Synthetic studies on oligosaccharides composed of 5-thioglucopyranose units.
Glycosylation reactions of 5-thioglucopyranosyl trichloroacetimidates bearing ethereal protective groups at the 2-O-position 14-15, and 37 proceed smoothly to give alpha-glycosides stereoselectively by using a catalytic amount of silyl triflate. This methodology allowed us to achieve syntheses of sulfur-substituted isomaltotetraoside 2 and maltotetraoside 3. These studies also revealed that benzoyl-protected 5-thioglucopyranosyl trichloroacetimidate 12 underwent beta-selective glycosylation with C6-OH glucopyranosyl acceptors upon activation by BF3OEt2. This was applied for preparation of sulfur-substituted gentiobiosides 1 and 46.
Morii
Yasuharu
Y
Faculty of Agriculture and Life Science, Hirosaki University, 3 Bunkyo-Cho, Hirosaki, Aomori 036-8561, Japan.
Matsuda
Hiroko
H
Ohara
Keiichiro
K
Hashimoto
Masaru
M
Miyairi
Kazuo
K
Okuno
Toshikatsu
T
D002240:Carbohydrate Sequence; D006031:Glycosylation; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000138:chemical synthesis / Q000737:chemistry*; D016339:Spectrometry, Mass, Fast Atom Bombardment; D013863:Thioglucosides / Q000138:chemical synthesis / Q000737:chemistry*
D009844:Oligosaccharides; D013863:Thioglucosides