Functional group tolerance in organocatalytic regioselective acylation of carbohydrates
Yoshihiro Ueda1, Wataru Muramatsu, Kenji Mishiro
1Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
Abstract:
Organocatalytic regioselective acylation of mono- and disaccaharides with various functionalized acid anhydrides has been developed. Acylation of octyl beta-D-glucopyranoside with acid anhydrides derived from alpha-amino acids, cinnamic acid, and gallic acid took place at C(4)-OH with 67-94% regioselectivity in the presence of catalyst 1. Regioselective acylation of disaccharides with functionalized acid anhydrides was also achieved with 78-94% selectivity. Especially, a disaccharide with seven free hydroxy groups (X = OH, R' = H) underwent acylation at C(4)-OH with 78% regioselectivity in the presence of 1. Thus, functional group tolerance in the regioselective acylation catalyzed by 1 was found to be high.
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