TP53 and cancer: Several of the synthesized compounds (R1 = 5-Cl/5-Br, R2 = 3-Cl/3-Cl, R3 = H/3-Cl, R4 = H/2-Cl) demonstrated promising antiproliferative activity (MTT method) against MCF7, MDA-MB-231 (breast), HCT116 (p53+/+), HCT116 (p53−/−) (colon) cancer, and HEK 293T (embryonic kidney non-cancer) cell lines (IC50 = 9.8 ± 1.5/9.5 ± 3.1, 8.9 ± 1.9/7.6 ± 2.4, 16.3 ± 0.2/13.9 ± 1.1, 17.9 ± 0.6/17.7 ± 1.3, >100/21.4 ± 7.4 μM, respectively) and compared with that of nutlin-3a [IC50 = 4.0 ± 1.2, 47.8 ± 1.9 μM against HCT116 (p53+/+), and HCT116 (p53−/−), respectively] (Supplementary Figure S20).