Recyclization in the series of spiro[indole-3,5′-pyrimido[4,5-b] quinoline]-2,2′,4′-triones prepared by a three-component reaction of isatins with (thio)barbituric acids and electron-rich anilines

Abstract

A ring-ring transformation in the series of spiro[indole-3,5′- pyrimido[4,5-b]quinoline]-2,2′,4′-trione derivatives prepared by a three-component reaction of (thio)barbituric acids, electron-rich aromatic amines, and isatins was observed. © Georg Thieme Verlag Stuttgart - New York.