug Research Centre, Chongqing University , Chongqing, 401331, China
| | - Wentao Liu
- Innovative Drug Research Centre, Chongqing University , Chongqing, 401331, China
| | - Qilong Zhou
- Innovative Drug Research Centre, Chongqing University , Chongqing, 401331, China
| | - Chunwei Cheng
- Key Laboratory of Drug Targeting and Drug Delivery Systems of the Ministry of Education, West China School of Pharmacy, Sichuan University , Chengdu, 610041, China
| | - Chao Yang
- Innovative Drug Research Centre, Chongqing University , Chongqing, 401331, China
| | - Shuqing Wang
- Innovative Drug Research Centre, Chongqing University , Chongqing, 401331, China
| | - Min Zhang
- Innovative Drug Research Centre, Chongqing University , Chongqing, 401331, China
| | - Pei Tang
- Innovative Drug Research Centre, Chongqing University , Chongqing, 401331, China
| | - Hao Song
- Key Laboratory of Drug Targeting and Drug Delivery Systems of the Ministry of Education, West China School of Pharmacy, Sichuan University , Chengdu, 610041, China
| | - Dan Zhang
- Key Laboratory of Drug Targeting and Drug Delivery Systems of the Ministry of Education, West China School of Pharmacy, Sichuan University , Chengdu, 610041, China
| | - Yong Qin
- Key Laboratory of Drug Targeting and Drug Delivery Systems of the Ministry of Education, West China School of Pharmacy, Sichuan University , Chengdu, 610041, China
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Zhou J, Yang L, Hu W. Stereoselective synthesis of a sulfated tetrasaccharide corresponding to a rare sequence in the galactofucan isolated from Sargassum polycystum. J Org Chem 2014; 79:4718-26. [PMID: 24766314 DOI: 10.1021/jo500503r] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The first chemical synthesis of a highly sulfated tetrasaccharide 1, as the rare sequence in the galactofucan isolated from the brown alga Sargassum polycystum, was achieved in a convergent and stereoselective manner. The key features of the synthetic strategy include construction of multiple contiguous 1,2-cis glycosidic bonds and [2 + 2] assembly based on the rationally developed d-galactose building block 6. The synthesized oligosaccharides were fully characterized using a combination of coupled-HSQC and other 2D NMR techniques.
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Affiliation(s)
- Jun Zhou
- Shanghai Engineering Research Centre of Molecular Therapeutics and New Drug Development, and Department of Chemistry, East China Normal University , Shanghai, 200062, PR China
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9
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Iwata R, Sudo M, Nagafuji K, Wada T. Synthesis of oligodiaminosaccharides having α-glycoside bonds and their interactions with oligonucleotide duplexes. J Org Chem 2011; 76:5895-906. [PMID: 21688799 DOI: 10.1021/jo200951p] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Syntheses of the novel oligodiaminosaccharides, α-(1→4)-linked-2,6-diamino-2,6-dideoxy-D-glucopyranose oligomers, and their interactions with nucleic acid duplexes DNA-DNA, RNA-RNA, and DNA-RNA are described. Monomers to tetramers of oligodiaminoglucose derivatives having α-glycosyl bonds were successfully synthesized using a chain elongation cycle including glycosylation reactions of a 6-phthalimide glycosyl donor. UV melting experiments for a variety of nucleic acid duplexes in the absence and presence of the oligodiaminosaccharides were performed. The synthesized oligodiaminosaccharides exhibited notable thermodynamic stabilization effects on A-type RNA-RNA and DNA-RNA duplexes, whereas B-type DNA-DNA duplexes were not stabilized by the synthesized oligodiaminosaccharides. Among the oligodiaminosaccharides, the tetramer exhibited the highest ability to stabilize A-type duplexes, and the increase in T(m) values induced by the tetramer were higher than those induced by neomycin B and tobramycin, which are known aminoglycosides having ability to bind and stabilize a variety of RNA molecules. CD spectrometry experiments revealed that the oligodiaminosaccharides caused small structural changes in RNA-RNA duplexes, whereas no appreciable changes were observed in the structure of DNA-DNA duplexes. ITC (isothermal titration calorimetry) experiments demonstrated that the amount of heat generated by the interaction between RNA-RNA duplexes and the tetradiaminosaccharides was approximately double that generated by that between DNA-DNA duplexes and the tetradiaminosaccharides. These results strongly suggested the existence of an A-type nucleic acid specific-binding mode of the oligodiaminosaccharides, which bind to these duplexes and cause small structural changes.
