A biomimetic synthetic approach to the frondosins

Abstract

The frondosins are a family of five marine sponge-derived meroterpenoids. We propose that the 6-7 ring system common to each of the frondosins is biosynthesized via ring expansion of a 6–6 ring system. Compelling evidence in favour of this proposal was obtained in the form of a biomimetic synthesis of the frondosin 6–7 ring system, which features a highly stereo- and regio-selective ring expansion cascade reaction as the key step.