Cytotoxicity of natural compounds isolated from the seeds of Garcinia afzelii.

The new compounds guttiferone O (1) and 3-methoxycheffouxanthone (2) have been isolated from the seeds of Garcinia afzelii Engl., together with nine known compounds: 2-hydroxy-1,7-dimethoxyxanthone (3), smeathxanthone A (4), 1,5-dihydroxyxanthone (5), 1,6-dihydroxy-5-methoxyxanthone (6), cheffouxanthone (7), 1,3,5-trihydroxyxanthone (8), smeathxanthone B (9), isoxanthochymol (10) and guttiferone E (11). Their structures were elucidated by means of 1D and 2D-NMR techniques. All the isolates showed high cytotoxic activity and were found inactive when tested against HIV and influenza viruses.