There is provided a novel and efficent method of synthesizing 7,10-dihydro-6,11-dihydroxy-5,9,12(8H)-naphthacenetrione and analogs thereof substituted in the 1,2,3 or 4 positions. The novel method comprises reacting the appropriate quinizarinquinone with a haloprene under Diels-Alder conditions, followed by aromatization and treatment with strong acid under very mild temperature conditions. The products of this process are important intermediates in the synthesis of daunomycin and its analogs which are useful in the therapy of neoplastic ailments.