A p53 stabilizing agent; increases active mutant p53 and p53 reporter gene expression without increasing total protein levels of p53 in H1299 lung cancer cells transfected with mutant p53; is cytotoxic to a panel of 12 human glioma cell lines expressing wild-type or mutant p53 (EC50s = 11.2-22.2 μM); decreases tumor growth in an A375.S2 melanoma mouse xenograft model and completely inhibits tumor growth in a DLD-1 colon cancer mouse xenograft model at 100 mg/kg; dietary administration suppresses lung adenocarcinoma formation in a mouse model of tobacco carcinogen-induced lung adenoma and adenocarcinoma formation at 50 and 100 ppm