In Vivo: α-Glucosidase-IN-16 (compound 13B) (10 and 20 mg/kg; PO; once daily for 28 days) significantly reduces the level of blood glucose in diabetic rats. α-Glucosidase-IN-16 (2000 mg/kg; PO; single dosage) exhibits no toxic effects in mice. α-Glucosidase-IN-16 (10 and 20 mg/kg; PO; single dosage) significantly reduces serum glucose level after glucose administration in rats.