Optimization of Brigatinib as New Wild-Type Sparing Inhibitors of EGFR(T790M/C797S) Mutants

A series of brigatinib derivatives were designed and synthesized as new potent and selective EGFR(T790M/C797S) inhibitors. One of the most potent and selective compounds 18k strongly suppressed the EGFR(L858R/T790M/C797S) and EGFR (19Del/T790M/C797S) kinases with IC50 values of 0.7 and 3.6 nM, respectively, which were over 54-fold more potent than the lead compound. 18k also demonstrated promising EGFR(T790M/C797S) mutant selectivity, and was 94-fold less potent against the wild type EGFR. A cocrystal structure of EGFR(T790M/C797S) with a close derivative 18f was solved to provide insight on the inhibitor's binding mode. Moreover, compound 18k was orally bioavailable and demonstrated highly desirable PK properties, making it a promising lead compound for further structural optimization.