Potential cancer chemopreventive activity of simple isoquinolines, 1-benzylisoquinolines, and protoberberines

Several types of isoquinoline alkaloids were tested for their inhibitory activities against Epstein-Barr virus early antigen activation induced by 12-O-tetradecanoyl-phorbol-13-acetate in Raji cells. In addition, these alkaloids were evaluated with respect to their ability to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radicals. The results suggest that some of these isoquinoline alkaloids might be valuable as potential cancer chemopreventive agents. For both tests, structure-activity relationships are discussed.