Synthesis of oligosaccharide fragments of the glycosylinositolphospholipid of Trypanosoma cruzi: a new selenoglycoside glycosyl donor for the preparation of 4-thiogalactofuranosyl analogues
作者:Karla D Randell、Blair D Johnston、Ernest E Lee、B.Mario Pinto
DOI:10.1016/s0957-4166(99)00498-x
日期:2000.1
A new selenoglycoside, phenyl 2,3,5,6-tetra-O-acetyl-4-thio-1-selenogalactofuranose, has been synthesized. This 4-thiogalactofuranosyl donor was used in the syntheses of heteroatom analogues of the di-, tri-, and tetrasaccharides corresponding to the oligosaccharide beta-D-Galf-(1-->3)-alpha-D-Manp-(1-->2)-(beta-D-Galf-(1-->3))-alpha-D-Manp. These compounds represent fragments of the terminal end of the glycosylinositolphospholipid oligosaccharide found in the protozoan Trypanosoma cruzi, the causative agent of Chagas disease, and are intended for use as inhibitors of the enzymes that construct the native oligosaccharides. The syntheses employed the selective activation of a phenyl 4-thio-1-selenogalactofuranoside glycosyl donor over ethyl 1-thioglycoside glycosyl accepters with NIS/TfOH. (C) 2000 Elsevier Science Ltd. All rights reserved.