Hypoxia is one of the inevitable circumstances in various tumors and results in tumor resistance to radiotherapy and chemotherapy. The present data showed that 3-(4- bromophenyl)-2-(ethylsulfonyl)-6-methylquinoxaline 1, 4-dioxide (Q39), derived from Quinoxaline 1, 4-Di-N-oxide, possessed high anti-cancer activity in hypoxia. Cytotoxicity assay demonstrated that Q39 is a potential and high efficient anti-cancer compound in all ...