Synthesis of 8-aryl-substituted coumarins based on ring-closing metathesis and Suzuki-Miyaura coupling: synthesis of a furyl coumarin natural product from Galipea panamensis.

The synthesis of 7-methoxy-8-(4-methyl-3-furyl)-2H-chromen-2-one, a natural product with antileishmanial activity recently isolated from the plant Galipea panamensis, is described. The key step is a Suzuki-Miyaura coupling of a furan-3-boronic acid and an 8-halocoumarin, which is advantageously synthesized using a ring-closing metathesis reaction. Several non-natural analogues are also available along these lines.