An efficient and concise synthesis of a beta-(1-->6)-linked D-galactofuranosyl hexasaccharide.
A beta-(1-->6)-linked D-galactofuranosyl hexasaccharide was synthesized efficiently in a block construction manner by the well-known Schmidt glycosylation method using 6-O-acetyl-2,3,5-tri-O-benzoyl-beta-D-galactofuranosyl trichloroacetimidate (1) and allyl 2,3,5-tri-O-benzoyl-beta-D-galactofuranoside (3) as the key synthons. Coupling of 3 with 1 gave beta-(1-->6)-linked disaccharide 4. Subsequent selective deacetylation of 4 afforded the disaccharide acceptor 5, while deallylation of 4 followed by trichloroacetimidate formation produced the disaccharide donor 6. Condensation of 5 with 6 gave the tetrasaccharide 7, and subsequent deacetylation afforded the tetrasaccharide acceptor 8. Finally, coupling of 8 with 6 followed by deacylation yielded the target beta-(1-->6)-linked galactofuranose hexasaccharide 10. All of the reactions in the synthesis were carried out smoothly and in high yield.
Zhang
Guohua
G
Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, PO Box 2871, Beijing 100085, China.
Fu
Mingkun
M
Ning
Jun
J
D002240:Carbohydrate Sequence; D005685:Galactans / Q000138:chemical synthesis* / Q000737:chemistry; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000138:chemical synthesis* / Q000737:chemistry
D005685:Galactans; D009844:Oligosaccharides; C502290:allyl galactofuranosyl-1-6-galactofuranosyl-1-6-galactofuranosyl-1-6-galactofuranoysl-1-6-galactofuranosyl-1-6-galactofuranoside