The purpose is to provide a compound that is useful as an MT1 and/or MT2 receptor agonist. A compound represented by formula (I) acts as an MT1 and/or MT2 receptor agonist and has low CNS migration and can therefore be used as an agent for the prevention and/or treatment of urinary incontinence, lower urinary tract symptoms, storage symptoms, and other such urological conditions. (In the formula, Y is N or CR1 R1, R3, R4 are H, halogen, or the like R2 is alkyl or the like R51, R52 are H, alkyl, or the like X is a bond, -NR11-, or -NR11-O- (R11 is H, alkyl, or the like) R6 is alkyl, cycloalkyl, or the like and R7, R8 are H, halogen, or the like.)