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Affiliation(s)
- Rintaro Iwata
- Department of Medical Genome Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Bioscience Building 702, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8562, Japan
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10
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Santra A, Misra AK. Synthesis of tri- and pentasaccharide fragments corresponding to the O-antigen of Shigella boydii type 6. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/j.tetasy.2010.10.032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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11
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Tasca JE, Ponzinibbio A, Diaz G, Bravo RD, Lavat A, González MG. CuFe2O4 Nanoparticles: A Magnetically Recoverable Catalyst for Selective Deacetylation of Carbohydrate Derivatives. Top Catal 2010. [DOI: 10.1007/s11244-010-9538-0] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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12
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Somogyi L, Batta G. Formation and structure elucidation of N-(2,3,4-tri-O-acetyl-β-d-glucopyranosyl)-N′-acetylthiourea. Carbohydr Res 2009; 344:134-5. [DOI: 10.1016/j.carres.2008.08.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2008] [Accepted: 08/11/2008] [Indexed: 10/21/2022]
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13
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Boutet J, Guerreiro C, Mulard LA. Synthesis of branched tri- to pentasaccharides representative of fragments of Shigella flexneri serotypes 3a and/or X O-antigens. Tetrahedron 2008. [DOI: 10.1016/j.tet.2008.08.080] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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14
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15
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Costachel C, Sansonetti PJ, Mulard LA. Linear Synthesis of the Methyl Glycosides of Tetra- and Pentasaccharide Fragments Specific for the Shigella flexneri Serotype 2a O-Antigen. J Carbohydr Chem 2008. [DOI: 10.1080/07328300008544139] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Corina Costachel
- a Unité de Chimie Organique, BGM, and Unité de Pathogénie Microbienne Moléculaire, BGM, Institut Pasteur , 28 rue du Dr. Roux, 75724 Paris, Cedex 15, France
- b Unité de Chimie Organique, BGM, and Unité de Pathogénie Microbienne Moléculaire, BGM, Institut Pasteur , 28 rue du Dr. Roux, 75724 Paris, Cedex 15, France
- c Unité de Chimie Organique, BGM, and Unité de Pathogénie Microbienne Moléculaire, BGM, Institut Pasteur , 28 rue du Dr. Roux, 75724 Paris, Cedex 15, France
| | - Philippe J. Sansonetti
- a Unité de Chimie Organique, BGM, and Unité de Pathogénie Microbienne Moléculaire, BGM, Institut Pasteur , 28 rue du Dr. Roux, 75724 Paris, Cedex 15, France
- b Unité de Chimie Organique, BGM, and Unité de Pathogénie Microbienne Moléculaire, BGM, Institut Pasteur , 28 rue du Dr. Roux, 75724 Paris, Cedex 15, France
- c Unité de Chimie Organique, BGM, and Unité de Pathogénie Microbienne Moléculaire, BGM, Institut Pasteur , 28 rue du Dr. Roux, 75724 Paris, Cedex 15, France
| | - Laurence A. Mulard
- a Unité de Chimie Organique, BGM, and Unité de Pathogénie Microbienne Moléculaire, BGM, Institut Pasteur , 28 rue du Dr. Roux, 75724 Paris, Cedex 15, France
- b Unité de Chimie Organique, BGM, and Unité de Pathogénie Microbienne Moléculaire, BGM, Institut Pasteur , 28 rue du Dr. Roux, 75724 Paris, Cedex 15, France
- c Unité de Chimie Organique, BGM, and Unité de Pathogénie Microbienne Moléculaire, BGM, Institut Pasteur , 28 rue du Dr. Roux, 75724 Paris, Cedex 15, France
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16
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Du Y, Lin J, Linhardt RJ. Regioselective Synthesis of L-Idopyranuronic Acid Derivatives: Intermolecular Aglycon Transfer of Dithioacetal Under Standard Glycosylation Conditions. J Carbohydr Chem 2006. [DOI: 10.1080/07328309708005753] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Yuguo Du
