1-[(1-Substituted-4-piperidinyl)methyl]-4-piperidine derivative, process for producing the same, medicinal compositions containing the same and intermediates of these compounds
1- (1-SUBSTITUTED-4-PIPERIDINYL)METHYL]-4-PIPERIDINE DERIVATIVES, PROCESS FOR PRODUCING THE SAME, MEDICINAL COMPOSITIONS CONTAINING THE SAME AND INTERMEDIATES OF THESE COMPOUNDS