Process for preparing 5-(pyridinyl)benzoxazol-2(3H)-ones

Abstract

5-PY-benzoxazol-2(3H)-ones, cardiotonic agents, are prepared by reacting 2-amino-4-PY-phenol with a carbonylating agent, e.g., carbonyldiimidazole, where PY is 4- or 3-pyridinyl or 4- or 3-pyridinyl having one or two lower-alkyl substituents. 5-PY-benzoxazol-2(3H)-ones or pharmaceutically-acceptable acid-addition or cationic salts thereof are disclosed as active components in cardiotonic compositions for increasing cardiac contractility and in the method for increasing cardiac contractility in a patient requiring such treatment.

Dependencies are inferred from the claim text.