Novel 1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-ones having an aryl or heteroaryl group in the 6-position, useful as phosphodiesterase inhibitors, are prepared by reacting a 2-amino-5-(aryl or heteroaryl)pyridine-3-carboxylic acid with diphenylphosphoryl azide. The compounds are of the formula ##STR1## where R.sub.1 and R.sub.3 are hydrogen or lower-alkyl, R.sub.5 is lower-alkyl or fluorinated lower-alkyl, and Ar is 4- or 3-pyridinyl, or phenyl or substituted phenyl.
具有芳基或杂环芳基在6位的新型1,3-二氢-
2H-咪唑[4,5-b]
吡啶-2-酮,可用作
磷酸二酯酶抑制剂,通过将2-
氨基-5-(芳基或杂环芳基)
吡啶-3-
羧酸与二苯基
磷酰胺反应制备。所述化合物的
化学式为##STR1##
其中,R.sub.1和R.sub.3为氢或低碳基,R.sub.5为低碳基或
氟代低碳基,Ar为4-或3-
吡啶基,苯基或取代苯基。