Structural modifications of anguidin and antitumor activities of its analogues.
Approximately 60 derivatives of anguidin were prepared for evaluation of antitumor activities. Positions 3, 4, 8-10, and 15 were modified, and the resultant derivatives were screened against P-388 leukemia. It was found that introduction of the C3-keto and C3,C8-diketo groups markedly improved the antileukemic activity, whereas epoxidation of the C9-C10 double bond or oxidation of the C15 position diminished its activity. Selected derivatives were further tested in the L1210, B16, Lewis lung, Colon 36, and Colon 38 tumor lines. Among these compounds, 4 beta, 15-diacetoxyscirpene-3,8-dione (54) and 4 beta-(chloroacetoxy)-15-acetoxyscirpene-3,8-dione (55) were found to be most active in various tumors. Inhibitory action of several analogues on protein synthesis was also examined using H-HeLa cells.