Background Most recent synthetic efforts toward khellin have been directed at its benzofuran precursor khellinone (9P since it can be converted to khellin in 85% yield by a Claisen-like condensation with ethyl acetate, followed by acid-catalyzed cyclization and dehydration. & Khellinone has the further advantage that it can be converted to khellin analogues when substituted acetates are used in the condensationa2 Historically, construction of the fully ...