(Rac)-Arnebin 1 ((Rac)-β,β-Dimethylacrylalkannin) is the racemate of β,β-Dimethylacrylalkannin and/or β,β-Dimethylacrylshikonin. β,β-Dimethylacrylalkannin and β,β-Dimethylacrylshikonin are napthoquinones isolated from Arnebia nobilis. β,β-Dimethylacrylshikonin has anti-tumor activity.
