Divergent synthesis of pyrrolidone fused pyrimido[1,2-b]indazole through selective trapping of an enone intermediate by 1H-indazol-3-amine

An oxidant-controlled divergent synthesis of a pyrrolidone fused pyrimido[1,2- b ]indazole skeleton was developed through selective cyclization of an in situ generated enone intermediate and 1 H -indazol-3-amine.