Monoacylation of 2- O-α- d-glucopyranosyl- l-ascorbic acid by protease in N, N-dimethylformamide with low water content

Abstract

2- O-α- d-Glucopyranosyl- l-ascorbic acid (AA-2G) laurate was synthesized from AA-2G and vinyl laurate with a protease from Bacillus subtilis in N, N-dimethylformamide (DMF) with low water content. Addition of water to DMF dramatically enhanced monoacyl AA-2G synthesis. Maximum synthetic activity was observed when 3% (v/v) water was added to the reaction medium. Under the optimal reaction conditions, 5- O-dodecanoyl-2- O-α- d-glucopyranosyl- l-ascorbic acid, 2- O-(6′- O-dodecanoyl-α- d-glucopyranosyl)- l-ascorbic acid, and 6- O-dodecanoyl-2- O-α- d-glucopyranosyl- l-ascorbic acid were synthesized in yields of 5.5%, 3.2%, and 20.4%, respectively.