Galactose 3,4,6-tri-O-methyl

Numerous workers have confirmed the above formula for raffinose. Methylation analysis by Haworth and his associates gave 2,3,4,6-tetra-O-methyl-D-galactose, 2,3,4-tri-O-methyl-D-glucose, and 1,3,4,6-tetra-O-methyl-D-f ructose.18i 19... 

Tri-O-methyl-D-glucose 3.4.6- Tri-O-methyl-D-glucose 3.5.6- Tri-O-methyl-D-galactose 2.3.5- Tri-O-methyl-D-galactose 2,3,4-Tri-O-methyl-D-mannose 3.4.6- Tri-O-methyl-D-mannose. 2... 

Total ion chromatogram penta-O-methyl-mono-O-acetylmyoinositol derived from mono-linked myoinositol, 2,3,4,6-tetra-0-methyl-l,5-di-0-acetylgalactitol derived from a terminal galactose, 2,3,6-tri-O-methyl-l, 4,5-tri-O-acetylglucitol derived from a 4-linked glu-citol, and 3,6-di-O-methyl-l, 4,5-tri-0-acetyl-2-acetamido-2-N-methylglucitol from a 4-linked S-acetylglucosamine. 

Tri-O-methyl-D-galactose-(6 —> 1) 2,3,4-tri-O-methyl-D-glucosiduronic acid Acacia pycnantha gum B 0 70c... 

In agreement with the earlier findings,126 approximately equimolecular proportions of 2,3,4,6-tetra-, 2,3,4-tri-, and 2,4-di-O-methyl-D-galacto-pyranose were isolated as the main products of hydrolysis of methylated e-galactan, but, in addition, small proportions of 2,3,4-tri-O-methyl-L-arabinose, 2,5-di-O-methyl-L-arabinose, and 2,4,6-tri- and 2-mono-0-methyl-D-galactose were found. Evidence in favor of partial structure XLI for the galactan framework was obtained by application to the polysac-... 

Mild, acid hydrolysis of European-larch arabinogalactan results in the formation of 3-0-/3-L-arabinopyranosyl-L-arabinose (XXXIX). 26 Although this disaccharide has been isolated as an acid-reversion product from L-arab-inose,131 it is accompanied under these conditions by two other arabinose-containing disaccharides, neither of which was detected in the larch polysaccharide hydrolyzate. Since hydrolysis of methylated -galactan gave approximately equimolar proportions of 2,3,4-tri-O-methyl-L-arabinose and 2,5-di-O-methyl-n-arabinose, traces of 2,3,5-tri-O-methyl-L-arabinose, and no mono-O-methyl-L-arabinose, it is clear that the L-arabinose units must arise from an arabinogalactan rather than from an arabinan, and that the majority of these must be present in 3-0-/3-L-arabinopyranosyl-L-arabino-furanose side-chains (XLV) linked, in some way as yet unknown, to the framework of D-galactose units (XLI). 

All values in mole per cent. Small amount. Large amount. 2,3,4.6-T etra-0-meth l-D- -galactose + 2,3,5-tri-O-methyl-i arabinose. ... 

An L-arabino-D-galactan, in 2% yield, has been isolated from the fruits of Dillenia indica. From the results of partial acid hydrolysis and methylation analyses, when 2,6-di-O-methyl-D-galactose, 2,3,6-tri-O-methyl-D-galactose, 2,3,4,6-tetra-(9-methyl-D-galactose, and 2,3,5-tri-O-methyl-L-arabinose residues in the molar ratio 7 3 1 8 were identified, it was concluded that the polysaccharide was a (1- 4)-j3-D-galactan that contained L-arabinofuranose residues linked at 0-3 of some of the D-galactose residues in the main chain. 

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