A variety of different natural combretastatin molecules are present in the bark of C. afrum, commonly known as South African Bush Willow.
Of the natural products presently known combretastatin A-4 is the most potent in regards to both tubulin binding ability and cytotoxicity.
[3] Members of the combretastatin family possess varying ability to cause vascular disruption in tumors.
Endothelial cells treated with combretastatin rapidly balloon in shape causing a variety of effects which result in necrosis of the tumor core.
One reasonably easy synthesis is as follows: To directly generate the cis forms a Perkin condensation reaction can be used.