Showing papers on "Glycal published in 1989"
TL;DR: Synthese d'oligosaccharides a partir de tri-O-benzyl-3,4,6 glucal, de di-Obenzoyl- 3,4 glucal et d'hexofuranoses ou dhexopyranoses proteges as mentioned in this paper.
Abstract: Synthese d'oligosaccharides a partir de tri-O-benzyl-3,4,6 glucal, de di-O-benzoyl-3,4 glucal et d'hexofuranoses ou d'hexopyranoses proteges
152 citations
TL;DR: In this article, a pyranoid glycal derivatives with acid-labile protecting groups (acetal, ether, ester) were obtained in excellent yields, and a β-linked 2′-deoxydisaccharide glycal derivative was also prepared from the corresponding disaccharides phenyl thioglycoside.
79 citations
TL;DR: La synthese du squelette pyranno [2,3b] pyranne de la brevetoxine B est effectuee; le compose obtenu comporte un phosphonium quaternaire as discussed by the authors.
Abstract: La synthese du squelette pyranno [2,3-b] pyranne de la brevetoxine B est effectuee; le compose obtenu comporte un phosphonium quaternaire
77 citations
TL;DR: In this paper, the synthesis of the bicyclic acetals 8 from the glycal 1 using a radical cyclization reaction was described, and the synthesis process was described in detail.
44 citations
TL;DR: Bis (trichloroethyl) azodicarboxylate is an efficient diene in the [4+2] cycloaddition reaction with glycals and offers several advantages over the previously described dibenzyl azodicarate (DBAD) which was used to prepare 2-amino glycosides.
39 citations
TL;DR: In this paper, an effective and convenient one-pot procedure, simply involving treatment with boron trifluoride/3-chloroperbenzoic acid (MCPBA), is detailed for the high-yield acquisition of enantiomerically pure dihydropyran-2-ones from mono-and disaccharide-derived glycal and hydroxyglycal esters.
33 citations
TL;DR: Synthese du compose du titre a partir de galactal via des intermediaires O-cholestanyl ou O-methyl or O-cresyl-heptopyranosidulose-2onates de methyle qui sont ensuite decarboxyles par le chlorure d'oxathiazolo-1,4,2 [2.3]-pyridinium.
31 citations
TL;DR: In this article, the naphthylsulphenate ester of 2-hydroxytetralone was used to produce 2-deoxy-β-glycosides as models for the aureolic acid antibiotics.
Abstract: Glucals have been reacted with the naphthylsulphenate ester of 2-hydroxytetralone to afford 2-thio-β-glycosides, which are treated with Raney Ni to produce 2-deoxy-β-glycosides as models for the aureolic acid antibiotics.
27 citations
TL;DR: Trans-addition of iodoazide to the double bond of 3,4,6-tri-O -acetyl-1,5-anhydro-d - arabino -hex-1-enitol yielded 2-deoxy-2-iodoglycosyl azides, which are precursors of 1,2- trans -2-amino-2deoxyglycopyranosides when treated by an alcohol in the presence of triphenylphosphine as mentioned in this paper.
22 citations
TL;DR: In this article, the electroreduction of tetra-O-acetyl-α-D-glucopyranosyl bromide has been studied in dipolar aprotic solvents at mercury electrodes.
21 citations
TL;DR: Les diholosides sont prepared a partir d'aminoglycosides proteges et de didesoxy-2,3 octeno-2 pyranosulose-2 onate de methyle as mentioned in this paper.
TL;DR: In this article, the stereospecific synthesis of a bicyclic precursor for thromboxane B 2, using palladium mediated transformations of tri-O-acetyl-D-glucal, is described.
Abstract: The stereospecific synthesis of a bicyclic precursor for thromboxane B 2 , using palladium mediated transformations of tri-O-acetyl-D-glucal, is described
TL;DR: Synthese d'anhydro-1,5 desoxy-2 di-O-acetyl-3,4 O-tosyl-6 (ou Sacetyl -6) hexene-1 itol (ou thio-6 hexene 1 itol) a partir de D-glucose and de chlorure d'acide p-toluenesulfonique (ou de thioacetate de potassium) as discussed by the authors.
