A compound of the formula (I): ##STR1## wherein R.sub.1 is a hydrogen atom or lower alkyl; R.sub.2 is a lower alkoxy, lower alkylamino, lower cycloalkyl, optionally substituted phenyl or optionally substituted heterocyclic group; R.sub.3 is an optionally substituted phenyl; R.sub.4 is an optionally substituted phenyl, optionally substituted cycloalkyl, optionally substituted alkyl or optionally substituted heterocyclic group, or a pharmaceutically acceptable salt thereof, which has a high affinity for gastrin receptors and/or CCK-B receptors but not for CCK-A receptors, and is useful for treating diseases associated with gastrin receptors and/or CCK-B receptors without inducing the side effects associated with CCK-A receptors.
化合物的式子(I):##STR1## 其中,R.sub.1是氢原子或低烷基;R.sub.2是低烷氧基、低烷基
氨基、低环烷基、可选取代的苯基或可选取代的杂环基;R.sub.3是可选取代的苯基;R.sub.4是可选取代的苯基、可选取代的环烷基、可选取代的烷基或可选取代的杂环基,或其药学上可接受的盐。该化合物具有高亲和力的胃泌素受体和/或CCK-B受体,但不具有CCK-A受体的亲和力。它可用于治疗与胃泌素受体和/或CCK-B受体相关的疾病,而不会引起与CCK-A受体相关的副作用。