A new series of indoline-2-one derivatives was designed and synthesized based on the essential pharmacophoric features of VEGFR-2 inhibitors. Anti-proliferative activities were assessed for all derivatives against breast (MCF-7) and liver (HepG2) cancer cell lines, using sunitinib as a reference agent. The most potent anti-proliferative derivatives were evaluated for their VEGFR-2 inhibition activity. The effects of the most potent inhibitor, 17a, on cell cycle, apoptosis, and expression of apoptotic markers (caspase-3&-9, BAX, and Bcl-2) were studied. Molecular modeling studies, such as docking simulations, physicochemical properties prediction, and pharmacokinetic profiling were performed. The results revealed that derivatives 5b, 10e, 10g, 15a, and 17a exhibited potent anticancer activities with IC₅₀ values from 0.74–4.62 µM against MCF-7 cell line (sunitinib IC₅₀ = 4.77 µM) and from 1.13–8.81 µM against HepG2 cell line (sunitinib IC₅₀ = 2.23 µM). Furthermore, these compounds displayed potent VEGFR-2 inhibitory activities with IC₅₀ values of 0.160, 0.358, 0.087, 0.180, and 0.078 µM, respectively (sunitinib IC₅₀ = 0.139 µM). Cell cycle analysis demonstrated the ability of 17a to induce a cell cycle arrest of the HepG2 cells at the S phase and increase the total apoptosis by 3.5-fold. Moreover, 17a upregulated the expression levels of apoptotic markers caspase-3 and -9 by 6.9-fold and 3.7-fold, respectively. In addition, 17a increased the expression level of BAX by 2.7-fold while decreasing the expression level of Bcl-2 by 1.9-fold. The molecular docking simulations displayed enhanced binding interactions and similar placement as sunitinib inside the active pocket of VEGFR-2. The molecular modeling calculations showed that all the test compounds were in accordance with Lipinski and Veber rules for oral bioavailability and had promising drug-likeness behavior.

Some new Bis-pyrazoline hybrids 8–17 with dual EGFR and BRAF^V600E inhibitors have been developed. The target compounds were synthesized and tested in vitro against four cancer cell lines. Compounds 12, 15, and 17 demonstrated strong antiproliferative activity with GI₅₀ values of 1.05 µM, 1.50 µM, and 1.20 µM, respectively. Hybrids showed dual inhibition of EGFR and BRAF^V600E. Compounds 12, 15, and 17 inhibited EGFR-like erlotinib and exhibited promising anticancer activity. Compound 12 is the most potent inhibitor of cancer cell proliferation and BRAF^V600E. Compounds 12 and 17 induced apoptosis by increasing caspase 3, 8, and Bax levels, and resulted in the downregulation of the antiapoptotic Bcl2. The molecular docking studies verified that compounds 12, 15, and 17 have the potential to be dual EGFR/BRAF^V600E inhibitors. Additionally, in silico ADMET prediction revealed that most synthesized bis-pyrazoline hybrids have low toxicity and adverse effects. DFT studies for the two most active compounds, 12 and 15, were also carried out. The values of the HOMO and LUMO energies, as well as softness and hardness, were computationally investigated using the DFT method. These findings agreed well with those of the in vitro research and molecular docking study.