Disclosed is a compound which is useful as an AMPK activator. A compound represented by formula: or a pharmaceutically acceptable salt thereof, wherein R 4 is hydrogen, or substituted or unsubstituted alkyl, R 1 , R 2 and R 3 are each independently hydrogen, halogen, hydroxy, cyano, nitro, carboxy, substituted or unsubstituted alkyl or the like, with the proviso that R 1 , R 2 and R 3 are not simultaneously hydrogen, X is a single bond, -S-, -O-, -NR 5 -, -C(=O)- or the like, R 5 is hydrogen, or substituted or unsubstituted alkyl, Y is substituted or unsubstituted cycloalkyl, substituted or unsubstituted cycloalkenyl, substituted or unsubstituted heterocyclyl or the like.
