PROBLEM TO BE SOLVED: To provide an anticancer agent, particularly an anticancer agent against oral cavity cancer, and foods, medical products and quasi drugs including them.SOLUTION: There are provided a new quercetin derivative shown by formula (1) or pharmaceutically allowable salts thereof, and an anticancer agent including the new quercetin derivative and the like.COPYRIGHT: (C)2014,JPO&INPIT【課題】抗癌剤、特に口腔癌に対する抗癌剤、これを含有する食品、医薬品、医薬部外品の提供。【解決手段】式(1):で示される新規ケルセチン誘導体又はその薬学的に許容可能な塩、前記新規ケルセチン誘導体等を含有する。【選択図】なし