Design, synthesis, and biological evaluation of diphenyl ether substituted quinazolin-4-amine derivatives as potent EGFRL858R/T790M/C797S inhibitors.

Epidermal growth factor receptor (EGFR) is a validated target for non-small-cell lung cancer (NSCLC). However, the treatment for EGFR-C797S mutation induced by third-generation EGFR inhibitors remains a concern. Therefore, the development of the fourth-generation EGFR inhibitors to overcome the EGFR-C797S mutation has great potential for clinical treatment. In this article, we designed and synthesized a series of diphenyl ether substituted quinazolin-4-amine derivatives that simultaneously occupy the ATP binding pocket and the allosteric site of EGFR. Among the newly synthesized compounds, 9d displayed excellent kinase activity against EGFRL858R/T790M/C797S with an IC50 value of 0.005 µM, and exhibited anti-proliferation activity in BaF3-EGFRL858R/T790M/C797S cells with the IC50 value of 0.865 µM. Furthermore, 9d could suppress phosphorylation of EGFR and induce cell apoptosis and cycle arrest at G2 phase in a dose-dependent manner in BaF3-EGFRL858R/T790M/C797S cells. More importantly, 9d displayed significant antitumor effects in BaF3-EGFRL858R/T790M/C797S xenograft mouse model (30 mg/kg, TGI = 71.14 %). All the results indicated compound 9d might be a novel fourth-generation EGFR inhibitor for further development in overcoming the EGFR-C797S resistance mutation.

Discovery and optimization of 4-anilinoquinazoline derivatives spanning ATP binding site and allosteric site as effective EGFR-C797S inhibitors.

Epidermal growth factor receptor (EGFR) is an effective drug target for the treatment of non-small cell lung cancer (NSCLC). However, a tertiary point mutation (C797S) at the ATP binding pocket of the EGFR induces resistance to the third-generation EGFR inhibitors, due to the loss of covalent interaction with Cys797. Here, we designed a series of 4-anilinoquinazoline derivatives that simultaneously occupied the ATP binding pocket and the allosteric site. The newly-synthesized compounds displayed high potency against EGFR-C797S resistance mutation. Among them, compound 14d presented high anti-proliferative effect against BaF3-EGFRL858R/T790M/C797S (IC50 = 0.75 µM) and BaF3-EGFR19del/T790M/C797S (IC50 = 0.09 µM) cells. Moreover, 14d resulted in obvious inhibition activities against EGFR and its downstream signaling pathways in a dose-dependent manner in BaF3-EGFR19del/T790M/C797S cells. Finally, 14d significantly inhibited tumor growth in BaF3-EGFR19del/T790M/C797S xenograft model (30 mg/kg, TGI = 67.95%). These results demonstrated that 14d is a novel and effective EGFR-C797S inhibitor which spanning the ATP binding pocket and the allosteric site and effective both in vitro and in vivo.

Discovery of pyrido[3,4-b]indol-1-one derivatives as novel non-covalent Bruton's tyrosine kinase (BTK) inhibitors.

Bruton's tyrosine kinase (BTK) is an attractive target for the treatment of malignancy and inflammatory/autoimmune diseases. Most of the covalent BTK inhibitors would induce off-target side effects and drug resistance. To improve the drug safety of BTK inhibitors, non-covalent inhibitors have attracted more and more attention. We designed a series of novel pyrido[3,4-b]indol-1-one derivatives (N-A and N-B) via scaffold hopping from CGI-1746. The structure-activity relationship (SAR) of the newly-synthesized compounds was explored. The results showed that compounds 12 and 18 exhibited potent enzymatic potency against BTK with IC50 values of 0.22 µM and 0.19 µM, respectively. In lymphoma cell lines U-937 cells and Ramos cells, compounds 12 and 18 displayed comparative antiproliferative activity with Ibrutinib. Moreover, compound 12 induced G1-phase cell cycle arrest and apoptosis in U-937 cells. And it could effectively inhibit tumor growth in U-937 xenograft mouse model (TGI = 41.90% at 50 mg/kg). In all, the new pyrido[3,4-b]indol-1-one derivatives have the antitumor potency by BTK inhibition and were worthy of further exploration.