Disclosed is a piperazine compound represented by general formula (I) or asalt thereof. [In the formula, R1repre-sents an alkyl group having 1 to 6 carbon atoms； R2 represents any oneselected from a hydroxy group, an alkyl group having 1 to6 carbon atoms which may have a substituent, a group -(C=O)-N(R3)(R4) and agroup -(C=O)-OR5； R3 and R4 may be the sameas or different from each other, and R3 and R4 independently represent ahydrogen atom or an alkyl group having 1 to 6 carbonatoms which may have a substituent, or R3, R4 and a nitrogen atom to which R3and R4 are bound may together form a saturatedheterocyclic group； R5 represents a hydrogen atom or an alkyl group having 1to 6 carbon atoms which may have a substituent；and n represents 1 or 2.]
