A series of 4-amino-5-chloro-2-methoxy-N-(piperidin-4-ylmethyl) benzamides with a polar substituent group at the 1-position of the piperidine ring was synthesized and evaluated for its effect on gastrointestinal motility. The benzoyl, phenylsulfonyl, and benzylsulfonyl derivatives accelerated gastric emptying and increased the frequency of defecation. One of them, 4-amino-N-[1-[3-(benzylsulfonyl) propyl] piperidin-4-ylmethyl]-5-chloro-2- ...