A new series of pyridine and pyrimidine derivatives is designed and synthesized as potential antitumor molecules. The tested compounds show promising in vitro cytotoxic activity against HL-60 cell line as eight compounds: 4, 6, 11, 13, 14, 15, 18 and 21 exhibit potent cytotoxic activity in sub-micromolar concentration higher than the combretastatin A4 (CA-4). Compound 21 shows a cytotoxic activity 5-fold more potent than CA-4 on HL-60 cells. DNA-Flow cytometry cell cycle analysis and annexin-V assay on HL-60 cells show that compounds 4, 18 and 21 exhibit potent cell growth inhibition, cell cycle arrest at G/M phase and pro-apoptotic inducing activities. The percentage inhibition assay of β-tubulin polymerization on HL-60 cells shows that the antitumor activity of the tested compounds appears to correlate well with its ability to inhibit β-tubulin polymerization. In addition, enzyme-linked immunosorbene assay (ELlSA) measurement for compound 21 shows apoptotic inducing activities through significant up regulation of p53, Bax/Bcl-2 ratio and caspase-3 proteins parallel to down regulation of the level of survivin proteins.

In this work, design, synthesis, and screening of thiophene carboxamides 4-13 and 16-23 as dual vascular endothelial growth factor receptors (VEGFRs) and mitotic inhibitors was reported. All compounds were screened against two gastrointestinal solid cancer cells, HepG-2 and HCT-116 cell lines. The most active cytotoxic derivatives 5 and 21 displayed 2.3- and 1.7-fold higher cytotoxicity than Sorafenib against HepG-2 cells. Cell cycle and apoptosis analyses for compounds 5 and 21 showed cells accumulation in the sub-G1 phase, and cell cycle arrest at G2/M phase. The apoptotic inducing activities of compounds 5 and 21were correlated to the elevation of p53, increase in Bax/Bcl-2 ratio, and increase in caspase-3/7.Compounds 5 and 21 showed potent inhibition againstVEGFR-2 (IC = 0.59 and 1.29 μM) and β-tubulin polymerization (73% and 86% inhibition at their IC values).Molecular docking was performed with VEGFR-2 and tubulin binding sites to explain the displayed inhibitory activities.

In this work, design, synthesis, and screening of thiophene carboxamides 4-13 and 16-23 as dual vascular endothelial growth factor receptors (VEGFRs) and mitotic inhibitors was reported. All compounds were screened against two gastrointestinal solid cancer cells, HepG-2 and HCT-116 cell lines. The most active cytotoxic derivatives 5 and 21 displayed 2.3- and 1.7-fold higher cytotoxicity than Sorafenib against HepG-2 cells. Cell cycle and apoptosis analyses for compounds 5 and 21 showed cells accumulation in the sub-G1 phase, and cell cycle arrest at G2/M phase. The apoptotic inducing activities of compounds 5 and 21were correlated to the elevation of p53, increase in Bax/Bcl-2 ratio, and increase in caspase-3/7.Compounds 5 and 21 showed potent inhibition againstVEGFR-2 (IC = 0.59 and 1.29 μM) and β-tubulin polymerization (73% and 86% inhibition at their IC values).Molecular docking was performed with VEGFR-2 and tubulin binding sites to explain the displayed inhibitory activities.

A series of novel tetrahydrobenzothieno[2,3-d]pyrimidine urea derivatives was synthesized according to fragment-based design strategy. They were evaluated for their anticancer activity against MCF-7 cell line. Three compounds 9c, 9d and 11b showed 1.5-1.03 folds more potent anticancer activity than doxorubicin. In this study, a promising multi-sited enzyme small molecule inhibitor 9c, which showed the most potent anti-proliferative activity, was identified. The anti-proliferative activity of this compound appears to correlate well with its ability to inhibit topoisomerase II (IC = 9.29 μM). Moreover, compound 9c showed excellent VEGFR-2 inhibitory activity, at the sub-micromolar level with ICvalue 0.2 μM, which is 2.1 folds more potent than sorafenib. Moreover, activation of damage response pathway of the DNA leads to cell cycle arrest at G2/M phase, accumulation of cells in pre-G1 phase and annexin-V and propidium iodide staining, indicating that cell death proceeds through an apoptotic mechanism. Compound 9c showed potent pro-apoptotic effect through induction of the intrinsic mitochondrial pathway of apoptosis. This mechanistic pathway was confirmed by a significant increase in the expression of the tumor suppressor gene p53, elevation in Bax/BCL-2 ratio and a significant increase in the level of active caspase-3. Quantitative structure-activity relationship (QSAR) studies delivered equations of five 3D descriptors with R = 0.814. This QSAR model provides an effective technique for understanding the observed antitumor properties and thus could be adopted for developing effective lead structures.