Synthesis of cinnamic acid amide derivatives and the biological evaluation of A-Glucosidase inhibitory activity

Diabetes mellitus is a chronic metabolic disease associated with increased risk factors for morbidity and mortality. The treatment of diabetes is by reduction in postprandial hyperglycaemia via the inhibition of a-glucosidase. The aim of this research is to determine the inhibition of a-glucosidase activity on the synthesized cinnamic acid amide derivatives. A series of cinnamic acid amide derivatives (1–8) were synthesized and evaluated for inhibitory activity against a-glucosidases such as maltose and sucrose based on the structure-activity relationships. Among the eight synthesized compounds, compounds 3 and 4 which contained two hydroxyl group at the meta and para position of the cinnamic acid structure, displayed the highest activity of a-glucosidases inhibition for both maltose and sucrose. These results suggested that cinnamic acid amide such as compound 3, caffeoyl benzylamide, and compound 4, caffeoyl cyclohexylmethylamide, may serve as a lead compound for the development of novel a-glucosidases inhibitors and can be useful for the treatment of diabetes mellitus and its complications.