Antimalarial activity of 1,4-epidioxy-bisabola-2,12-diene derivatives

1,4-Epidioxy-bisabola-2,12-diene (3) and aromatic hydroperoxides (4, 5) were prepared by photoxidation of gamma-curcumene (1). Reduction and esterification of 6 and 7 afforded compounds 9 to 10. All compounds were tested in vitro for antimalarial activity. The activity could not be increased significantly, compared with 3. The most active compounds, 3 and 9, did not show in vivo antimalarial activity in mice.