- a Division of Medicinal and Natural Products Chemistry and Department of Chemical and Biochemical Engineering , The University of Iowa , PHAR-S328, Iowa City, IA, 52242, USA
| | - Jihong Lin
- a Division of Medicinal and Natural Products Chemistry and Department of Chemical and Biochemical Engineering , The University of Iowa , PHAR-S328, Iowa City, IA, 52242, USA
| | - Robert J. Linhardt
- a Division of Medicinal and Natural Products Chemistry and Department of Chemical and Biochemical Engineering , The University of Iowa , PHAR-S328, Iowa City, IA, 52242, USA
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17
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Coxon B, Sari N, Mulard LA, Kovac P, Pozsgay V, Glaudemans CPJ. Investigation by NMR Spectroscopy and Molecular Modeling of the Conformations of Some Modified Disaccharide Antigens forShigella DysenteriaeType 1. J Carbohydr Chem 2006. [DOI: 10.1080/07328309708006549] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Bruce Coxon
- a Biotechnology Division, National Institute of Standards and Technology , Gaithersburg, Maryland, 20899, USA
| | - Nese Sari
- a Biotechnology Division, National Institute of Standards and Technology , Gaithersburg, Maryland, 20899, USA
| | - Laurence A. Mulard
- b Laboratory of Medicinal Chemistry, National Institute of Diabetes, and Digestive and Kidney Diseases, National Institutes of Health , Bethesda, Maryland, 20892, USA
| | - Pavol Kovac
- b Laboratory of Medicinal Chemistry, National Institute of Diabetes, and Digestive and Kidney Diseases, National Institutes of Health , Bethesda, Maryland, 20892, USA
| | - Vince Pozsgay
- b Laboratory of Medicinal Chemistry, National Institute of Diabetes, and Digestive and Kidney Diseases, National Institutes of Health , Bethesda, Maryland, 20892, USA
- c Laboratory of Developmental and Molecular Immunity, National Institute of Child Health and Human Development, National Institutes of Health , Bethesda, Maryland, 20892, USA
| | - C. P. J. Glaudemans
- b Laboratory of Medicinal Chemistry, National Institute of Diabetes, and Digestive and Kidney Diseases, National Institutes of Health , Bethesda, Maryland, 20892, USA
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Zhou Y, Lin F, Chen J, Yu B. Toward synthesis of the regular sequence of heparin: synthesis of two tetrasaccharide precursors. Carbohydr Res 2006; 341:1619-29. [PMID: 16529732 DOI: 10.1016/j.carres.2006.02.020] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2006] [Revised: 02/15/2006] [Accepted: 02/21/2006] [Indexed: 11/24/2022]
Abstract
Two fully protected tetrasaccharides, which represent precursors for the synthesis of the regular sequence of heparin, were synthesized via coupling of a pair of disaccharide trichloroacetimidates with a thioglycoside and a glucosamine derivative, respectively, in a sequential manner.
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Affiliation(s)
- Ying Zhou
- State Key Laboratory of Bio-organic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China
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19
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Bélot F, Wright K, Costachel C, Phalipon A, Mulard LA. Blockwise Approach to Fragments of the O-Specific Polysaccharide of Shigella flexneri Serotype 2a: Convergent Synthesis of a Decasaccharide Representative of a Dimer of the Branched Repeating Unit1. J Org Chem 2004; 69:1060-74. [PMID: 14961653 DOI: 10.1021/jo035125b] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The D'A'B'(E')C'DAB(E)C decasaccharide representative of a dimer of a frame-shifted pentasaccharide repeating unit of the O-specific polysaccharide of Shigella flexneri 2a was synthesized as its methyl glycoside by condensing a pentasaccharide donor (D'A'B'(E')C') and a pentasaccharide acceptor (DAB(E)C-OMe). Several convergent routes to these two building blocks, involving either the AB linkage or the BC linkage as the disconnection site, were evaluated in comparison to the linear strategy. The latter was preferred. It is based on the use of the trichloroacetimidate chemistry. The target branched oligosaccharide was designed to probe the recognition at the molecular level of the natural polysaccharide by protective monoclonal antibodies.
