Synthesis, inhibitory activities, and QSAR study of xanthone derivatives as alpha-glucosidase inhibitors

Xanthones and their derivatives have been reported to exhibit strong inhibitory activities toward alpha-glucosidase. To provide deep insight into the correlation between inhibitory activities and structures of xanthones, multiple linear regression (MLR) method was employed to establish QSAR models for 43 xanthone derivatives that have diverse structures. Among the 38 typical descriptors investigated, Hs (number of H-bond forming substituents), N(pi) (number of aromatic rings), and S (softness value) can be utilized to model the inhibitory activity. Thus, inhibitory activities of xanthone derivatives can be regulated by H-bond forming substituents, pi-stacking-forming aromatic rings and softness values on the xanthone skeleton. The accuracy and predictive power of the proposed QSAR model were verified by LOO validation, Y-randomization, and test group validation with newly synthesized xanthone derivatives.