Cancer preventive agents, Part 2: Synthesis and evaluation of 2-phenyl-4-quinolone and 9-oxo-9,10-dihydroacridine derivatives as novel antitumor promoters.

Abstract 2-Phenyl-4-quinolone and 9-oxo-9,10-dihydroacridine derivatives were synthesized and screened as potential antitumor promoters by examining the ability of the compounds to inhibit Epstein–Barr virus early antigen (EBV-EA) activation induced by the tumor promoter 12- O -tetradecanoylphorbol-13-acetate (TPA) in Raji cells. Interestingly, compounds 14 , 15 , and 17 showed similar inhibitory effects (89–92%, 66–69%, and 24–29% at 1000, 500, and 100 mol ratio to TPA, respectively) against EBV-EA with potencies comparable to those of glycyrrhetic acid, a known natural antitumor-promoter.