Silver-catalyzed one-pot synthesis of arylnaphthalene lactone natural products.

Naturally occurring arylnaphthalene lactone lignans have demonstrated a variety of valuable medicinal chemistry properties and have therefore been of continued interest to drug discovery research. Our group has demonstrated a silver-catalyzed one-pot synthesis of the arylnaphthalene lactone core using carbon dioxide, phenylpropargyl chloride, and phenylacetylene. This new approach has been employed in the synthesis of six arylnaphthalene lactone natural products: retrochinensin (1), justicidin B (2), retrojusticidin B (3), chinensin (4), justicidin E (5), and taiwanin C (6). Additionally, an arylnaphthalene lactone regioisomer was isolated (9), which we refer to as isoretrojusticidin B.