Patent ID: 7750150

Claim:
A method for preparing a monohydrochloride acid addition salt of a piperazine derivative or a water adduct of said monohydrochloride acid addition salt comprising: reacting a piperazine derivative with an acid salt of pyridine thus forming a monohydrochloride acid addition salt of said piperazine derivative; wherein said piperazine derivative is characterized by formula (I): wherein X represents —NH—, Y 1 , Y 2 and Y 3 each independently represent a hydrogen or halogen atom or a lower alkyl or lower haloalkyl group, R 1 , R 2 and R 3 each independently represent a hydrogen or halogen atom or a lower alkyl, lower haloalkyl, lower alkylthio, lower haloalkoxy or lower alkoxyalkoxy group, 1 denotes an integer of from 1 to 2, m denotes an integer of from 2 to 4, and n denotes an integer of from 1 to 3.