New Method for the Synthesis of 1-Substituted (3a,6a)-Diaryl­glycolurils

A new approach has been developed for the synthesis of 1-substituted 3а,6а-diarylglycolurils from an imidazolone, imidazo­oxazolone, imidazooxazinone, or imidazooxazepinone and urea in the presence of hydrochloric acid. The structure of 1-ethyl-3а,6а-diphenylglycoluril was confirmed by X-ray diffraction studies. © Georg Thieme VerlagStuttgart · New York.