Synthesis of Bioactive 3,4-Dihydro-2H-naphtho[2,3-b][1,4]oxazine-5,10-dione and 2,3,4,5-Tetrahydro-1H-naphtho[2,3-b]azepine-6,11-dione Derivatives via the Copper-Catalyzed Intramolecular Coupling Reaction

A convenient synthesis of 3,4-dihydro-2 H-naphtho[2,3- b][1,4]oxazine-5,10-diones and 2,3,4,5-tetrahydro-1 H-naphtho[2,3- b]azepine-6,11-diones via the copper-catalyzed intramolecular C-O/C-C coupling reaction is described. This method showed a good tolerance for functional groups and was applied to the synthesis of natural product core structures. Some coupling products exhibited moderate activities against lung cancer A549 cells.