Synthesis of (1-->4)-beta-D-xylo-oligosaccharides of dp 4-10 by a blockwise approach.
Dibutyltin oxide-mediated regioselective chloroacetylation of methyl 1-thio-beta-xylobioside, followed by treatment of the product with 4-methylbenzoyl chloride-pyridine, gave methyl 4-O-chloroacetyl-2,3-di-O-(4-methylbenzoyl)-beta-D-xylopyranosyl-(1-->4) -2.3-di - O-(4-methylbenzoyl)-1-thio-beta-D-xylopyranoside (18) in 70% yield. Coupling of 18 with benzyl alcohol afforded the disaccharide benzyl beta-glycoside, which was O-dechloroacetylated to provide methyl 2,3-di-O-(4-methylbenzoyl)-beta-D-xylopyranosyl-(1-->4)-2,3-di-O-(4- methylbenzoyl)-1-thio-beta-D-xylopyranoside (20). A homologous series of (1-->4)-beta-D-xylo-oligosaccharides from the tetra- to the deca-saccharide have been synthesized in a blockwise manner by using 20 as the glycosyl acceptor, 18, methyl 1-thio-beta-xylobioside pentaacetate, and methyl 1-thio-beta-xylotrioside heptaacetate as the glycosyl donors, and a combination of N-iodosuccinimide-silver triflate as the promoter.
Takeo
K
K
Department of Agricultural Chemistry, Kyoto Prefectural University, Japan.
Ohguchi
Y
Y
Hasegawa
R
R
Kitamura
S
S
D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D006027:Glycosides / Q000138:chemical synthesis* / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000138:chemical synthesis* / Q000737:chemistry; D009947:Organotin Compounds / Q000737:chemistry
D006027:Glycosides; D009844:Oligosaccharides; D009947:Organotin Compounds; C010807:xylosides; C031078:dibutyltin oxide