EGFR/HER2/TS-IN-2 (compound 17) is a potent EGFR/HER2 and TS ( Thymidylate synthase ) inhibitor, with IC 50 values of 0.173, 0.125, and 1.12 μM, respectively. EGFR/HER2/TS-IN-2 shows cytotoxic activity against MDA-MB-231 cancer cell lines, with an IC 50 of 1.69 µM.