Phenol oxidation and biosynthesis. Part XX. The mechanism of erysodienone formation in vitro

Abstract

The formation of erysodienone from bis-(3-hydroxy-4-methoxyphenethyl) amine in vitro has been shown to occur via an initial coupling to a 9-membered ring bridged biphenyl. Further oxidation to the diphenoquinone followed by an intramolecular attack of the nitrogen function leads to the dienone. The alternative intermediate, 5-hydroxy-N-(3-hydroxy-4-methoxyphenethyl)-6-methoxyindoline has been synthesised and shown not to give a dienone on oxidation.