A concise route for the total syntheses of benzopranylchalcones from 2,4,6-trihydroxyacetophone(3) and citral(8), by means of cyclization, methoxy-protection and aldol-condensation is described. Two benzopranylchalcones, Boesenbergin B(1) and Boesenbergin A(2) were synthesized from 2,4,6-(trihydroxyacetophone)(3), citral(8) and benzaldehyde(9) via the route. The total yields of compounds 1 and 2 were 26% and 11%, respectively. In the cyclization step, the yields of key intermediates 4 and 7 were 40% and 42%, respectively.
