Antibacterial activity of maytenonic acid isolated from the root-bark of Maytenus senegalensis

Maytenus senegalensis is an important medicinal plant in East Africa. Methanolic extracts of the root-bark exhibit antibacterial activity. The isolation of the antibacterial compound, 3-oxo-friedelan-20α-oic acid, more commonly known as maytenonic acid, from the root-bark of M. senegalensis is described herein. This compound was first described in 1971 but the structure was not completely settled upon. The configuration at C-20 was corrected on the basis of chemical transformation and X-ray data of its methyl ester. Using improved NMR techniques a full set of spectral data for this compound is now given and configuration at C-20 confirmed by NOE contacts observed in 2D-ROESY spectrum.