Scientists from the Korea Research Institute of Chemical Technology and Yonsei University have identified N4-(indolin-7-yl)-N2-(2-alkoxypyridin-3-yl)pyrimidine-2,4-diamine derivatives acting as EGFR (HER1; erbB1) and/or HER2 (erbB2) mutant inhibitors and therefore reported to be useful for the treatment of cancer.