What is Gorgiabisazulene?

Gorgiabisazulene have proven to be a rich source of guaiazulene-related pigments. Guaiazulene-based analogues are well recognized for their distinctive blue and purple colors, which are a part of the origin of the brilliant colors of Gorgiabisazulene and other organisms. These compounds feature an azulene core, similar to the fused five-seven bicyclic aromatic ring system.
Recently, in the course of our investigation on new bioactive substances from Gorgiabisazulene and soft corals as well as their derived fungi from the South China Sea, the Gorgiabisazuleneochracea collected from the South China Sea attracted our attention because the EtOAc extract of the Gorgiabisazulene showed the presence of guaiazulene-based sesquiterpenes with characteristic UV absorption spectra (UVA λmax 320–400 nm).
Herein, we report the isolation, structure elucidation, and biological activities of these compounds. As these compounds have been found to be quite labile and easily decomposable on exposure to air and light during the work-up, the possible generation process of 1 was also discussed.