The invention relates to novel cholecystokinin antagonists of the formula ##STR1## wherein R.sup.1 is aryl which may have suitable substituent(s), X is --O-- or ##STR2## in which R.sup.3 is hydrogen or lower alkyl, A is bond; or methylene, ethylene, trimethylene, tetramethylene, pentamethylene or hexamethylene, each of which may have lower alkyl group(s), andR.sup.2 is heterocyclic(C.sub.3 -C.sub.6) alkenoyl or heterocycliciccarbonyl, or a pharmaceutically acceptable salt thereof, useful as a cholecystokinin antagonist.