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Affiliation(s)
- Frédéric Bélot
- Unité de Chimie Organique, URA CNRS 2128, INSERM 389, Institut Pasteur, Paris, France
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Mukhopadhyay B, Roy N. Synthesis of the pentasaccharide related to the repeating unit of the antigen from Shigella dysenteriae type 4 in the form of its methyl ester 2-(trimethylsilyl)ethyl glycoside. Carbohydr Res 2003; 338:589-96. [PMID: 12644371 DOI: 10.1016/s0008-6215(02)00499-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Starting from D-mannose, D-glucose and L-fucose, the pentasaccharide derivative methyl 2,3,4-tri-O-benzyl-alpha-L-fucopyranosyl-(1-->3)-2-O-acetyl-4,6-O-benzylidene-alpha-D-mannopyranosyl-(1-->3)-2-O-acetyl-6-O-benzyl-4-O-(2,3,4-tri-O-benzyl-alpha-L-fucopyranosyl)-alpha-D-mannopyranosyl-(1-->4)-[2-(trimethylsilyl)ethyl 2,3-di-O-benzyl-beta-D-glucopyranosid]uronate was synthesized. This compound with two alpha-mannopyranosyl units was transformed, via Walden inversion and subsequent deprotection, into the alpha-D-glucosamine-type target compound, namely methyl alpha-L-fucopyranosyl-(1-->3)-2-acetamido-2-deoxy-alpha-D-glucopyranosyl-(1-->3)-2-acetamido-2-deoxy-4-O-(alpha-L-fucopyranosyl)-alpha-D-glucopyranosyl-(1-->4)-[2-(trimethylsilyl)ethyl beta-D-glucopyranosid]uronate which is related to the repeating unit of the O-antigen from Shigella dysenteriae type 4.
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Affiliation(s)
- Balaram Mukhopadhyay
- Department of Biological Chemistry, Indian Association for the Cultivation of Science, Jadavpur, 700 032, Calcutta, India
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21
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Mulard LA, Clément MJ, Segat-Dioury F, Delepierre M. Synthesis and NMR study of a linear pentasaccharide fragment of the Shigella flexneri 5a O-specific polysaccharide. Tetrahedron 2002. [DOI: 10.1016/s0040-4020(02)00148-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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22
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Nyholm PG, Mulard LA, Miller CE, Lew T, Olin R, Glaudemans CP. Conformation of the O-specific polysaccharide of Shigella dysenteriae type 1: molecular modeling shows a helical structure with efficient exposure of the antigenic determinant alpha-L-Rhap-(1-->2)-alpha-D-Galp. Glycobiology 2001; 11:945-55. [PMID: 11744629 DOI: 10.1093/glycob/11.11.945] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The O-specific polysaccharide of Shigella dysenteriae type 1, which has the repeating tetrasaccharide unit -->3)-alpha-L-Rhap-(1-->3)-alpha-L-Rhap-(1-->2)-alpha-D-Galp-(1-->3)-alpha-D-GlcNAcp-(1--> (A-B-C-D), is a major virulence factor, and it is believed that antibodies against this polysaccharide confer protection to the host. The conformational properties of fragments of this O-antigen were explored using systematic search with a modified HSEA method (GLYCAN) and with molecular mechanics MM3(96). The results show that the alpha-D-Gal-(1-->3)-alpha-D-GlcNAc linkage adopts two favored conformations, phi/psi approximately equal to -40 degrees /-30 degrees (I) and approximately 15 degrees /30 degrees (II), whereas the other glycosidic linkages only have a single favored phi/psi conformational range. MM3 indicates that the trisaccharide B-C-D and tetrasaccharides containing the B-C-D moiety exist as two different conformers, distinguished by the conformations I and II of the C-D linkage. For the pentasaccharide A-B-C-D-A' and longer fragments, the calculations show preference for the C-D conformation II. These results can explain previously reported nuclear magnetic resonance data. The pentasaccharide in its favored conformation II is sharply bent, with the galactose residue exposed at the vertex. This hairpin conformation of the pentasaccharide was successfully docked with the binding site of a monoclonal IgM antibody (E3707 E9) that had been homology modeled from known crystal structures. For fragments made of repetitive tetrasaccharide units, the hairpin conformation leads to a left-handed helical structure with the galactose residues protruding radially at the helix surface. This arrangement results in a pronounced exposure of the galactose and also the adjacent rhamnose in each repeating unit, which is consistent with the known role of the as alpha-L-Rhap-(1-->2)-alpha-D-Galp moiety as a major antigenic epitope of this O-specific polysaccharide.
