GAMMA-PYRONE COMPOUNDS AS POTENTIAL ANTICANCER DRUGS

The gamma-pyrones, artomunoxanthotrione epoxide, cyclocommunol, cyclom ulberrin, and cyclocommunin exhibited potent inhibition of human PLC/P RF/5 and KB cells in-vitro. Dihydroisocycloartomunin showed significan t and potent inhibition of human PLC/PRF/5 and KB cells in-vitro, resp ectively. Cyclomorusin, dihydrocycloartomunin and artomunoxanthone sho wed significant inhibition of KB cells in-vitro. Based on the above fi nding and the reported antileukaemic activity of xanthone psorospermin , a series of natural gamma-pyrones was prepared and the inhibition of human PLC/PRF/5 and KB cells in-vitro was measured. Structure-activit y analysis indicated the epoxide group substituted at 3-hydroxyl and 2 ,6-; 3,6-; and 3,5-dihydroxyl xanthone enhanced the anti-tumour activi ty. The epoxide group substituted at the 6-hydroxyl group of 1,6-dihyd roxyxanthone did not show anti-tumour activity.