A new series of pyrroloquinolinones bearing different alkylamino side chains were synthesized and evaluated as cytotoxic compounds against three different human tumor cell lines (HeLa, HL-60 and A431). Some compounds showed interesting antiproliferative activity, in particular against A431 cells. The compounds were tested for their ability to counteract topoisomerase II relaxation activity and the most interesting one (3c) was tested also against topoisomerase I, resulting a dual inhibitor. The molecular interactions between 3c and the intracellular targets were finally investigated through molecular modeling simulations.