Synthesis and molecular docking studies of imines as α-glucosidase and α-amylase inhibitors

Imine functionality is found in many compounds with important biological activity. Thus, the development of novel synthetic approaches for imines is important. In this work, it is propose an easy, eco-friendly and straightforward synthesis pathway of aryl imines under microwave irradiation catalyzed by Alumina-sulfuric acid. In addition, the in vitro enzymatic inhibition, antioxidant activity and molecular docking studies were performed. The aryl imines were isolated with yields in the range of 37-94%. All aryl imines synthesized were evaluated for in vitro inhibitory potential against alpha-glucosidase and alpha-amylase enzymes and the results exhibited that the most of the compounds displayed inhibitory activity against both enzymes. The (E)-1-(4-nitrophenyl)-N(pyridin-2-yl)methanimine (3d) was 1.15-fold more active than acarbose against a-amylase whilst the (E)-1-phenyl-N-(pyridin-2-yl)methanimine (3c) displayed similar activity that acarbose against alpha-glucosidase. The molecular docking studies in a-glucosidase and alpha-amylase reveal that aryl imines mainly establish an H-bond with the R-2-subtituent and hydrophobic interactions with the R-1-subtituent. The docking analysis reveals these synthetic aryl imines 3d-i interact in same active site than acarbose drug in both enzymes.