A new series of N-arylalkylaminoquercitols were synthesized by reductive amination of aminoquercitol bisacetonide 5 and a variety of aryl aldehydes. The targeted N-substituted aminoquercitols having phenolic moiety (7a-7c) displayed significantly enhanced α-glucosidase inhibition, which is 26-32 times more potent than that of the unmodified aminoquercitol 6. In addition, compounds 7a-7c also retained antioxidant activity with relatively more pronounced potency than their original phenolics. This recent finding suggests an approach to develop effective antidiabetic agents by incorporating antioxidative moiety into aminocyclitol core structure.