19165-11-8Relevant academic research and scientific papers
One-Pot Relay Glycosylation
Cai, Lei,Fang, Jing,Li, Ting,Song, Zejin,Sun, Jiuchang,Wan, Qian,Xiao, Xiong,Zeng, Jing
supporting information, p. 5498 - 5503 (2020/04/09)
A novel one-pot relay glycosylation has been established. The protocol is characterized by the construction of two glycosidic bonds with only one equivalent of triflic anhydride. This method capitalizes on the in situ generated cyclic-thiosulfonium ion as the relay activator, which directly activates the newly formed thioglycoside in one pot. A wide range of substrates are well-accommodated to furnish both linear and branched oligosaccharides. The synthetic utility and advantage of this method have been demonstrated by rapid access to naturally occurring phenylethanoid glycoside kankanoside F and resin glycoside merremoside D.
A practical synthesis of α-D-Manp-(1→3)-α-D-Manp- (1→2)-[α-D-Glcp-(1→3)]-α-D-Manp-(1→2) -α-D-Manp-(1→2)-α-D-Manp, an O-specific heterohexasaccharide fragment of Citrobacter braakii O7a, 3b, 1c
Chen, Langqiu,Kong, Fanzuo
, p. 2169 - 2175 (2007/10/03)
An O-specific heterohexasaccharide fragment of Citrobacter braakii O7a, 3b, 1c, α-D-Manp-(1→3)-α-D-Manp-(1→2)-[α-D-Glcp- (1→3)]-α-D-Manp-(1→2)-α-D-Manp-(1→2)-α-D-Manp was synthesized as its methyl glycoside. Acetylation of allyl 4,6-O-benzylidene-α-D-mannopyranoside, followed by debenzylidenization and benzoylation gave allyl 2,3-di-O-acetyl-4,6-di-O-benzoyl-α-D- mannopyranoside (3), and subsequent deacetylation of 3 with CH 3COCl-MeOH gave the monosaccharide acceptor 4. Condensation of isopropyl 2,3,4,6-tetra-O-benzyl-1-thio-β-D-glucopyranoside (6) with 4 selectively afforded the α-(1→3)-linked disaccharide 7. Condensation of 7 with the (1→3)-linked disaccharide donor 9, followed by deallylation and trichloroacetimidation, afforded the tetrasaccharide donor 12. Coupling of 12 with disaccharide acceptor 13, followed by debenzylation and deacylation, furnished the target heterohexasaccharide 16.
Glycosylimidates, 8. - Synthesis of 1-Thioglycosides
Schmidt, Richard R.,Stumpp, Michael
, p. 1249 - 1256 (2007/10/02)
As expected, the reactive acetyl-protected O-(α-D-glucopyranosyl) trichloroacetimidate 3 reacts with S-nucleophiles and trifluoroborane-ether as catalyst to yield exclusively 1-thio-β-D-glucopyranosides with inversion of the configuration.The corresponding benzyl-protected α-trichloroacetimidate 4 affords with retention of the configuration alkyl 1-thio-α-D-glucopyranosides.The importance of alkyl 1-thio-β-D-galactopyranosides in enzyme induction was reason to apply this convenient and efficient glycosyl-transfer reaction to the synthesis of isopropyl 1-thio-β-D-galactopyranoside (12a) and the sodium salt of 1-thio-β-D-galactopyranose (12b), respectively.
