Acarbose is a pseudotetrasaccharide with an unsaturated cyclitol [2,3,4-trihydroxy-5-(hydroxymethyl)-5,6-cyclohexene in a D-gluco-configuration] attached to the nitrogen of 4-amino-4, 6-dideoxy-D-glucopyranose, which is linked α-(1→4) to maltose. Acarbose which has used in the treatment diabetes disease is a strong competitive inhibitor of α-glucosidase and α-amylase. Recently, acarbose glucosides have been synthesized as inhibitors for the enzymes related with diabetes.  

In this study, fructosyl-acarbose was synthesized via the acceptor reaction of a levansucrase, obtained from Leuconostoc mesenteroides, with acarbose and sucrose. The transfered products were purified via P-2 column chromatography and HPLC, and the structures were identified in accordance with the results of ¹H, ¹³C, HSQC, H-H COSY, HMBC analyses. The K_i value of acarbose-F1 (0.16 μM) was a little lower than that of acarbose (0.83 μM) with regard to α-amylase (porcine pancreatic).