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Affiliation(s)
- P G Nyholm
- Department of Medical Biochemistry and Centre for Structural Biology, University of Göteborg, Medicinaregatan 7, 405 30 Göteborg, Sweden
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González AG, Brouard I, León F, Padrón JI, Bermejo J. A facile chemoselective deacetylation in the presence of benzoyl and p-bromobenzoyl groups using p-toluenesulfonic acid. Tetrahedron Lett 2001. [DOI: 10.1016/s0040-4039(01)00406-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Pozsgay V. Oligosaccharide-protein conjugates as vaccine candidates against bacteria. Adv Carbohydr Chem Biochem 2001; 56:153-99. [PMID: 11039111 DOI: 10.1016/s0065-2318(01)56004-7] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- V Pozsgay
- National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892-2720, USA
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Mukherjee I, Das SK, Mukherjee A, Roy N. Synthesis of the tetrasaccharide related to the repeating unit of the antigen from Shigella dysenteriae type 5. Carbohydr Res 2000; 325:245-52. [PMID: 10839118 DOI: 10.1016/s0008-6215(00)00011-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Starting from L-rhamnose, D-mannose and 2-amino-2-deoxy-D-glucose hydrochloride, two disaccharide blocks, namely, ethyl 2,4-di-O-benzyl-3-O-[(R)-1-(methoxycarbonyl)ethyl]-alpha-L-rhamnopyranos yl-(1-->3)-2-O-acetyl-4,6-di-O-benzyl-1-thio-alpha-D-mannopyranoside and 2-(trimethylsilyl)ethyl 2-O-acetyl-3,6-di-O-benzyl-alpha-D-mannopyranosyl-(1-->3)-4,6-di-O-benzy l-2-deoxy-2-phthalimido-beta-D-glucopyranoside, were synthesised and then allowed to react in the presence of N-iodosuccinimide and trifluoromethane sulfonic acid to give a tetrasaccharide derivative. This compound was converted into 2-(trimethylsilyl)ethyl 2,4-di-O-benzyl-3-O-[(R)-1-(methoxycarbonyl)ethyl]-alpha-L-rhamno- pyranosyl-(1-->3)-2-O-acetyl-4,6-di-O-benzyl-alpha-D-mannopyranosyl-(1-- >4)-2-O-acetyl-3,6-di-O-benzyl-alpha-D-mannopyranosyl-(1-->3)-2-acetamid o-4,6-di-O-benzyl-2-deoxy-beta-D-glucopyranoside, which on hydrogenolysis, afforded the methyl ester 2-(trimethylsilyl)ethyl glycoside of the tetrasaccharide related to the repeating unit of the O-antigen from Shigella dysenteriae type 5.
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Affiliation(s)
- I Mukherjee
- Department of Biological Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Calcutta
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26
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Abstract
[formula: see text] The synthesis of two hyaluronan trisaccharides, methyl O-(beta-D-glucopyranosyluronic acid)-(1,3)-O-(2-acetamido-2-deoxy-beta-D-glucopyranosyl)-(1,4)-O-beta-D- glucopyranosiduronic acid and methyl O-(2-acetamido-2-deoxy-beta-D-glucopyranosyl)-(1,4)-O-beta- D-glycopyranosyluronic acid)-(1,3)-O-(2-acetamido-2-deoxy-beta-D-glucopyranoside, are described. Construction of the target molecules was achieved though a combination of the phenyl sulfoxide and trichloroacetimidate glycosylation methodologies. This is the first report on the synthesis of the beta-methyl derivatives, which represent the smallest fragments that incorporate all the structural features of polymeric hyaluronan.
