Synthesis and biological evaluation of quinoxaline derivatives as tubulin polymerization inhibitors that elevate intracellular ROS and triggers apoptosis via mitochondrial pathway.

A series of novel quinoxaline derivatives were synthesized and evaluated for their antiproliferative activity in three human cancer cell lines. Compound 12 exhibited the most potent antiproliferative activity with IC in the range of 0.19-0.51 μM. The compound inhibited tubulin polymerization and disrupted the microtubule network, leading to G2/M phase arrest. Furthermore, compound 12 induced ROS production and malfunction of mitochondrial membrane potential. Compound 12 led to cancer cells apoptosis in a dose-dependent manner. Western blot analysis showed that compound 12 induced up-regulation of p21 and affected the expression of cell cycle-related proteins. The binding mode was also probed by molecular docking.