An object of the present invention is to provide a pharmaceutical agent useful for treating and preventing neurological disease, having satisfactory solubility and oxidative stress-mediated cell death suppressive activity as well as capable of exhibiting excellent blood-brain barrier permeability. The present invention is directed to an acylaminoimidazole derivative represented by general formula (I) or a salt thereof, and a pharmaceutical and a therapeutic or preventive agent for neurological disease containing the same, as an active ingredient.本發明之課題在於提供一種具有良好之溶解性及氧化壓力性之細胞死亡抑制活性，並且亦可發揮優異之血腦障壁通透性之用於治療及預防神經疾病之藥劑。本發明係一種通式(I)所示之醯胺基咪唑衍生物或其鹽，以及以此作為有效成分之醫藥及神經疾病之治療劑或預防劑。
