Regioselective synthesis of natural 6-prenylpolyhydroxyisoflavone (lupisoflavone) and lupisoflavone hydrate with hypervalent iodine reagents

摘要

The Pd(0)-catalyzed coupling reaction of 6-iodotetraalkoxyisoflavone, which was obtained from the oxidative rearrangement of 3'-iodotetraalkoxychalcones, with 2-methyl-3-butyn-2-ol in heating condition affords 6-alkynylisoflavone. Hydrogenation of 6-iodotetraalkoxyisoflavone followed by acid-catalyzed dehydration with p-TsOH·H _2O gave lupisoflavone.