890888-12-7

S3QEL-2 is a cell-permeable, selective suppressor of electron leak from mitochondrial respiratory complex III, inhibiting site III_Qo superoxide production (IC₅₀ = 1.7 μM) without altering normal bioenergetics function. It reduces production of H₂O₂ during oxidation of glutamate plus malate to 25% of the control level. S3QEL-2 also protects against ROS-induced cell stress in pancreatic β-cells and decreases HIF-1α induction in response to hypoxia.

S3QEL 2 supresses superoxide production by complex III in the mitochondria without affecting normal electron flux or cellular oxidative phosphorylation.