Isolation and structure of the strong cell growth and tubulin inhibitor combretastatin A-4

Abstract
Summary The African treeCombretum caffrum (Combretaceae) has been found to contain a powerful inhibitor of tubulin polymerization (IC502–3 μM), the growth of murine lymphocytic leukemia (L 1210 and P 388 with ED50≈0.003 μM and human colon cancer cell lines [(e.g. LoVo (ED50=0.005 μg/ml), HT29 (ED50 0.02 μg/ml, Colo 205 (ED50=0.07 μg/ml), DLD-1 (ED50=0.005 μg/ml) and HCT-15 (ED50=0.0009 μg/ml)] designated combretastatin A-4 (1c). The structure assigned by spectral techniques was confirmed by synthesis.