Exploring Novel PLK1 Inhibitors based on Computational Studies of2,4-Diarylaminopyrimidine Derivatives

Background: Polo-like kinase 1 (PLK1) is an important target for anti-cancer drugs. A series of novel 2,4-diarylaminopyrimidine derivatives (DAPDs) as PLK1 inhibitors (PLKIs) with remarkable activities have been reported recently. Methods: A systemically computational study was performed on these DAPDs, including threedimensional quantitative structure-activity relationship (3D-QSAR) modeling, molecular docking, and molecular dynamics (MD) simulation. Results: The constructed 3D-QSAR models exhibited reliable predictability with satisfactory validation parameters. The dockings revealed the binding modes of DAPDs in PLK1 protein, and two key residue, Cys133 and Phe183, could interact with DAPDs by hydrogen bonds and π-π stacking, which might be significant for the activity of these PLKIs. Eight compounds with higher predicted activity than the most active DAPD-compound (16) were designed based on the 3D-QSAR models. These newly designed compounds also exhibited higher docking scores than compound 16 in the binding pocket of PLK1. The ADME predictions and MD simulations further indicated that two hit compounds with reasonable pharmacokinetics properties could stably bind with PLK1 and have the potential to become novel PLKIs. Conclusion: Two newly designed compounds might have the potential to be novel PLKIs. These results might provide important information for the design and development of novel PLKIs.