Chemoprevention is one of the important areas of cancer prevention research. Among all the approaches, activate the phase ?? metabolic enzymes biotransformation activity against the carcinogens results blocking or inhibiting cancer development process is most active investigation area. Nrf2 protein is the key transcription factor for induction the phase ?? metabolic genes expression, therefore, to develop different Nrf2-activators will provide a new strategies for anti-cancer treatment. Most of coumarin derivatives show various biological activity, such as antibiotic (novobiocin), anticoagulant(dicoumarol, warfarin), and rodenticides(warfarin). Recently studies also shown that the functional groups, the ??, ??-unsaturated ketone, might activate the Nrf2-signaling pathway, therefore, various coumarin-derivatives were synthesized and tested Nrf2-activation ability in our laboratory.