Disaccharides methylation

We briefly present here a conformational analysis of the disaccharide, methyl (4-0-P-D-xylopyranosyl-p-D-xylopyranoside)... 

In order to investigate in more detail the combining site on the P-methyl glycoside of the gal-oc-(l - 4)-gal disaccharide ( methyl urobioside ) recognised by the p-fim-... 

C-bis-galactose C-sucrose C-sucrose octa-Ac-(1-4)-C-disaccharides Methyl C-cellobioside Methyl C-maltosIde (1-6)-C-disaccharides Methyl C-gentloblosIde... 

Titanium-based catalysts, would seem particularly attractive candidates, but the pore size of e.g. TS-1, is much too small to admit even a monosaccharide. Recently a number of synthetic approaches towards mesoporous titanium containing catalysts of the MCM-41 type have appeared in the literature . In the present paper we will deseribe the use of Ti-MCM-41 materials in the oxidation of the model mono- and disaccharides methyl a-D-glucopyranoside, sucrose and a,a-trehalose, and we will discuss the effect of the zeolite synthesis on the effectiveness in these reactions. Several preparative approaches of Ti-MCM-41 have been compared in the oxidation of these model carbohydrates. 

The disaccharide methyl 2-0-(a-L-fucopyranosyl)-P-D-galactopyranoside. The 16-membered macrolide antibiotic chalcomycin, which contains chalcose (16) and mycinose (17) as monosaccharide subunits and the macrocyclic lactone... 

In the area of galactose disaccharides, methyl 2,, 6-trl- -benzoyl B-D-galactopyranoside and the corresponding glycosyl acetate have been made for use in the synthesis of (1 - 3)-B-D-galactose linked oligosaccharides, and the dimeric compound (29), from which a trimer can be synthesized, has been reported. ... 

Monosaccharides, disaccharides, methyl sugars, glycosides, cyclitols, sugar alcohols Chromatographic paper (Whatman 3) 0.2 mol r Sodium tetraborate, pH 10.0 0.05 mol r sodium tetraborate, pH 9.5 500 V, 1300-1400V Aniline-hydrogen phthalate... 

Trehalose is a nonreducing disaccharide that is hydrolyzed by aqueous acid to yield 2 equivalents of D-glucose. Methylation followed by hydrolysis yields 2 equivalents of 2,3,4,6-tetra-O-methylglucose. How many structures are possible for trehalose ... 

If the 3- and 4-hydroxyl groups constitute the Shallenberger AH,B unit, it is possible that a disaccharide (such as a,a-trehalose) and methyl a-D-glucopyranoside may possess the same molar sweetness. By a ranking procedure, and using trained panelists in a Paired Comparison Test, it was, indeed, found that isomolar solutions of these two sugars are equi-... 

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