Biological Effect of Glycosyl-Oxadiazolinethione and Glycosyl-sulfanyloxadiazole Derivatives through their in vitro Inhibition of Glycosidases from Bacteria and Normal or Diabetic Rats

The inhibition of glycosidases from bacteria and the liver of normal and diabetic rats by 2-(tetra-O-acetyl-β-Dglucopyranosylsulfanyl)- 5-(1-benzyl-1H-indol-2-yl)-1,3,4-oxadiazole BnM-3B; 3-(2,3,4,6-tetra-O-acetyl-β-D-galactopyranosyl)- 5-(1H-indol-2-yl)-1,3,4-oxadiazole- 2(3H)-thione MTB-4A; 3-(2-acetamido-3,4,6-tri-O-acetyl-2-deoxy-β-Dglucopyranosyl)- 5-(1-benzyl-1H-indol-2-yl)-1,3,4-oxadiazole-2(3H)-thione BnN-5A has been investigated. In vitro treatment of hepatic α-amylase and β-glucuronidase from control and streptozotocin-induced diabetic rats by S- and Nglycosyl analogues from oxadiazolinethione derivatives exhibited a significant dose-dependent decrease on the specific activity of both α-amylase and β-glucuronidase. Moreover, these compounds also exhibited a significant decrease on the specific activity of α-amylase and α-glucosidase produced by Bacillus subtilis AH. The observed IC50 values of these compounds are much lower than that of ethanolamines, higher for α-glucosidase than α-amylase from bacteria and significantly lower for hepatic α-amylase and β-glucuronidase from diabetic rats. The obtained results suggest that these compounds are good inhibitors that act on glycosidases from bacteria and normal / diabetic rats in different mechanisms.