A number of 8-anilino-6-aryl-3,4-dihydrophenanthridine-1,7,10(2H)-triones were synthesized to measure their halfwave potentials and assessed for their in vitro antiproliferative activity on a panel of a non-tumor fibroblast and four human-derived tumor cell lines, using the MTT assay. The SAR analysis indicates that the antiproliferative activity is strongly dependent on the electron-donor and inductive effects of methoxy and bromine substituents, inserted into the 8-anilino-6-arylphenanthridinequinone scaffold. Among the series, three members showed significant antiproliferative activity (0.58-5.78 μM).