The present invention addresses the problem of providing a compound represented by formula (1) or a salt thereof, which is effective as a bactericide for agricultural and horticultural use. In the formula, R1 represents a hydroxyl group, a cyano group or the like； each of R2, R3 and R4 independently represents a hydrogen atom, a halogen atom or the like； R5 represents a hydrogen atom, a halogen atom or the like； X represents an oxygen atom or a sulfur atom； Y represents a phenyl group, a pyridyl group or the like； and the bond including a broken line part represents a double bond or a single bond.
