An efficient and concise synthesis of biologically interesting pyranochromenes by ethylenediamine diacetate-catalyzed double condensation of substituted trihydroxybenzenes to α,β-unsaturated aldehydes and application to natural product analoges

Abstract

A new methodology for the preparation of pyranochromenes was developed starting from substituted trihydroxybenzenes. This methodology was applied successfully to the total synthesis of biologically interesting compounds, clusiaphenone A, octandrenolone, O-methyloctandrenolone, trans-3‴, 4‴-dihydro-3‴,4‴-dihydroxy-O-methyloctandrenolone, trans-3″,4″-dihydro-3″,4″-dihydroxy-O- methyloctandrenolone, flemiculosin, laxichalcone, and racemic 3-deoxy-Ms-II.