A novel compound having an excellent NFºB inhibitory effect is provided. Specifically disclosed is a compound represented by the following formula (1) or a salt thereof: wherein, R 1 represents a hydrogen atom, a lower alkyl group, or the like； R 2 represents a hydrogen atom, a lower alkyl group, a halogen atom, or the like； R 3 represents a hydrogen atom, a lower alkyl group, a hydroxyl group, or a halogen atom； R 4 represents a hydrogen atom or a lower alkyloxy group； R 5 represents a hydrogen atom, a lower alkyloxy group, a halogen atom, a hydroxyl group, or a methylenedioxy group formed together with R 6 or an isopropylidenedioxy group formed together with R 6 ； R 6 represents a hydrogen atom, a lower alkyloxy group, or a methylenedioxy group formed together with R 5 or an isopropylidenedioxy group formed together with R 5 ； R 7 represents a hydrogen atom or a lower alkyl group； and R 8 represents a hydrogen atom, a hydroxyl group, an amino group, a lower alkylcarbonyloxy group, or a halogen atom.