TL;DR: Synthese des composes du titre a partir de cyanure de bromo-1 tetra-O-acetyl-2,3,4,6 galactopyranosyle (ou de son analogue D-arabino) traite avec de la poudre de zinc dans l'acide acetique (ou avec du cyanure of mercure dans le nitromethane)
TL;DR: In this article, a 1,4-addition of hydrazoic acid to a corresponding hex-2-enopyranose was used to synthesize a 4-O(2,6-dideoxy)-α-L-arabinopyranosyl analogue.
Abstract: The methyl 4-O-(2,6-dideoxy-2-iodo-α-L-mannopyranosyl)-α-L-acosaminide (11) and the methyl 4-O-(2,6-dideoxy-α-L-arabinopyranosyl)-α-L-acosaminide analogue (12) have been stereoselectively synthesized in seven and eight steps, respectively, from di-O-acetyl-L-rhamnal (4) and methyl 2,3,6-trideoxy-α-L-erythro-hex-2-enopyranoside (5); the key step involved a 1,4-addition of hydrazoic acid to a corresponding hex-2-enopyranose.
TL;DR: In this paper, a one-pot procedure for the preparation of chiral building blocks, by treatment of O-benzyl glycals 10, 11, 12 and cyclic enol-ethers 1, 3 and 7 with the system Tl(NO3)3 and NaBH4 is described.
Patent•
05 May 1989
TL;DR: In this article, a single-pot single step procedure for the azidochlorination or diazidization of glycals, including glycal elements of carbohydrates, is described.
Abstract: The invention describes a one-pot single step procedure for the azidochlorination or diazidization of glycals, including glycal elements of carbohydrates. Compounds such as 3,4,6-tri-O-benzyl-2-azido-2-deoxy-alpha-D-galactopyranosyl chloride, and 3,4,6-tri-O-benzyl-2-azido-2-deoxy-alpha-,beta-D-galactopyranose are prepared from tri-O-benzyl galactal as well as 3,4,6-tri-O-acetyl-2-azido-2-deoxy-D-alpha-galactopyranosyl chloride and 3,6,-di-O-acetyl-4-O-[2,3,4,6-tetra-O-acetyl-beta-D-galactopyranosyl]-2-azido-2-deoxy-alpha-D-glycopyranosyl chloride from their respective O-acetylated glycal derivatives by the addition of azido chloride which is chemically generated in situ. A method using 3,4,6-tri-O-acetyl-2-azido-2-deoxy-alpha-D-galacto-pyranosyl chloride for the synthesis of antigenic determinants such as the terminal asialo GM₁(beta-D-Gal (1->3)-beta-D-GalNAc-OR) has been demonstrated. The conversion of the subject synthon into 3,4,6-tri-O-acetyl-2-azido-2-deoxy-alpha-D-galactopyranosyl bromide and 1,3,4,6-tetra-O-acetyl-2-azido-2-deoxy-alpha-D-galactopyranose is also described. A further method for the synthetic generation of the Tn antigen (alpha-D-GalNAc-O-L-serine) is also described.
Journal Article•
TL;DR: Les α-L-acosaminide de methyle et de benzyle and le glycal de la Lacosamine (amino-3 tridesoxy-2,3,6-Larabinohexose) ont ete prepares de facon stereoselective par addition-1,4 de l'acide azothydrique sur le L-erythro-hex-2 enopyranose comme etape cle..
Abstract: Les α-L-acosaminide de methyle et de benzyle et le glycal de la L-acosamine (amino-3 tridesoxy-2,3,6-L-arabino-hexose) ont ete prepares de facon stereoselective par addition-1,4 de l'acide azothydrique sur le L-erythro-hex-2 enopyranose comme etape cle. L'inversion de configuration du C-4 de l'azido-3 tridesoxy-2,3,6 L-arabinohexopyranoside de methyle par action du propionate de cesium conduit au derive N-trifluoroacetyle de l'α-L-daunosaminide de methyle ou trifluoroacetamido-3 tridesoxy-2,3,6 α-L-lyxo-hexose
Journal Article•
TL;DR: In this article, an effective and convenient one-pot procedure, simply involving treatment with boron trifluoride/3-chloroperbenzoic acid (MCPBA), is detailed for the high-yield acquisition of enantiomerically pure dihydropyran-2-ones from mono-and disaccharide-derived glycal and hydroxyglycal esters.