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Coxon B, Sari N, Batta G, Pozsgay V. NMR spectroscopy, molecular dynamics, and conformation of a synthetic octasaccharide fragment of the O-specific polysaccharide of Shigella dysenteriae type 1. Carbohydr Res 2000; 324:53-65. [PMID: 10723612 DOI: 10.1016/s0008-6215(99)00278-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
A synthetic octasaccharide fragment (2) of the O-specific polysaccharide (1) of Shigella dysenteriae type 1 has been studied as its methyl glycoside by one- and two-dimensional homo- and heteronuclear NMR spectroscopy. Complete 1H and 13C NMR assignments have been generated, and the 13C spin-lattice relaxation times have been measured for the octasaccharide 2. A congener (6) of this octasaccharide containing one D-galactose residue with a specific 13C label at C-1 has been synthesized and used to measure interglycosidic 13C-1H coupling by the 2D J-resolved 1H NMR method. From the NMR data, three types of conformational restraints were developed: (a) 29 inter-residue, distance restraints; (b) 48 intra-residue, ring atom dihedral angle restraints, and (c) one heteronuclear, inter-residue dihedral angle restraint. The use of these restraints in a restrained molecular dynamics computation with simulated annealing yielded a conformation resembling a short, irregular spiral, with methyl substituents on the exterior.
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Affiliation(s)
- B Coxon
- Biotechnology Division, National Institute of Standards and Technology, Gaithersburg, MD 20899-8311, USA.
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Mulard LA, Ughetto-Monfrin J. Linear Synthesis of The Methyl Glycosides of Tri-, Tetra-, and Pentasaccharide Fragments of TheShigella FlexneriSerotype 5AO-Antigen. J Carbohydr Chem 2000. [DOI: 10.1080/07328300008544096] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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29
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Westfall DA, Flores RR, Negrete GR, Martinez AO, Haro LS. High-resolution polyacrylamide gel electrophoresis of carbohydrates derivatized with a visible dye. Anal Biochem 1998; 265:232-7. [PMID: 9882397 DOI: 10.1006/abio.1998.2928] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A technique for carbohydrate analysis that is both inexpensive and easily performed is currently unavailable. In this communication we address the problem and have outlined a method for labeling saccharides with a visible dye, 4-amino-1,1'-azobenzene-3, 4'-disulfonic acid, which has an absorption maximum of 489 nm and an extinction coefficient of 37,615, to facilitate visible detection at low levels. The visible dye was coupled by a reductive amination to different sugars. The sugar-dye adducts were then separated by electrophoresis on alkaline polyacrylamide gels. The gels were scanned with a densitometer, and visible sugar-dye adducts were qualitatively analyzed by identifying them according to their mobilities. The sugar-dye adducts were quantified by determining their densitometric volume. The kinetics of the reductive amination reactions, performed at 37 degrees C, were different for each of three saccharides tested. The rate constants for glucose and fucose were 1.31 times greater and 1.8 times greater, respectively, than that of maltotriose. The reductive amination reactions were essentially complete after approximately 16 h under the given experimental conditions. A linear dose-response relationship was observed between the amount of sugar (monosaccharide, trisaccharide, or heptasaccharide) in the reductive amination reaction. The quantity of saccharide-dye adduct that could be visually detected for glucose, maltotriose, and maltoheptaose, was 25, 25, and 50 nmol, respectively. Sugar-dye adducts were separated from one another by varying the acrylamide concentration in the polyacrylamide gels. Sugar-dye adducts of monosaccharides, disaccharides, trisaccharides, and heptasaccharides were separated on alkaline 30% polyacrylamide gels with mobilities of 0.778, 0.667, 0.639, and 0.375. Adducts of glucose, fucose, galactose, and mannose were separated with mobilities of 0.844, 0.833, 0.820, and 0.810, respectively, on a 30 to 40% gradient polyacrylamide gel. Adducts of glucose and glucose derivatives were separated on a 35% polyacrylamide gel. This technique provides an inexpensive and easily performed method of carbohydrate analysis to laboratories that do not have the highly trained personnel nor the expensive equipment needed for other methods of carbohydrate analysis. The method is most applicable to research problems where sensitivity (20 pmol) is not a problem. The simplicity of the method also makes it easily incorporated into teaching laboratories.
