The novel total synthesis of icaritin (1), naturally occurring with important bioactive 8-prenylflavonoid, was
performed via a reaction sequence of 8 steps including Baker-Venkataraman reaction, chemoselective benzyl or
methoxymethyl protection, dimethyldioxirane (DMDO) oxidation, O-prenylation, Claisen rearrangement and deprotection,
starting from 2,4,6-trihydroxyacetophenone and 4-hydroxybenzoic acid in overall yields of 23%. The key step was
Claisen rearrangement under microwave irradiation. MS, 1H and 13C NMR techniques have been used to confirm the
structures of all synthetic compounds.