Purity >98%. MCI-186 is a free radical scavenger with diverse protective effects in vivo . Most notably, it reduces damage due to ischemia-reperfusion injury in lung, liver, and brain in animal models of transplant, infection, traumatic brain injury, and stroke. MCI-186 provides these protective effects, at least in part, by reducing reactive oxygen species, inhibiting apoptosis, and blocking nonenzymatic peroxidation and lipoxygenase activity.