Design, synthesis, apoptotic, and antiproliferative effects of 5-chloro-3- (2-methoxyvinyl)-indole-2-carboxamides and pyrido[3,4-b]indol-1-ones as potent EGFR(WT/)EGFR(T790M) inhibitors

A new series of indole-2-carboxamides 5a-g, 6a-f and pyrido[3,4-b]indol-1-ones 7a and 7b have been developed as new antiproliferative agents that target both wild and mutant type EGFR. The antiproliferative effect of the new compounds was studied. 5c, 5d, 5f, 5 g, 6e, and 6f have the highest antiproliferative activity with GI(50) values ranging from 29 nM to 47 nM in comparison to the reference erlotinib (GI(50) = 33 nM). Compounds 5d, 5f, and 5 g inhibited EGFR(WT) with IC(50) values ranging from 68 to 85 nM while the GI(50) of erlotinib is 80 nM. Moreover, compounds 5f and 5 g had the most potent inhibitory activity against EGFR(T790M) with IC(50) values of 9.5 ± 2 and 11.9 ± 3 nM, respectively, being equivalent to the reference osimertinib (IC(50) = 8 ± 2 nM). Compounds 5f and 5 g demonstrated excellent caspase-3 protein overexpression levels of 560.2 ± 5.0 and 542.5 ± 5.0 pg/mL, respectively, being more active than the reference staurosporine (503.2 ± 4.0 pg/mL). they also increase the level of caspase 8, and Bax while decreasing the levels of anti-apoptotic Bcl2 protein. Computational docking studies supported the enzyme inhibition results and provided favourable dual binding modes for both compounds 5f and 5 g within EGFR(WT) and EGFR(T790M) active sites. Finally, in silico ADME/pharmacokinetic studies predict good safety and pharmacokinetic profile of the most active compounds.