Diving into the world of marine 2,11-cyclized cembranoids: a summary of new compounds and their biological activities

Abstract

Covering: 2010 to 2020

The class of 2,11-cyclized cembranoids is particularly widespread in marine Octocorallia, especially Alcyonacea and Gorgonacea, and has been extensively studied. Following a previous review published in 2010, the accumulated knowledge from the past decade will be presented here. All 2,11-cyclized cembranoids share a bicyclo[8.4.0]tetradecane core that is in most of the known compounds oxidatively modified to result in the 15-oxatricyclo[6.6.1.0^2,7]pentadecane system. Multiple further oxidation and acylation patterns can be observed, while halogenated compounds are surprisingly rare. One new sulfur-containing and a few seco-compounds have also been reported. The biosynthetic pathways to this fascinating class of natural products have not been studied to date, but a plausible biosynthetic hypothesis is presented that allows for a structured discussion of the compounds according to their carbon skeletons and oxidation patterns. Biological activities towards 2,11-cyclized diterpenes are also included.