Synthesis and in vitro antitumor activity of phenanthrolin-7-one derivatives, analogues of the marine pyridoacridine alkaloids ascididemin and meridine: Structure-activity relationship

A series of substituted pyrido[4,3,2-de][1,7] or [1,10]-phenanthrolin-7-ones, analogues of the marine pyridoacridines meridine and ascididemin, have been synthesized on the basis of Diels-Alder reactions involving different quinoline-5,8-diones and N,N-aldehyde-dimethylhydrazones. All the compounds were evaluated for in vitro cytotoxic activity against 12 distinct human cancer cell lines. They all exhibit cytotoxic activity with IC 50 values at least of micromolar order.