We report on the design, synthesis, and in vitro evaluation of new quinoline-5,8-dione and hydroxynaphthoquinone derivatives. The synthesized compounds were evaluated for in vitro antimalarial activity against Plasmodium falciparum. Of the 15 compounds, 7a-c, 8a, 9b, 11, and 15 were effective in growth inhibition with IC(50) values of below 5 μM.