Contents Introduction Conformational Analysis of Monosaccharides

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1 Contents 1 Introduction... 1 Stereochemistry Representation of Monosaccharides... 2 Acyclic Form of Monosaccharides... 2 Cyclic Forms of Monosaccharides... 4 The Nomenclature of Carbohydrates... 9 TrivialNames... 9 StemandSystematicNames... 9 Conventions Choice of Parent Monosaccharides Choice Between Alternative Names for Substituted Derivatives.. 11 Configurational Symbols and Prefixes Ketoses Deoxy-monosaccharides Amino-monosaccharides O-Substitution AcyclicForms Anomers and the Anomeric Configurational Symbols ( α or β ) Glycosides Glycosyl Radicals and Glycosylamines Aldonic Acids UronicAcids AldaricAcids CyclicAcetals Intramolecular Anhydrides References Conformational Analysis of Monosaccharides Conformational Analysis of Acyclic Hydrocarbons Conformational Analysis of Acyclic (Aldehydo) Forms of Monosaccharides xi

2 xii Contents Conformational Analysis of Cyclic (Lactol, Hemiacetal) Forms of Monosaccharides Furanoses Pyranoses Calculation of Conformational Energies of Pyranoses References Anomeric Effect Endo-anomeric Effect The Quantum-Mechanical Explanation Exo-anomeric Effect Generalized Anomeric Effect ReverseAnomericEffect AnomericEffectinSystemsO C N References Isomerization of Sugars Mutarotation Anomerization Lobry de Bruyn Alberda van Ekenstein Transformation References Relative Reactivity of Hydroxyl Groups in Monosaccharides Introduction SelectiveAcylation(Esterification) Selective p-toluenesulfonylation (Tosylation) and Methanesulfonylation (Mesylation) Selective Benzoylation SelectiveAcetylation Other Acylating Reagents AcylMigrations Selective Alkylation and/or Arylation of Glycopyranosides Tritylation of Monosaccharides (Triphenylmethyl Ethers) Selective Benzylation of Monosaccharides Selective Alkylation of Metal Complexes of Monosaccharides References Cyclic Acetals and Ketals Acetalation Benzylidenation Ethylidenation Ketalation Isopropylidenation (Acetonation) Transacetalation and Transketalation TheIsomerizationofCyclicAcetalsandKetals TheMigrationofAcetalorKetalGroup Removal of Acetal and Ketal Groups

3 Contents xiii Benzylidene Group Isopropylidene Group References Nucleophilic Displacement and the Neighboring Group Participation Nucleophilic Displacement Nucleophilic Displacements with Neighboring Group Participation. 179 References Anhydrosugars ,6-Anhydrosugars (Glycosanes) ,4-Anhydrosugars ,2-Anhydrosugars(Brigl sanhydrides) AnhydrosugarsNotInvolvingtheAnomericCarbon Epoxides or Oxiranes Rearrangements of Anhydrosugars Epoxide Migration Other Isomerizations of Epoxides References Amino Sugars Ammonolysis of Oxiranes Nucleophilic Displacement of Sulfonates (or Halides) with Nitrogen Nucleophiles Glycosylamines and N-Glycosides Acid-Catalyzed Hydrolysis of Purine and Pyrimidine Nucleosides References Oxidation of Monosaccharides Selective Oxidations of Monosaccharides CatalyticOxidation BromineOxidation Nonselective Oxidation of Secondary Hydroxyl Groups Ruthenium Tetroxide (RuO 4 )Oxidation DimethylSulfoxideOxidation DMSO DCC Method (Pfitzner Moffatt Oxidation) DMSO AceticAnhydrideMethod DMSO Phosphorus Pentoxide DMSO Sulfurtrioxide Pyridine ( Parikh Doering Oxidation) ChromiumTrioxideOxidation Chromium Trioxide Pyridine Oxidation Chromium Trioxide Acetic Acid Pyridinium Chlorochromate NicotineDichromate PyridiniumDichromate AceticAnhydride

4 xiv Contents Oxidation of Carbohydrates with the Cleavage ofcarbohydratechain Periodate Oxidation Lead Tetraacetate Oxidation Pentavalent Organobismuth Reagents References Addition of Nucleophiles to Glycopyranosiduloses The Addition of a Hydride Ion (Reduction) The Addition of Carbon Nucleophiles: Synthesis of Branched ChainSugars The Addition of Organometals Addition of Diazomethane Synthesis of Branched Chain Sugars with Functionalized Branched Chain Lithio-1,3-Dithiane as the Nucleophile Vinyl Carbanion as the Nucleophile Methoxyvinyl Lithium and 1,1-Dimethoxy-2-Lithio-2-Propene ReformatskyReaction Opening of Oxiranes with Nucleophiles References Chemistry of the Glycosidic Bond Introduction Glycoside Synthesis Fischer Glycosidation Königs Knorr Synthesis Synthesis of Acylated Glycosyl Chlorides and Bromides Glycosyl Fluorides in Glycosylation Synthesis of Glycosyl Fluorides Orthoester Method of Glycosidation Trichloroacetimidate Method of Glycosidation Glycoside Synthesis via Remote Activation n-pentenyl Glycosides as Glycosyl Donors Glycals as Glycosyl Donors Thioglycosides as Glycoside Donors Synthesis of Thioglycosides Glycosyl Sulfoxides as Glycosyl Donors Solid-Phase Synthesis of Oligosaccharides Automated Oligosaccharide Synthesis Cleavage of Glycosidic Bonds Acid-Catalyzed Hydrolysis of Glycosides The Acid-Catalyzed Hydrolysis of Glycopyranosides Acid-Catalyzed Hydrolysis of Glycofuranosides Some Recent Developments Regarding the Mechanism of Glycoside Hydrolysis

5 Contents xv Acetolysis of Glycosides References Synthesis of Polychiral Natural Products from Carbohydrates MacrolideAntibiotics:ErythronolidesAandB Thromboxane B Swainsonine Biotin Pseudomonic Acid C Aplasmomycin References Carbohydrate-Based Antibiotics Aminoglycoside Antibiotics Kanamycin Amikacin Gentamicins Tobramycin(Nebramycin) Neomycin B (Actilin, Enterfram, Framecetin, Soframycin) Paromomycin ButirosinsAandB StreptomycinA Orthosomycins DestomycinA Flambamycin Everninomicin References Higher-Carbon Monosaccharides Introduction Synthesis of Higher-Carbon Sugars Wittig Olefination Aldol Condensation The Butenolide Approach Total Synthesis of Higher-Carbon Monosaccharides References Author Index Subject Index

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