Two New Sesquiterpenoids and a New Shikimic Acid Metabolite from Mangrove Sediment-Derived Fungus Roussoella sp. SCSIO 41427.

Two new sesquiterpenoid derivatives, elgonenes M ( 1 ) and N ( 2 ), and a new shikimic acid metabolite, methyl 5- O -acetyl-5- epi -shikimate ( 3 ), were isolated from the mangrove sediment-derived fungus Roussoella sp. SCSIO 41427 together with fourteen known compounds ( 4 - 17 ). The planar structures were elucidated through nuclear magnetic resonance (NMR) and mass spectroscopic (MS) analyses. The relative configurations of 1 - 3 were ascertained by NOESY experiments, while their absolute configurations were determined by electronic circular dichroism (ECD) calculation. Elgonene M ( 1 ) exhibited inhibition of interleukin-1β (IL-1β) mRNA, a pro-inflammatory cytokine, at a concentration of 5 μM, with an inhibitory ratio of 31.14%. On the other hand, elgonene N ( 2 ) demonstrated inhibition at a concentration of 20 μM, with inhibitory ratios of 27.57%.