Semisynthesis of prunetin, a bioactive O-methylated isoflavone from naringenin, by the sequential deacetylation of chalcone intermediates and oxidative rearrangement

Abstract

Prunetin (4′,5-dihydroxy-7-methoxyisoflavone) was semisynthesized in 8 steps from readily available naringenin in 26% total yield. The key reaction was chemoenzymatic sequential deacetylation to 6′-acetoxy-2′,4″-dihydroxy-4′-methoxychalcone, the in situ-formed precursor for thallium(III) nitrate-mediated oxidative rearrangement.