The new N2, N4-diphenylpyridine-2,4-diamine deuterated derivatives as EGFR inhibitors to overcome C797S-mediated resistance.

A series of new deuterated and non-deuterated N2, N4-diphenylpyridine - 2,4-diamine derivatives were synthesized and evaluated as EGFR C797S-mediated resistance inhibitors. Most of these compounds exhibited potent antiproliferative activity against Baf3-EGFR L858R/T790M/C797S and Baf3-EGFR Del19/T790M/C797S cancel cell lines, with IC50 values in the nanomolar concentration range. Among them, compound 14l represented the most active compound with IC50 values of 8-11 nM. Interestingly, metabolic stability assay with rat liver microsomes indicated that the half-life of the deuterated derivative 14o was significantly increased compared to that of 14l. In xenograft mice models, 14o inhibited tumor growth with excellent inhibitory rate of 75.1 % at the dosage of 40 mg/kg, comparing 73.2 % of the TGI with its non-deuterated compound 14l, at a dosage of 80 mg/kg. Mechanism studies revealed that 14o was a potent EGFR L858R/T790M/C797S and EGFR Del19/T790M/C797S kinase inhibitor, which could downregulate the protein phosphorylation of EGFR and m-TOR signaling pathways, arrest cell cycle at G2/M phase by affecting the expression of CDC25C, and promote cell apoptosis by regulating the expression of cleaved caspase-3. In summary, 14o could serve as a promising deuterated compound for the development of highly efficient anticancer agents.

Synthesis and evaluation of sulfonamide derivatives targeting EGFR790M/L858R mutations and ALK rearrangement as anticancer agents.

Fourteen new compounds bearing sulfonamide groups that target EGFRT790M/L858R mutations and ALK rearrangement were synthesized and evaluated as dual-target tumor inhibitors. The study on the anti-proliferation activity on cancer cells showed that the sulfonamide derivative with pyrimidine nucleus had much better activities compared with those with quinazoline nucleus. Among them, compound 19e exhibited excellent activity against H1975 cancer cell lines (EGFRT790M/L858R high express) and H2228 cells (ALK rearrangement) with the IC50 values of 0.0215 µM and 0.011 µM, respectively. The ALK and EGFR kinase inhibition assays also provided similar results. Genotype selectivity of EGFR on kinase and cell level, cytotoxicity towards human normal cell lines and cell morphology assay implied that 19e had acceptable selectivity and low toxicity. In addition, the inhibitory activity of 19e on H1975 and H2228 cells cloning and its apoptosis-inducing effect on the two cell lines were studied, and its inhibitory effect on the invasion and migration of tumor cells were also investigated. All the results show that 19e is worthy of further study.

The synthesis and evaluation of novel ALK inhibitors containing the sulfoxide structure.

With ceritinib as the lead, a series of novel compounds containing the sulfoxide structure were synthesized and evaluated as anaplastic lymphoma kinase inhibitors. Among them, compounds 18a-d exhibited excellent anti-proliferation activities on H2228 EML4-ALK cancer cell lines with 14-28 nM of the IC50 values. In xenograft mouse models, 18a-d inhibited tumor growth with an excellent inhibitory rate of 75.0% to 86.0% at the dosage of 20 mg kg-1 as compared to 72.0% of the reference ceritinib. Using 18d as a representative, which exhibited the best in vivo results, we carried out mechanistic studies such as anti-colony formation, induced tumor cell apoptosis, ALK kinase protein phosphorylation in H2228 tumor cells, and molecular docking. All these results indicate that compound 18d is a good anti-tumor lead compound and worthy of further study.

Discovery of new cyclopropane sulfonamide derivatives as EGFR inhibitors to overcome C797S-mediated resistance and EGFR double mutation.

The C797S mutation of EGFR leads to Osimertinib resistance by blocking the covalent binding of Cys797. To develop new agents that can overcome EGFR mutation resistance, thirty seven new cyclopropane sulfonamide derivatives were synthesized and evaluated as EGFRL858R/T790M/C797S or EGFRDel19/T790M/C797S inhibitors by structure-based screening. Most of the synthesized compounds exhibit good to excellent anti proliferation activity against to BaF3-EGFR L858R/T790M/C797S and BaF3-C797S/Del19/T790M cancer cell lines. Representative compounds 8l showed inhibitory activity against the two cancer cell lines with the IC50 values of 0.0012 and 0.0013 µM, respectively. Another compound 8h, exhibited slightly lower activity (0.0042 and 0.0034 µM of the IC50 values) to both of the two tri-mutation cell lines, but excellent activities against H1975 and PC9 cells with IC50 values of 13 and 19 nM, respectively. Considering the acquired drug resistance of tumors is a gradual process, we chose 8h for further in vivo and mechanism study. 8h was demonstrated significantly inhibited tumor growth with 72.1 % of the TGI in the BaF3/EGFR-TM xenograft tumor model and 83.5 % in the H1975-DM xenograft tumor model. Compound 8h was confirmed to be safe with no significant side effects as showed by the results of in vitro assay of human normal cells and the sections of animals major organs. Mechanism studies showed that in addition to inhibiting EGFR mutations, 8h can also target the tumor microenvironment and induce tumor cell apoptosis. All these results indicate that 8h deserves further investigation as an EGFR inhibitor to overcome C797S-mediated resistance.