Discovery of 4-Amino and 4-Hydroxy-1-aroylindoles as Potent Tubulin Polymerization Inhibitors

1-Aroylindoline, 1-aroyl-1,2,3,4-tetrahydroquinoline, and 1-aroylindole derivatives were synthesized and evaluated for anticancer activity. The 4-amino and 4-hydroxy-1-aroylindoles 26 and 27 with IC 50 of 0.9 and 0.6 microM, respectively, exhibited antitubulin activity superior or comparable to that of colchicine and combretastatin A-4. They also showed antiproliferative activity with IC 50 of 0.3-5.4 nM in a set of human cancer cell lines.