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Affiliation(s)
- D A Westfall
- Division of Life Sciences, The University of Texas at San Antonio, 6900 North Loop 1604 West, San Antonio, Texas, 78249-0662, USA
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Pozsgay V. Synthesis of Glycoconjugate Vaccines against Shigella dysenteriae Type 1. J Org Chem 1998; 63:5983-5999. [PMID: 11672203 DOI: 10.1021/jo980660a] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Syntheses of a hexadecasaccharide and smaller fragments corresponding to one-four repeating units of the O-specific polysaccharide of Shigella dysenteriae type 1 are reported in a reactive aglycon-linked from. Two tetrasaccharide donor/acceptor repeating units were assembled from monosaccharide precursors in a stepwise fashion and used in a linear, iterative manner to construct the higher-membered saccharides using Schmidt's glycosylation technique that proved superior to others tested. Single-point attachment of the saccharides to human serum albumin, using a secondary heterobifunctional spacer, afforded a range of glycoconjugates for a detailed evaluation of their immunological characteristics.
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Affiliation(s)
- Vince Pozsgay
- Laboratory of Developmental and Molecular Immunity, National Institute of Child Health and Human Development, National Institutes of Health, 6 Center Dr. MSC 2720, Bethesda, Maryland 20892-2720
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Pozsgay V, Sari N, Coxon B. Measurement of interglycosidic 3JCH coupling constants of selectively 13C labeled oligosaccharides by 2D J-resolved 1H NMR spectroscopy. Carbohydr Res 1998; 308:229-38. [PMID: 9675362 DOI: 10.1016/s0008-6215(98)00047-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Tri-, tetra-, and penta-saccharide fragments of the O-specific polysaccharide of Shigella dysenteriae type 1 have been prepared in which a D-galactose residue of each oligosaccharide methyl glycoside derivative contains a 13C label at C-1. The interglycosidic coupling constants (3JCH) of these 13C nuclei with the H-3 nuclei of the adjacent 2-acetamido-2-deoxy-D-glucose residues have been measured by two-dimensional, J-resolved 1H NMR spectroscopy. The magnitudes of these coupling constants indicate that the trisaccharide is conformationally different to the higher oligosaccharide homologs, in agreement with previous studies of 13C chemical shifts and 1JCH values.
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Affiliation(s)
- V Pozsgay
- Laboratory of Developmental and Molecular Immunity, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-2720, USA
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Pozsgay V. SynthetischeShigella-Impfstoffe: ein Kohlenhydrat-Protein-Konjugat mit vollständig synthetischen Hexadecasaccharid-Haptenen. Angew Chem Int Ed Engl 1998. [DOI: 10.1002/(sici)1521-3757(19980116)110:1/2<145::aid-ange145>3.0.co;2-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Pozsgay V, Dubois EP, Pannell L. Synthesis of Kojidextrins and Their Protein Conjugates. Incidence of Steric Mismatch in Oligosaccharide Synthesis. J Org Chem 1997; 62:2832-2846. [PMID: 11671646 DOI: 10.1021/jo962300y] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Kojidextrins are biologically important oligosaccharides that are involved in many physiological processes including protein glycosylation and bacterial growth. As part of our project to explore the role kojidextrins may play in bacterial pathogenesis, here we report synthetic routes to kojibiose (54), -triose (58), -tetraose (64), and -pentaose (69) equipped with alpha-linked (hydrazinocarbonyl)pentyl aglycon, using linear and convergent strategies. In the search for a rapid convergent strategy for the construction of extended kojidextrins, four kojibiose donors (1-4) were synthesized that contain acyl- and ether-type protecting groups in various ratios. These were tested to probe the influence of diverse protecting group assemblies on their glycosyl donor ability. Attempted condensation of these donors with kojitriose and -tetraose acceptors failed to give the desired products apparently because of steric mismatch between the donor and the acceptor moieties. A one-pot procedure was developed for the covalent attachment of the synthetic saccharides through their hydrazido group to human serum albumin (HSA) using Tietze's squarate method to give neoglycoproteins containing up to 28 saccharide units per HSA.
