Isolation and structure of combretastatin

Abstract
The South African tree Combretumcaffrum has been shown to contain a constituent capable of significantly reversing astrocyte formation employing the National Cancer Institute's 9ASK system. The constituent responsible for astrocyte reversal was isolated and designated combretastatin (1). Structural elucidation was initiated employing spectral methods and completed by X-ray crystallographic analysis. By this means combretastatin was assigned structure 1. Further biological evaluation and a total synthesis are now in progress.