Histamine H.sub.1 -receptor antagonists of the formula: ##STR1## where R.sup.1 is hydrogen or alkyl; one of R.sub.2 and R.sup.3 is alkyl and the other is ##STR2## where R.sup.4 is pyridin-2-yl, pyridin-4-yl, thienyl, or phenyl, any of which is optionally substituted by a halo, alkyl of 1 to 6 carbon atoms, nitro, trifluoromethyl, hydroxy or alkoxy of 1 to 6 carbon atoms substituent; and R.sup.5 is pyridin-2-yl, pyridin-4-yl or phenyl, any of which is optionally substituted by a halo, alkyl of 1 to 6 carbon atoms, alkoxy of 1 to 6 carbon atoms, nitro or trifluoromethyl substituent.
化合物的组成式为:##STR1## 其中R.sup.1为氢或烷基;R.sub.2和R.sup.3中的一个为烷基,另一个为##STR2## 其中R.sup.4为
吡啶-2-基,
吡啶-4-基,
噻吩基或苯基,任何一个都可以选择性地被卤素,1至6个碳原子的烷基,硝基,三
氟甲基,羟基或1至6个碳原子的烷氧基取代;R.sup.5为
吡啶-2-基,
吡啶-4-基或苯基,任何一个都可以选择性地被卤素,1至6个碳原子的烷基,1至6个碳原子的烷氧基,硝基或三
氟甲基取代。