Enzymatic Preparation of N-Substituted 4-(O-α-D-Glucopyranosylmoranoline Derivatives

Abstract

A transglycosylation reaction with N-substituted moranolines was carried out with soluble starch as the glucose donor and cyclodextrin glycosyltransferase [EC 2.4.1.19] from Bacillus stearothermophilus, the degree of N-substituted moranolines that were converted to transglycosylation products being within the range of 60-81%. The resultant transglycosylation products were hydrolyzed by glucoamylase [EC 3.2.1.3] from Rhizopm niveus, and the degree of N-substituted moranolines that were converted to N-substituted 4-O-α-D-glucopyranosylmoranolines was within the range of 53-72%.
The inhibitory activities of N-substituted 4-O-α-D-glucopyranosyImoranolines against cyclodextrin glycosyltransferase were greater than those of the corresponding N-substituted moranolines, and N-substituted 4-O-α-D-glucopyranosylmoranolines lost the inhibitory activities against glucoamylase. Among these N-substituted 4-O-α-D-glucopyranosylmoranolines, the N-methyl derivative was a very potent inhibitor.