Journal ArticleDOI
C(1 -> 4)-linked disaccharides through carbonylative Stille cross-coupling
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TLDR
A tinglucal tributyl and triflate derived from isolevoglucosenone (1R,4R,5R)-4-benzyloxy-6,8-dioxabicyclo[3.2.1] undergo the carbonylative Stille condensation under special conditions requiring AsPh3, LiCl, and powdered charcoal as co-catalysts to give a cross-conjugated dienone 6 in which the bicyclic alkene moiety is more reactive than the glucal alkAbstract:
A tinglucal tributyl[4,6-O-bis(t-butyl)silylidene-3-O-tris(isopropyl)silyl]tin 7 and a triflate derived from isolevoglucosenone (1R,4R,5R)-4-benzyloxy-6,8-dioxabicyclo[3.2.1]oct-2-en-2-yl trifluoromethanesulfonate 10 undergo the carbonylative Stille condensation under special conditions requiring AsPh3, LiCl, and powdered charcoal as co-catalysts to give a cross-conjugated dienone 6 in which the bicyclic alkene moiety is more reactive than the glucal alkene moiety. This allows the regio- and stereoselective hydrogenation of the bicyclic alkene moiety giving an enone 21 that can be reduced stereoselectively to an allylic alcohol 22. Hydroboration of the glucal and bicyclic acetal opening generates a C(1-->4) linked disaccharide 25 in which a protected form of beta-D-glucopyranose is attached at position C(4) of a alpha-D-3-deoxy-ribo-hexopyranoside derivative via a (S)-hydroxymethano linker. (C) 2004 Elsevier Ltd. All rights reserved.read more
Citations
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Palladium-catalyzed carbonylation reactions of aryl halides and related compounds.
TL;DR: The recent academic developments in palladium-catalyzed carbonylation reactions of aromatic halides in the presence of various nucleophiles are summarized and the first industrial processes are summarized.
Journal ArticleDOI
Palladium-catalyzed carbonylative coupling reactions between Ar–X and carbon nucleophiles
TL;DR: A critical review of the development of palladium-catalyzed carbonylative coupling reactions of aromatic halides and related compounds with carbon nucleophiles with palladium catalysts concludes that these reactions are important intermediates in the manufacture of dyes, pharmaceuticals, agrochemicals, and other industrial products.
Interactions and the initiation of the inflammatory response
TL;DR: This review focuses on the various biochemical aspects of the interactions between the selectins and their cognate carbohydrate ligands, with an emphasis on the importance of these adhesive events to the inflammatory response.
Journal ArticleDOI
Palladiumkatalysierte Carbonylierungen von Arylhalogeniden und ähnlichen Substraten
TL;DR: In this article, eine CO-Gruppe reicher: (Hetero-)Arene sind aus der industriellen Herstellung von Agrochemikalien, Farbstoffen, Pharmaka etc. nicht wegzudenken.
Journal ArticleDOI
Recent Advances in the Chemical Synthesis of C-Glycosides
TL;DR: Mechanistically, C-glycosylation reactions can involve glycosyl electrophilic/cationic species, anionic species, radical species, or transition-metal complexes, which are discussed as subcategories under each type of sugar precursor.
References
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Journal ArticleDOI
The Palladium‐Catalyzed Cross‐Coupling Reactions of Organotin Reagents with Organic Electrophiles [New Synthetic Methods (58)]
TL;DR: The cross-coupling of organotin reagents with a variety of organic electrophiles, catalyzed by palladium, provides a novel method for generating a carbon-carbon bond.
Journal ArticleDOI
Glycosylation and the immune system
TL;DR: Almost all of the key molecules involved in the innate and adaptive immune response are glycoproteins, and specific glycoforms are involved in recognition events.
Journal Article
Chemical glycobiology : Carbohydrates and glycobiology
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Journal ArticleDOI
Selectin ligands
TL;DR: This review analyzes the matter and suggests the hypothesis that at least some of the specificity of the selectins may involve recognition of "clustered saccharide patches."
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