Antitumor photosensitizer-4 (compound 10b) is a potent tyrosine kinase inhibitor (TKI) targeting ABCG2. Antitumor photosensitizer-4 is a photosensitizer (PS) consisting of a conjugate of dasatinib and imatinib. Antitumor photosensitizer-4 induces apoptosis and ROS production and exhibits strong phototoxicity to HepG2 and B16-F10 cells.