369641-41-8Relevant academic research and scientific papers
Highly efficient synthesis of the mannose nonasaccharide of the N-glycan expressed on the HIV glycoprotein gp 120
Zhu,Kong
, p. 1217 - 1220 (2001)
A highly concise and effective synthesis of the mannose nonasaccharide of the glycan expressed on the HIV protein gp 120 was achieved via TMSOTf promoted selective 6-glycosylation of a tetrasaccharide 4,6-diol acceptor with a pentasaccharide donor followed by deprotection. The pentasaccharide was constructed by selective 3,6-diglycosylation of 1,2-O-ethylidene-β-D-mannopyranose with 2-O-acetyl-3,4,6-tri-O-benzoyl-α-D-mannopyranosyl-(1→2)-3,4,6- tri-O-benzoyl-α-D-mannopyranosyl trichloroimidate while the tetrasaccharide was obtained by selective 3-O-glycosylation of allyl 4,6-O-benzilidene-α-D-mannopyranoside with 2,3,4,6-tetra-O-benzoyl-α-D-mannopyranosyl-(1→2)-3,4,6-tri-O- benzoyl-α-D-mannopyranosyl-(1→2)-3,4,6-tri-O-benzoyl-α-D- mannopyranosyl trichloroimidate.
Synthesis of α-Manp-(1→2)-α-Manp-(1→3)-α-Manp-(1→3)-Manp, the tetrasaccharide repeating unit of Escherichia coli O9a, and α-Manp-(1→2)-α-Manp-(1→2)-α-Manp-(1→3)- α-Manp-(1→3)-Manp, the pentasaccharide repeating unit of E. coli O9 and Klebsiella O3
Chen, Langqiu,Zhu, Yuliang,Kong, Fanzuo
, p. 383 - 390 (2007/10/03)
The tetrasaccharide repeating unit of Escherichia coli O9a, α-D-Manp-(1→2)-α-D-Manp-(1→3)-α-D-Manp- (1→3)-D-Manp, and the pentasaccharide repeating unit of E. coli O9 and Klebsiella O3, α-D-Manp-(1→2)-α-D-Manp-(1→2)-α-D-Manp- (1→3)-α-D-Manp-(1→3)-D-Manp, were synthesized as their methyl glycosides. Thus, selective 3-O-allylation of p-methoxyphenyl α-D-mannopyranoside via a dibutyltin intermediate gave p-methoxyphenyl 3-O-allyl-α-D-mannopyranoside (2) in good yield. Benzoylation (→3), then removal of 1-O-methoxyphenyl (→4), and subsequent trichloroacetimidation afforded the 3-O-allyl-2,4,6-tri-O-benzoyl-α-D-mannopyranosyl trichloroacetimidate (5). Condensation of 5 with methyl 4,6-O-benzylidene-α-D-mannopyranoside (6) selectively afforded the (1→3)-linked disaccharide 7. Benzoylation of 7, debenzylidenation, benzoylation, and deallylation gave methyl 2,4,6-tri-O-benzoyl-α-D-mannopyranosyl-(1→3)-2,4,6-tri-O-benzoyl- α-D-mannopyranoside (11) as the disaccharide acceptor. Coupling of 11 with (1→2)-linked mannose disaccharide donor 17 or trisaccharide donor 21, followed by deacylation, furnished the target tetrasaccharide and pentasaccharide, respectively.
