FM19G11 is a hypoxia-inducible factor-1-alpha (HIF-1α) inhibitor, and it inhibits hypoxia-induced luciferase activity with an IC50 of 80 nM in HeLa cells. FM19G11 modulates other signaling pathways, including mTOR and PI3K/Akt/eNOS, when the HIF-1α pathway is inactivated under normoxic conditions.