Copper-catalyzed efficient synthesis of 5-arylindazolo[3,2-b]quinazolin-7(5H)-ones from 2-nitrobenzaldehydes

A novel and practical copper-catalyzed approach is developed for the preparation of 5-arylindazolo[3,2-b]quinazolin-7(5H)-ones. The 2-amino-N'-arylbenzohydrazide, which easily prepared by reaction of isatoic anhydride with arylhydrazine, through a condensation/intramolecular cyclization reacted by 2-nitrobenzaldehydes in the present of CuI to afford corresponding 5-arylindazolo[3,2-b]quinazolin-7(5H)-ones in good yields.