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Affiliation(s)
- Vince Pozsgay
- Laboratory of Developmental and Molecular Immunity, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892-2720, and Laboratory of Bioorganic Chemistry, National Institute of Diabetes, and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
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Pozsgay V, Robbins JB. Synthesis of a pentasaccharide fragment of Polysaccharide II of Mycobacterium tuberculosis. Carbohydr Res 1995; 277:51-66. [PMID: 8548790 DOI: 10.1016/0008-6215(95)00199-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Stereocontrolled, stepwise synthesis of decyl glycosides of alpha-(1-->2)-linked di- to pentaglucosides (1-5) is described; these constitute fragments of Polysaccharide II of Mycobacterium tuberculosis. Phenyl 3,4,6-tri-O-acetyl-2-O-benzyl-1-thio-alpha-D- glucopyranoside (7) was used as the single key intermediate, obtained from 1,3,4,6-tetra-O-acetyl-2-O-benzyl-beta-D-glucopyranose (6) and PhSSiMe3. Halogenolysis of 7 afforded the isolated beta bromide (10) and beta chloride (13). Solvolysis of 10 with decanol without heavy metal salts gave decyl 3,4,6-tri-O-acetyl-2-O-benzyl-alpha-D-glucopyranoside (14) in a highly stereoselective reaction, in high yield. Subsequent, iterative hydrogenolytic removal of the O-benzyl group and glycosylation with the beta-chloride 13 under catalysis by silver salts afforded the protected di- to penta-saccharide glycosides 16, 19, 21, and 23, which were conventionally deblocked.
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Affiliation(s)
- V Pozsgay
- Laboratory of Developmental and Molecular Immunity, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
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35
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Pozsgay V, Coxon B. Stereoselective preparation of alkyl glycosides of 2-acetamido-2-deoxy-alpha-D-glucopyranose by nonclassical halide-ion catalysis and synthesis and NMR spectroscopy of alpha-D-Gal p-(1-->3)-alpha-D-Glc pNAc-OMe. Carbohydr Res 1995; 277:171-8. [PMID: 8548787 DOI: 10.1016/0008-6215(95)00198-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- V Pozsgay
- Laboratory of Developmental and Molecular Immunity, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
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Barresi F, Hindsgaul O. Chemically Synthesized Oligosaccharides, 1994. A Searchable Table of Glycosidic Linkages. J Carbohydr Chem 1995. [DOI: 10.1080/07328309508005396] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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37
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Mulard LA, Claudemans CP. Synthesis of specifically deoxygenated disaccharide derivatives of the Shigella dysenteriae type 1 O-antigen. Carbohydr Res 1995; 274:209-22. [PMID: 7585707 DOI: 10.1016/0008-6215(95)00122-a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The synthesis of methyl O-alpha-L-rhamnopyranosyl-(1-->2)-alpha-D-galactopyranosides specifically deoxygenated at position 2 (31), or 4 (21) of the rhamnopyranosyl residue was accomplished using methyl 3,4,6-tri-O-benzoyl-alpha-D-galactopyranoside (18) as the glycosyl acceptor. Phenyl thionocarbonate activation of the penta-O-benzoylated disaccharide precursor followed by Barton reduction and Zemplén transesterification gave 31, while 21 was obtained via condensation of the deoxygenated monosaccharide donor with 18, and subsequent debenzoylation of the product.
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Affiliation(s)
- L A Mulard
- NIDDK, National Institutes of Health, Bethesda, Maryland 20892, USA
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Pozsgay V, Pannell L. Convergent synthesis of an octasaccharide fragment of the O-specific polysaccharide of Shigella dysenteriae type 1. Carbohydr Res 1994; 258:105-22. [PMID: 7518739 DOI: 10.1016/0008-6215(94)84079-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
A stereocontrolled, convergent synthesis is described of the linear octasaccharide methyl glycoside alpha-L-Rha p-(1-->2)-alpha-D-Gal p-(1-->3)-alpha-Glc p NAc-(1-->3)-al pha-L-Rha p-(1-->3)-alpha-L-Rha p-(1-->2)-alpha-D-Gal p-(1-->3) -alpha-D-Glc p NAc-(1-->3)-alpha-L-Rha p-OMe (11), which corresponds to two contiguous repeating units of the O-specific polysaccharide of Shigella dysenteriae type 1.
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Affiliation(s)
- V Pozsgay
- Laboratory of Developmental and Molecular Immunity, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892
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