A convenient regioselective synthesis of pyrano[3,2-b]acridones involving nucleophilic addition to benzyne

Article abstract of DOI:10.1016/S0040-4039(99)01424-0

Acridone 8 was prepared by the nucleophilic addition of aniline 4 to benzyne 5. Hydrolysis of the ester group, followed by cyclisation gave the acridone 8, which was subsequently converted to the pyrano[3,2-b]acridin-4-ones 11 and 17.