The p53-MDM2 interaction has been proved to,, be a valuable target, to develop effective antitumor agents. Novel p53-MDM2 inhibitors bearing pyrrolidone scaffolds were successfully identified by structure-based design. The nanomolar inhibitor 5 possessed good p53-MDM2 inhibitory activity (K-i = 780 nM) due to its hydrophobic and hydrogen bonding interactions with MDM2. Further hit optimization led to. the discovery of a number of highly potent pyrrolidone derivative's with improved p537-MDM2 inhibitory activity and in vitro antiproliferative potency. Compounds 41 (K-i = 260.0 nM) and 60a (K-i = 150.0 nM) showed good and selective activity against tumor cells with deleted p53. In addition, these two Compounds also :effectively inhibited the tumor growth in the A549 xenograft model: Interestingly, compound 41 was proved to be a potent MDM2/MDMX dual inhibitor. The novel pyrrolidone p53-MDM2 inhibitors represent promising lead structures for the development Of novel antitumor agents.
Design, synthesis and structure–activity relationship of 4,5-dihydropyrrolo[3,4- c ]pyrazol-6(1 H )-ones as potent p53-MDM2 inhibitors
pyrrolo[3,4-c]pyrazol-6(1H)-ones were found to be potent p53-MDM2 inhibitors. Further optimization and structure–activity relationship studies were described in the present work. The result revealed that benzyl group on position N1 of imidazole and bromine on C4-phenyl of pyrrolidone showed higher inhibitory activities. In vitro antiproliferative assay demonstrated the potent p53-MDM2 inhibitor 5c with