Synthesis of a tetrasaccharide fragment of mycobacterial arabinogalactan

LUCÍA GANDOLFI-DONADIO; CAROLA GALLO-RODRIGUEZ; ROSA M. DE LEDERKREMER

CARBOHYDRATE RESEARCH

Elsevier

Lugar: Amsterdam; Año: 2008 vol. 343 p. 1870 - 1875

0008-6215

The arabinogalactan of mycobacteria contains both monosaccharides in furanose configuration, absent in mammals. We report here the first synthesis of the tetrasaccharide fragment a-D-Araf-(1-5)-b-D-Galf-(1-5)-b-D-Galf-(1-6)-D-Galf conveniently derivatized for further elongation. The strategy relied on the use of suitably substituted D-galactono-1,4-lactones as precursors for the galactofuranose units. Reduction of the lactone tetrasaccharide 9 with disiamylborane afforded the tetrasaccharide synthon 1. The tetrasaccharide contains the linker unit of the arabinan to the galactan.