The biosynthesis of phenols. Part XIX. Synthesis of the polyhydroxybenzophenone derivative, sulochrin, of the gris-2′,5′-diene-3,4′-dione, trypacidin, and of related compounds

Abstract

The photo-Fries rearrangement of depsides, and trifluoroacetic anhydride-catalysed acylations of orcinol, and its derivatives, have been used for the synthesis of sulochrin (I) and related benzophenones which were hydroxylated in two or more of the 2,2′,6,6′- positions. Trypacidin (IV) and a related gris-2′,5′-diene-3,4′-dione have been synthesised by the action of one-electron oxidising agents on the appropriate polyhydroxybenzophenones.