Provided is a compound represented by general formula (1) or a pharmaceutically-acceptable salt thereof. [In formula (1), R1 and R2 may be the same or different from each other, and each represents a hydrogen atom, a halogen atom, a hydroxy group, a carboxy group, a cyano group, or an optionally-substituted C1-6 alkyl group or the like； R3 represents a hydrogen atom； R4 represents an optionally-substituted 4- to 10-membered monocyclic heterocyclic group containing 1-4 heteroatoms selected from an oxygen atom, a nitrogen atom, and a sulfur atom； X represents a group represented by -CH2-, -CH2-CH2-, -CH2-CH2-CH2-, or -CH2-O-CH2-； and Z represents a hydrogen atom or a hydroxy group].本發明為關於一種下述一般式(1)所表示之化合物或其藥理學上所容許之鹽。 [式(1)中，R1及R2亦可相同亦可相異，各自表示氫原子、鹵原子、羥基、羧基、氰基、亦可經取代之C1-6烷基等；R3表示氫原子；R4表示亦可經取代之包含選自氧原子、氮原子及硫原子中1~4個雜原子之4~10員之單環式雜環基；X表示下述式：-CH2-、-CH2-CH2-、-CH2-CH2-CH2-、或 -CH2-O-CH2-所表示之基；Z表示氫原子或羥基]。
