A new terpestacin-type sesterterpenoid with tricyclic 3/15/5 scaffold from an endophytic fungus Neofusicoccum sp. J019

Chemical investigation of an endophytic fungus, Neofusicoccum sp. J019, isolated from the plant species Cynanchum chinense R. Br., has led to the identification of an undescribed terpestacin-type sesterterpenoid, neofusistacin (1), together with two analogues (2 and 3). The structure of 1 was elucidated by extensive spectroscopic analyses including UV, IR, 1D, and 2D NMR, HRESIMS, and its absolute configuration was unambiguously confirmed by a single crystal X-ray diffraction analysis. Compound 1 is featured by a rare 3/15/5-fused tricyclic scaffold in terpestacin-type sesterterpenoid. The anti-inflammatory activities of compounds 1–3 were evaluated in vitro, but none of them showed obvious anti-inflammatory activities at the concentration of 100 μM. No antibacterial activity against Escherichia coli ATCC 25922, Salmonella enterica subsp. enterica ATCC 14028, and Staphylococcus aureus subsp. aureus ATCC 29213 was found for compounds 1–3 at the concentration of 100 μM.