A compound represented by formula (1), or a salt thereof, is provided that is effective as a wood preservative. In the formula, R1 represents an optionally substituted C1-C6 alkyl group, a C1-C6 haloalkyl group, etc., R2 represents a halogen atom, an optionally substituted C1-C6 alkyl group, an optionally substituted C1-C6 alkoxy group, etc., R3 represents a hydrogen atom, a halogen atom, an optionally substituted C1-C6 alkyl group, etc., n represents an integer 0-5, X represents an oxygen atom or a sulfur atom, Y represents a phenyl group having a substituent in an ortho position, a pyridyl group and the bond that includes the dashed line represents a double bond or a single bond.
