3-C-carboxy-5-deoxy-L-xylose

RG-n, Rhamnogalacturonan II Kdo, 3-deoxy-D-manno-octulosonic acid Dha, 3-deoxy-D-/yxo-heptulosaric acid aceric acid, 3-C- carboxy-5-deoxy-L-xylose TMS, per-0-trimethylsilylated methyl glycosides. 

Studies on the complex pectic polysaccharide Rhamnogalacturonan-II have shown the presence of the unusual sugar aceric acid (3-C-carboxy-5-deoxy-L-xylose) (Spellman et al., 1983a). By using mild acid hydrolysis (0.1 M trifluoroacetic acid 40°C for 24 h) two complex heptasaccharides (7 and 8), one of which contains aceric acid, have been obtained from Rhamnogalacturonan-Il (Spellman et al., 1983b McNeil et al., 1984). 

C-Carboxy-5-deoxy-L-xylose (1) has been identified for the first time as a plant cell-wall component the xylo-configuration was confirmed by X-ray crystal analysis on the derived lactone (2), and the L-series assignment by conversion to L-lactic acid. ... 

Fig. 3.21. Structure of rhamnogalacturonan II (RG-II) (Doco and Brillouet, 1993). a-o-GalAp galacturonic acid a-D-Galp galactopyranoside /3-L-Rhap /3-L-rhamnopyranose (rhamnose) a-L-Ara/ a-L-arabinofuranose (arabinose) a-L-Fucp = a-L-fucopyranose (fucose) 2-0-Me-a-D-xylose 2-0-methyl-a-D-xylose /3-D-GlcAp /3-D-glucuropyranosic acid (glucuronic acid) /3-D-Api/ /3-D-apiofuranose (apiose) KDOp 3-dioxy-D-manno-2-octululopyranosic acid /3-D-DHA/ /3-deoxy-D-lyxo-2-heptulafuronosic acid /3-L-AceA/ /3-3-C-carboxy-5-deoxy-L-xylofuranose (aceric acid) Me methyl...

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