Synthesis of Biologically Active Natural Component 4-Hydroxyderricin Through Water-Accelerated [3,3]-Sigmatropic Rearrangement

摘要

Angelica keiskei has been used in traditional medicine, food and beverages, and exhibited various biological activities, such as antitumor, antibacterial, antioxidant, antidiabetic, antiallergic, antimetastatic, antiulcer, hypotensive, lipid regulatory, and cancer chemopreventive effects. The plant has been reported to contain chalcones, flavanones, and coumarines. Two types of polyphenolic chalcones, 4-hydroxyderricin (1) and xanthoangelol (2), are especially rich in the plant, and the 4-hydroxyderricin exhibited the major responsibility for the various biological activities. Sugamoto reported the synthesis of 4-hydroxyderricin via [1,3]-sigmatropic rearrangement of chalcone ether using montmorillonite K10 which showed relatively low rearrangement yield (Scheme 1), and this is the only reported total synthesis of 1 as far as we know. We recently developed the water-accelerated [3,3]-sigmatropic rearrangement reaction for licochalcone A synthesis and showed advantages promising higher yield and preventive effect to abnormal rearrangement which was known disadvantage of [3,3]-sigmatropic rearrangement reactions. We now report herein the effective total synthesis of biologically active natural product 4-hydroxyderricin.