A convenient two-step method is developed for the preparation of benzo[g]benzothiazolo[2,3-b]quinazoline-7,12-quinones from 2-acylnaphthohydroquinones and 2-aminobenzothiazoles. The structure of the heterocyclic quinones is supported by X-ray crystallography. This protocol provides an operationally simple strategy to prepare the title compounds and shows good functional flexibility and easily available starting materials. Evidences are reported on the significant in vitro antiproliferative activities of some of the obtained heterocyclic quinones on prostate, bladder, and breast human-derived tumor cell lines.