Metabolites from the purple heartwood of Mimosoideae. Part 2. Acacia carnei maiden: isolation, synthesis, and reactions of crombeone

Abstract

The range of natural peltogynoid-type chalcone, flavonol, and dihydroflavonol analogues is extended by the recognition of carnein, β-photomethylquercitin, and (+)-2,3-trans-crombeone in the purple heartwood of Acacia carnei.

The first synthesis of a 2,3-trans-peltogynone, crombeone tetramethyl ether, is effected and its catalytic reduction leads to a 2,3-trans-3,4-cis-peltogynol analogue. Crombeone itself is subject to a variety of methylene insertion reactions with diazomethane.