Treating gastro-intestinal disorders and emesis with n-(heterocyclic substituted) benzamides

Compounds of the formula (I), and their pharmaceutically acceptable salts: (I) wherein: R1 is a C1-6 alkoxy group; R2 and R3 are the same or different and are hydrogen, halogen, CF3, hydroxy, C1-6 alkoxy, C2-7 acyl, amino, amino substituted by one or two C1-6 alkyl groups, C2-7 acylamino aminocarbonyl or aminosulphone optionally substituted by one or two C1-6 alkyl groups, C1-6 alkylsulphone or nitro groups; X is either a nitrogen atom, in which case m+n is 3 to 5, m is 2 to 4, n is 1 to 3; or X is CH in which case m+n is 2 to 5, m is 1 to 5, and n is 0 to 4; p is 0 to 3; R4 is hydrogen, C1-6 alkyl, phenyl or phenyl-C1-6 alkyl, either of which phenyl moiety may be substituted by C1-6 alkyl, C1-6 alkoxy, CF3 or halogen, and R5 is hydrogen; or R4 and R5 are attached to two adjacent carbon atoms and form together with these two carbon atoms a fused benzene ring, which benzene ring may be substituted by C1-6 alkyl, C1-6 alkoxy, CF3 or halogen; are useful for treating disorders of the gastro-intestional function and for treating emesis.