Linear Pentasaccharides

1 Linear Pentasaccharides. - Several glucopentaoses have been reported. The a-l,2-linked compound which is a pentamer fragment of polysaccharide II of Mycobacterium tuberculosis, has been synthesized, and the p-l,3-Iinked isomer has been obtained by acetolysis, followed by hydrolysis, of curdlan and converted to the dodecyl glycoside which was then partially sulfated to give a product showing some anti-HIV activity.Chemo-enzymic methods have been used in 

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Scheme 16 One-pot preparation of a linear pentasaccharides using three leaving groups...

Linear Pentasaccharides.— The following pentamers with reducing D-glucose groups have been made by chemical methods a-D-Ga pNAc-(1 3)-P-D-Ga pNAc-(l- 3)-a-D-Gal/ ... 

The capsular polysaccharide of Diplococcus pneumoniae has been shown to possess a linear pentasaccharide repeating unit containing residues of d-glucopyranosyluronic acid, o-galactofuranose, and L-rhamnopyranose (1 2 2). ° The presence of 2,3-linked D-galactofuranosyl residues in the polysaccharide of Klebsiella K41 has been confirmed by the characterization of 5,6-di-O-methyl-D-galactofuranose as a product in the methylation of the polysaccharide, and of the presence of L-arabinose in the Smith degradation... 

Linear Pentasaccharides.-The effect of different bulky substituents at C-6 of the nonreducing terminal unit of a glycoside of maltopentaoside on the rates of hydrolysis ty human salivary and pancreatic a-amylases has been studied. Several methyl ethers of the pentasaccharide unit of heparin responsible for antithrombin binding have been reported. ... 

Linear Pentasaccharides.—Syntheses of the following have been reported O-a-D-NeupAc-(2- 3)-0-p-D-Ga p-(l- 3)-0-p-D-Ga pNAc-(l- 4)-0-(3-D-Ga p-(l- 4)-0-(3-D-Glfirst synthesis of gong/ib-ganglioside GMlb)the isomer having 2-acetamido-... 

Another type of polylactosamine branching was reported by Anne Leppanen et al. [42]. In their experiments, the doubly labeled linear pentasaccharide GlcNAc(pl-3)[ H]Gal(pi-4)GlcNAc(pi-3)[ C]Gal(pi-4)GlcNAc was converted... 

Preparation of linear oligomer, followed by macrocyclization was demonstrated in the case of cyclic pentaose. A cyclomaltopentaose synthesis was achieved by Nakagawa and coworkers through preparation of a linear pentasaccharide 10 (Fig. 7). The linear pentasaccharide was obtained by first utilizing judiciously equipped maltose derivative I (Fig. 8) as an acceptor in a glycosylation with a suitably protected... 

Jain, R. K. Matta, K. L., Chemical synthesis of a hexasaccharide comprising the Lewis(x) determinant linked beta-(l->6) to a linear trimannosyl core and the precursor pentasaccharide lacking fucose. Carbohydr. Res. 1996,282, 101-111. 

The structures of the classical A and M antigens of Brucella were recently shown to be hompolymers of 4,6-dideoxy-4-formamido-a-D-mannopyranose [102, 103]. The A antigen was an a-l,2-linked polymer, while the M antigen was also linear but was composed of a pentasaccharide repeating unit of four a-1,2- and one a-l,3-linked residues. 

Compound 65 is a linear, reducing pentasaccharide containing four Man residues that has been isolated from the urine of a patient suffering from mannosidosis.52-61 The 500-MHz, H-n.m.r. spectrum of 65 is depicted in Fig. 48, and its relevant, n.m.r.-spectral parameters are listed in Table XXV. 

Love, K R, Andrade, R B, Seeberger, P H, Linear synthesis of a protected H-type II pentasaccharide using glycosyl phosphate building blocks, J. Org. Chem., 66, 8165-8176, 2001. 

In another synthesis of the rat brain Thy-1 GPI anchor, Schmidt and coworkers [88] have adopted the linear strategy to construct the pentasaccharide building block. As shown in O Scheme 11, after all monosaccharide units were obtained, they were assembled sequentially by the trichloroimidate glycosylation method to form pentasaccharide 130. It was manipulated... 

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