A novel compound having an excellent NFκB inhibitory effect is provided. Specifically disclosed is a compound represented by the following formula (1) or a salt thereof:wherein, R1 represents a hydrogen atom, a lower alkyl group, or the likeR2 represents a hydrogen atom, a lower alkyl group, a halogen atom, or the likeR3 represents a hydrogen atom, a lower alkyl group, a hydroxyl group, or a halogen atomR4 represents a hydrogen atom or a lower alkyloxy groupR5 represents a hydrogen atom, a lower alkyloxy group, a halogen atom, a hydroxyl group, or a methylenedioxy group formed together with R6 or an isopropylidenedioxy group formed together with R6R6 represents a hydrogen atom, a lower alkyloxy group, or a methylenedioxy group formed together with R5 or an isopropylidenedioxy group formed together with R5R7 represents a hydrogen atom or a lower alkyl group andR8 represents a hydrogen atom, a hydroxyl group, an amino group, a lower alkylcarbonyloxy group, or a halogen atom.
