This invention provides compounds of the formula (I) and (II): or the pharmaceutically acceptable esters thereof, and the pharmaceutically acceptable salts thereof: wherein R1 is hydrogen or halo; R2 and R3 are independently hydrogen or C1-6 alkyl; R4 and R5 are independently hydrogen or C1-6 alkyl; R6 is hydrogen, C1-12 alkyl, C1-6 alkoxy (C1-6)alkyl or C1-12 alkyl substituted by up to 3 substituents selected from the groups consisting of C3-8 cycloalkyl, aryl, heteroaryl and heterocyclic; R7 and R8 are hydrogen or taken together may form alkylene chain having one or two carbon atoms; R9 is C1-6 alkyl or C3-8 cycloalkyl; R10 is C1-6 alkyl or NR11R12; L is (CR11R12)n or NR11; M is NR11 or (CR11R12)n; R11 and R12 are independently hydrogen or C1-6 alkyl; n is an integer from 0 to 5; and m is an integer from 0 to 2; said heterocyclic, aryl and heteroaryl are unsubstituted or are substituted by at least one substituent selected from the group consisting of halo and C1-6 alkyl; with the proviso that when R9 is C1-6 alkyl, L is not NR11. These compounds have 5-HT4 receptor binding activity, and thus are useful for the treatment of gastroesophageal reflux disease, non-ulcer dyspepsia, irritable bowel syndrome or the like in mammalian, especially humans. This invention also provides a pharmaceutical composition comprising the above compound.