The main purpose of the invention is to provide a novel aromatic heterocyclic derivative or a pharmaceutically acceptable salt thereof. Examples of the invention include aromatic heterocyclic derivatives represented by general formula [1] and pharmaceutically acceptable salts thereof.In formula [1], R1 represents phenyl optionally substituted with one or two groups selected from the group consisting of halogens ,as well as alkyls and alkoxys optionally substituted by halogens； R2 represents a hydrogen, an alkyl, cycloalkyl, or alkoxy optionally substituted by a halogen, or a heteroaryl optionally substituted by an alkyl； X represents CR3, and Y represents N or CR4, or X represents N, and Y represents CR4； and Z represents CR5 or N.
