作者:Paul B. van Seeventer、Johannis P. Kamerling、Johannes F.G. Vliegenthart
DOI:10.1016/s0008-6215(97)00013-x
日期:1997.4
To contribute to the possibility of studying in greater detail the biological significance of Sd(a)-containing glycans as occur in Tamm-Horsfall glycoprotein, the following three spacer-linked tetrasaccharides have been synthesized: the Sd(a) determinant alpha-Neup5Ac-(2 --> 3)-[beta D-GalpNAc-(1 --> 4)]-beta-D-Galp-(1 --> 4)-beta-D-GlcpNAc-(1 --> 0)(CH2)(5)NH2 (1), the Gal-analogue alpha-Neup5Ac-(2 --> 3)-[beta-D-Galp-(1 --> 4)]-beta-D-Galp-(1 --> 4)-beta-D-GlcpNAc-(1 --> 0)(CH2)(5)NH2 (2), and the GlcNAc-analogue alpha-Neup5Ac-(2 --> 3)-[beta-D-GlcpNAc-(1 --> 4)]-beta-D-Galp-(1 --> 4)-beta-D-GlcpNAc-(1 --> 0)(CH2)(5)NH2 (3). The general trisaccharide acceptor 5-azidopentyl (methyl 5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-D-glycero-alpha-D-galacto-non-2-ulopyranosylonate)-(2 --> 3)-(2,6-di-O-benzyl-beta-D-galactopyranosyl)-(1 --> 4)-3,6-di-O-benzyl-2-deoxy-2-phthalimido-beta-D-glucopyranoside was prepared, using methyl (phenyl 5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-2-thio-D-glycero-D-galacto-non-2-ulopyranosid)-onate as the sialyl donor. For the syntheses of 1, 2, and 3 the glycosyl donors 3,4,6-tri-O-acetyl-2-deoxy-2-phthalimido-alpha-D-galactopyranosyl bromide, 2,3,4,6-tetra-O-acetyl-alpha-D-galactopyranosyl bromide, and 3,4,6-tri-O-acetyl-2-deoxy-2-phthalimido-beta-D-glucopyranosyl trichloroacetimidate, respectively, proved to be the most suitable. (C) 1997 Elsevier Science Ltd.