Synthesis and biological activities of metabolites of mosapride, a new gastroprokinetic agent.

In order to confirm the proposed structures of two metabolites 3 and 4 of the gastroprokinetic agent mosapride [4-amino-5-chloro-2-ethoxy-N-([4-(4-fluorobenzyl)-2-morpholinyl] methyl)benzamide, 2], the compounds were synthesized and their biological activity was examined. The structures of the metabolites were confirmed by means of comparison with the synthetic compounds. The serotonin 5-HT4 receptor agonistic activities of the metabolites were found to be less than that of mosapride.