Design, synthesis and biological evaluation of 2,4,5-trisubstituted 7H-Pyrrolo[2,3-d]pyrimidine derivatives as potent EGFR tyrosine kinase inhibitors against the C797S acquired resistance mutation.

The C797S mutation in the epidermal growth factor receptor (EGFR) presents a significant challenge in treating non-small cell lung cancer (NSCLC), as it confers resistance to osimertinib. To tackle this issue, we designed and synthesized novel 7H-pyrrolo[2,3-d]pyrimidine derivatives that bind to the EGFR kinase domain in the presence of the C797S mutation. The representative compound cis-32 (LN-B72) not only showed remarkable kinase inhibitory activity against EGFRDel19/T790M/C797S and EGFRL858R/T790M/C797S mutants, with IC50 values of 8.7 nM and 7.9 nM, respectively, but also displayed potent antiproliferative activity, achieving IC50 values of 0.046 μM and 0.060 μM in corresponding mutant cell models. Furthermore, LN-B72 exhibited broad-spectrum inhibitory activity against EGFR mutants, including those harboring Exon 20 insertion mutations. Mechanistic studies indicated that LN-B72 disrupted the EGFR signaling pathway by preventing the phosphorylation of key downstream proteins. In vivo antitumor activity studies demonstrated that LN-B72 significantly inhibited tumor growth. This work establishes a promising foundation for developing novel therapeutic strategies targeting NSCLC patients with the C797S mutation.