Design and synthesis of novel 2-(4-(2-(dimethylamino)ethyl)-4H-1,2,4-triazol-3-yl)pyridines as potential antitumor agents.

New 2-(4-(2-(dimethylamino)ethyl)-4H-1,2,4-triazol-3-yl)pyridine derivatives were synthesized and evaluated for their in vitro cytotoxicity against five cancer cell lines namely MKN-45, H460, HT-29, A549 and U87MG, as well as the normal cell line WI-38. Nearly all the compounds exhibited superior potency to sorafenib with a better selectivity towards the MKN-45, H460 and HT-29 cell lines. In addition, the enzymatic screening result demonstrated that the optimized compounds possessed potent Raf kinase inhibition as well as favorable enzyme selectivity. The most promising compound, 11f, showed high levels of cytotoxicity against MKN-45, H460 and HT-29 cells with IC50 values of 51, 72 and 130 nM, respectively, which are 45.5, 30.4 and 27.8 folds higher than the corresponding IC50 values for sorafenib against these cell lines. Structure-activity relationships revealed that the dimethylaminoethyl group was crucial for high activity.