Total Synthesis of Naphterpin and Marinone Natural Products.

A concise and divergent strategy for the synthesis of the naphterpin and marinone meroterpenoid families has been developed. The approach features a succession of pericyclic reactions-an aromatic Claisen rearrangement, a retro-6π-electrocyclization, and two Diels-Alder reactions-which facilitated the first total synthesis of naphterpin itself in five steps from 2,5-dimethoxyphenol, alongside similar syntheses of 7-demethylnaphterpin and debromomarinone. Late-stage oxidation and bromination reactions were also investigated, leading to the first total syntheses of naphterpins B and C and isomarinone.