A compound represented by general formula (I), a pharmaceutically acceptable salt thereof, or a solvate of the compound or salt has an Aβ production inhibitory activity or BACE 1 inhibitory activity, and is thus useful as an agent for treating neurodegenerative diseases caused by Aβ as typified by Alzheimer's disease.(In the formula, ring A represents a C6-14 aryl group or the like； L represents -NRLCO- (wherein RL represents a hydrogen atom or the like) or the like； ring B represents a C6-14 aryl group or the like； X represents a C1-3 alkylene group or the like； Y represents a C1-3 alkylene group or the like； Z represents an oxygen atom or the like； R1 and R2 each independently represents a hydrogen atom or the like； and R3, R4, R5 and R6 each independently represents a hydrogen atom, a halogen atom or the like.)
