PROBLEM TO BE SOLVED: To provide a prophylactic or therapeutic agent for a disease having an Nrf2 activating effect and associated with oxidative stress such as hepatitis, cardiovascular disease, lung disease, renal disease, central nervous system disease, mitochondrial disease, autoimmune disease and the like. .. A compound represented by formula (I) or a salt thereof. [A is a substituted/unsubstituted benzene ring； B is a benzene ring or a pyridine ring； R 1 is a substituted/unsubstituted alkyl group； R 2 and R 3 are each independently H or a substituted/unsubstituted alkyl group； R 4 is a substituted/unsubstituted cyclic group or a substituted/unsubstituted alkyl group； X is —CO— or —SO 2 —； Y is a specific bond, —O— or —N(Ry)—； Ry is H or a substituent； n is 1 or 2] [Selection diagram] None【課題】Nrf2活性化作用を有し、肝炎、心血管性疾患、肺疾患、腎疾患、中枢神経系疾患、ミトコンドリア病、自己免疫疾患等の酸化ストレスが関与する疾患の予防または治療剤の提供。【解決手段】式（Ｉ）で表される化合物またはその塩。[Ａは置換／非置換のベンゼン環；Ｂはベンゼン環又はピリジン環；Ｒ１は置換／非置換のアルキル基；Ｒ２及びＲ３は夫々独立にＨ又は置換／非置換のアルキル基；Ｒ４は置換／非置換の環状基又は置換／非置換のアルキル基；Ｘは、－ＣＯ－又は－ＳＯ２－；Ｙは特定の結合手、－Ｏ－又は－Ｎ（Ｒｙ）－；ＲｙはＨ又は置換基；ｎは１又は２]【選択図】なし
