Synthesis and biological evaluation of certain hydrazonoindolin-2-one derivatives as new potent anti-proliferative...

In connection with our research program on the development of novel indolin-2-one-based anticancer candidates, herein we report the design and synthesis of different series of hydrazonoindolin-2-ones 3a-e, 5a-e, 7a-c, and 10a-l. The synthesised derivatives were in vitro evaluated for their anti-proliferative activity towards lung A-549, colon HT-29, and breast ZR-75 human cancer cell lines. Compounds 5b, 5c, 7b, and 10e emerged as the most potent derivatives with average IC₅₀ values of 4.37, 2.53, 2.14, and 4.66 µM, respectively, which are superior to Sunitinib (average IC₅₀ = 8.11 µM). Furthermore, compounds 7b and 10e were evaluated for their effects on cell cycle progression and levels of phosphorylated retinoblastoma (Rb) protein in the A-549 cancer cell line. Moreover, 7b and 10e inhibited the cell growth of the multidrug-resistant lung cancer NCI-H69AR cell line with IC₅₀ = 16 µM. In addition, the cytotoxic activities of 7b and 10e were assessed towards three non-tumorigenic cell lines (Intestine IEC-6, Breast MCF-10A, and Fibroblast Swiss-3t3) where both compounds displayed mean tumor selectivity index (1.6 and 1.8) higher than that of Sunitinib (1.4).