Provided is a nitrogen-containing heterocyclic derivative having a 2-imino group, which is represented by the following Formula (I). [in the formula, Ar represents a phenyl group which may be substituted, a 5- to 6-membered heterocycle which may be substituted, or a 4- to 10-membered heterocycloalkyl group, A represents a heterocycle having a 5- to 10-membered unsaturated bond including one or more nitrogen atoms, and has an imino group substituted with an R group at a position adj acent to the nitrogen atom present on the cycle, Y represents a hydrogen atom, a halogen atom, a hydroxyl group, a C1 to C6 alkyl group which may be substituted with a halogen atom, a C1 to C6 alkyloxy group which may be substituted with a halogen atom, a cyano group, or a nitro group, and R represents any one of groups represented by the following Formulae (a) to (e), (y) or (z).]
