Discovery and Structural Optimization of N5-Substituted 6,7-Dioxo-6,7-dihydropteridines as Potent and Selective Epidermal Growth Factor Receptor (EGFR) Inhibitors against L858R/T790M Resistance Mutation.
Hao Y, Wang X, Zhang T, Sun D, Tong Y, Xu Y, Chen H, Tong L, Zhu L, Zhao Z, Chen Z, Ding J, Xie H, Xu Y, Li H.
EGFR-targeted inhibitors (gefitinib and erlotinib) provided an effective strategy for the treatment of non-small-cell lung cancer. However, the EGFR T790M secondary mutation has become a leading cause of clinically acquired resistance to these agents. Herein, on the basis of the previously reported irreversible EGFR inhibitor (compound 9), we present a structure-based design approach, which is rationalized via analyzing its binding model and comparing the differences of gatekeeper pocket between the T790M mutant and wild-type (WT) EGFR kinases. Guided by these results, a novel 6,7-dioxo-6,7-dihydropteridine scaffold was discovered and hydrophobic modifications at N5-position were conducted to strengthen nonpolar contacts and improve mutant selectivity over EGFR(WT). Finally, the most representative compound 17d was identified. This work demonstrates the power of structure-based strategy in discovering lead compounds and provides molecular insights into the selectivity of EGFR(L858R/T790M) over EGFR(WT), which may play an important role in designing new classes of mutant-selective EGFR inhibitors.