Convergent synthesis of a galactofuranosylated mannan, the repeating unit of Trichophyton mentagrophytes IFO 5466 and Trichophyton rubrum IFO 5467
作者:Zuchao Ma、Jianjun Zhang、Fanzuo Kong
DOI:10.1016/j.tetasy.2004.03.041
日期:2004.5
An undecasaccharide repeating unit of the polysaccharide of Trichophyton mentagrophytes IFO 5466 and Trichophyton rubrum IFO 5467, alpha-D-Manp-(1 --> 2)-alpha-D-Manp-(1 --> 6)-[beta-D-Galf-(1 --> 3)]-alpha-D-Manp-(1 --> 2)-[beta-D-Galf-(1 --> 3)]-alpha-D-Manp(1 --> 2)-alpha-D-Manp-(1 --> 2)-alpha-D-Manp-(1 --> 6)-alpha-D-Manp-(1 --> 2)-[beta-D-Galf-(1 --> 3)]-Manp was synthesized as its allyl glycoside by coupling of a octasaccharide trichloroacetimidate donor 19 with a trisaccharide acceptor 28. The donor 19 and 28 were obtained with allyl 3-O-acetyl-2-O-betizoyl-alpha-D-mannopyranoside 2, allyl 3-O-acetyl-4,6-di-O-benzoyl-alpha-D-mannopyranoside 9, allyl 3,4,6-tri-O-benzoyl-alpha-D-mannopyranosyl-(1 --> 2)-3,4,6-tri-O-belizoyl-alpha-D-mannopyranoside 13, 6-O-acetyl-2,3,4-tri-O-benzoyl-alpha-D-mannopyranosyl trichloroacetimidate 26 and 2,3,5,6-tetra-O-benzoyl-beta-D-galactofuraliosyl trichloroacetimidate 16 as the key synthons by appropriate combination through simple transformation. (C) 2004 Elsevier Ltd. All rights reserved.