Synthesis of Oligosaccharide Mimetics with Glycoaminoxy Acids

From readily available di‐O‐isopropylidene‐D‐glucose, a D‐ribofuranoid glycoaminoxy acid and its tBu ester have been efficiently prepared as a new family of sugar building blocks by introducing the phthalimido aminoxy group by a Mitsunobu reaction. We found that the tBu ester can be selectively deprotected with 13.7 % TFA in CH₂Cl₂ at 0 °C in the presence of the 1,2‐O‐isopropylidene acetal. This selective deprotection has made possible the synthesis of homo‐oligomers of glycoaminoxy acids (up to six sugar units) as a novel type of oligosaccharide mimetics. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)