To gain a better insight into the mechanisms underlying the activity of these compounds, the inhibitory effects of compounds 2b, 2f, and 2i were tested and compared with gefitinib (GE), compound Ref 1, and Ref 2 in the downstream signaling pathway of EGFR in MDA-MB-468 cells, as an EGFR-overexpressed basal-like breast cancer cell line. Here, EGFR is linked to breast carcinoma.