Synthesis of a 6H-Pyrazolo[4,5,1-de]acridin-6-one Derivative: A Useful Intermediate of Antitumour Agents

A 6H-pyrazolo[4,5,1-de]acridin-6-one derivative, a useful intermediate of antitumor agents, was prepared by a facile synthetic route from 2-bromobenzoic acid and 6-nitroindazole involving a halogenocopper(I)-catalyzed Ullmann coupling reaction and Friedel-Crafts cyclization.