Synthesis of 4-(3-azidopropoxy)phenyl glycoside of tetraarabinofuranoside related to the terminal fragment of arabinogalactan and lipoarabinomannan of mycobacteria

A convergent synthesis of tetraarabinofuranoside β-d-Araf-(1→2)-α-d-Araf-(1→3)-α-d-Araf-(1→5)-α-d-Araf-1↑OR (R is 4-(3-azidopropoxy)phenyl) related to the terminal fragment of lipoarabinomannan (LAM) and arabinogalactan of mycobacteria was developed. The synthesized tetraarabinofuranoside represents a linear motif of a branched hexaarabinofuranoside, which is the main LAM epitope. 4-(3-Azidopropoxy)phenyl aglycone belongs to the class of Janus aglycones, which can serve as both a temporary protective group for the anomeric position of carbohydrate and a (pre)spacer for the synthesis of neoglycoconjugates useful for the development of new tuberculosis diagnostic assays. The key step of the synthesis is the formation of 1,2-cis-glycosidic bond.