Piperazine compound represented by the formula (I) or salt thereof, ** Formula ** in which X represents CH or an N atom； R1 represents C1-6 alkyl； R2 represents C1-6 alkyl which may have 1, 2 or 3 substituents, C2-6 alkenyl which may have 1, 2 or 3 substituents, - (C>； = O) -N (R3) (R4), or - (C>； = O) -OR5, R3 and R4 are the same or different, and each represents hydrogen or C1-6 alkyl which may have 1, 2 or 3 substituents； or R3 and R4 taken together with a nitrogen atom to which R3 and R4 are attached, can form a saturated heterocyclic group； and R5 represents hydrogen or C1-6 alkyl which may have 1, 2 or 3 substituents or aralkyl； wherein the substituents are selected from the group consisting of halogen, hydroxyl, cyano, nitro, alkyl, halogenoalkyl, cycloalkyl, cycloalkyl-alkyl, aralkyl, alkenyl, alkynyl, alkoxy, halogenoalkoxy, cycloalkoxy, cycloalkyl-alkoxy, aralkyloxy, alkylthio, cycloalkyl-alkylthio, amino, mono- or di-alkylamino, cycloalkyl-alkylamino, acyl, acyloxy, oxo, carboxyl, alkoxycarbonyl, aralkyloxycarbonyl, carbamoyl, saturated or unsaturated heterocyclic groups, aromatic hydrocarbon and a saturated heterocycloxy group.Compuesto de piperazina representado por la fórmula (I) o sal del mismo, **Fórmula** en el que X representa CH o un átomo de N； R1 representa alquilo de C1-6； R2 representa alquilo de C1-6 que puede presentar 1, 2 o 3 sustituyentes, alquenilo de C2-6 que puede presentar 1, 2 o 3 sustituyentes, -(C>；=O)-N(R3)(R4), o -(C>；=O)-OR5, R3 y R4 son iguales o diferentes, y cada uno representa hidrógeno o alquilo de C1-6 que puede presentar 1, 2 o 3 sustituyentes； o R3 y R4 tomados junto con un átomo de nitrógeno al que R3 y R4 están unidos, pueden formar un grupo heterocíclico saturado； y R5 representa hidrógeno o a lquilo de C1-6 que puede presentar 1, 2 o 3 sustituyentes o aralquilo； en el que los sustituyentes se seleccionan de entre el grupo que consiste en halógeno, hidroxilo, ciano, nitro, alquilo, halogenoalquilo, cicloalquil
