A styrylquinazoline derivative that acts as a p53 stabilizing agent. It not only restores p53 functions in mutant p53-expressing cells but can also significantly increase the protein level and promote the activity of wild-type p53 in multiple human cancer cell lines, leading to cell cycle arrest or apoptosis. CP-31398 enhances the protein levels of wild-type p53 by blockade of ubiquitination and degradation of p53 without interrupting the physical association between p53 and MDM2 in vivo. MW: 435.39. Purity ≥98% by TLC