Isolation, structure elucidation, and synthesis of bisgersolanolide, a novel heptacyclic bis-diterpenoid from the gorgonian octocoral Pseudopterogorgia bipinnata.

[formula: see text] A chemical study of the hexane extracts of the Caribbean gorgonian Pseudopterogorgia bipinnata (Verrill) collected in San Andrés Island, Colombia, has led to the isolation of an unprecedented heptacyclic C40 bis-diterpenoid, bisgersolanolide (1). The structure of this novel secondary metabolite, which was established by spectroscopic studies that included 2D NMR correlation methods, IR, UV, and accurate mass measurements, was confirmed by synthesis.