Selective fragmentation of methylated tobacco extracellular arabinoglucuronomannan by cleavage of β-d-glucopyranosiduronic acid units

✍ Scribed by Gerald O. Aspinall; Lev Khondo; Velupillai Puvanesarajah

• Book ID: 102990089
• Publisher: Elsevier Science
• Year: 1989
• Tongue: English
• Weight: 559 KB
• Volume: 188
• Category: Article
• ISSN: 0008-6215
• DOI: 10.1016/0008-6215(89)84064-9

✦ Synopsis

Permethylated extracellular arabinoglucuronomannan from suspensioncultured tobacco cells has been subjected to the following sequence of reactions: (i) saponification, (ii) decarboxylation-acetoxylation with lead tetraacetate, and (iii) reductive cleavage of the derived 5acetoxypentopyranosidic linkages with sodium borohydride to give a series of 4-O-a-D-mannopyranosyl-D-xylitol derivatives with and without L-arabinofuranosyl side-chain substituents. The oligosaccharidealditols have been separated, and characterized on the basis of n.m.r.-and massspectral data and of compositional analysis of (trideuteriomethyl)ated derivatives. The results provided evidence for alternating sequences of 4-linked p-D-glucosyluranic acid and 2-linked a-o-mannosyl residues in the main chain, with LU-Larabinofuranosyl groups attached to O-3 of some of the former, and P-L-arabinofuranosyl groups attached to O-3 of some of the latter residues.