Zinc oxide-NP catalyzed direct indolation of in situ generated bioactive tryptanthrin

Abstract

A ZnO-NP catalyzed direct indolation of in situ generated tryptanthrin via C–H functionalization and C–C bond formation has been developed. This novel and greener approach has been effectively utilized to accomplish the synthesis of 6-hydroxy-6-(1H-indol-3-yl)indolo[2,1-b]quinazolin-12(6H)-one derivatives in good to excellent yields with high product selectivity. Besides the in situ approach, a direct indolation of tryptanthrin has also been developed.