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 pyrrolo[1,2-a]quinoxalin-4(5H)-one derivatives as novel non-covalent Bruton's tyrosine kinase (BTK) inhibitors.

Bruton's tyrosine kinase (BTK) is a promising target in the treatment of B cell malignancies and autoimmune disorders. Developing selective non-covalent BTK inhibitors is an important strategy to overcome the side effects and drug resistance induced by covalent BTK inhibitors. In this article, we designed and synthesized pyrrolo[1,2-a]quinoxalin-4(5H)-one and imidazo[1,2-a]quinoxalin-4(5H)-one based selective noncovalent BTK inhibitors via scaffold hopping from BMS-986142 and investigated their biological activities. Among the synthesized compounds, pyrrolo[1,2-a]quinoxalin-4(5H)-one derivatives 2 and 4 showed great BTK inhibition potency with IC50 value at 7.41 nM and 11.4 nM, respectively. Besides, they showed equivalent or even better potency in U937 and Ramos cells than BMS-986142. The kinase selectivity profiling study illustrated the excellent selectivity of compound 2 against a panel of 468 kinases. In U937 xenograft models, compound 2 could significantly inhibit tumor growth with TGI = 65.61%. In all, we provided a new scaffold as non-covalent selective BTK inhibitors and the representative compounds exhibited potency both in vitro and in vivo.

Discovery of Pteridine-7(8H)-one Derivatives as Potent and Selective Inhibitors of Bruton's Tyrosine Kinase (BTK).

Bruton's tyrosine kinase (BTK) is an attractive therapeutic target in the treatment of cancer, inflammation, and autoimmune diseases. Covalent and noncovalent BTK inhibitors have been developed, among which covalent BTK inhibitors have shown great clinical efficacy. However, some of them could produce adverse effects, such as diarrhea, rash, and platelet dysfunction, which are associated with the off-target inhibition of ITK and EGFR. In this study, we disclosed a series of pteridine-7(8H)-one derivatives as potent and selective covalent BTK inhibitors, which were optimized from 3z, an EGFR inhibitor previously reported by our group. Among them, compound 24a exhibited great BTK inhibition activity (IC50 = 4.0 nM) and high selectivity in both enzymatic (ITK >250-fold, EGFR >2500-fold) and cellular levels (ITK >227-fold, EGFR 27-fold). In U-937 xenograft models, 24a significantly inhibited tumor growth (TGI = 57.85%) at a 50 mg/kg dosage. Accordingly, 24a is a new BTK inhibitor worthy of further development.

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.