Biomimetic synthesis of zeylanone and zeylanone epoxide by dimerization of 2-methyl-1,4-naphthoquinone.

A biomimetic synthesis of zeylanone and zeylanone epoxide, which are natural dimeric naphthoquinones, has been accomplished starting from plumbagin, a natural monomeric naphthoquinone. The key features of our synthesis are cascade intermolecular and intramolecular Michael reactions, followed by epoxidation of the resultant hydroquinone with molecular oxygen.