Isolation, Structure, and Synthesis of Combretastatin C-1

Article abstract of DOI:10.1021/jo00278a023

A new cell growth inhibitory (PS ED50 2.2 μg/mL) phenanthraquinone designated combretastatin C-1 (2) has been isolated from the African tree Combretum caffrum.The structure (2) assigned combretastatin C-1 was based on high-resolution mass and NMR spectral analyses and confirmed by total syntheses.Synthetic routes 5b -> 6b -> 2 and especially 5c -> 6c -> 2 proved to be quite practical.