Sesquiterpenoids from Trichoderma atroviride, an endophytic fungus in Cephalotaxus fortunei

Two new sesquiterpenoids, identified as (rel 1S, 3R, 4R, 7R)-3-5-hydroxy-4-methylpent-3-enyl]-1, 3, 7-trimethyl-2-oxabicyclo 2, 2, 1] heptane (1) and (rel 1S, 3R, 4R, 7R)-3-3, 4-dihydroxy-4-methylpentyl]-1, 3, 7-trimethyl-2-oxabicyclo 2, 2, 1] heptane (2), were isolated from cultures of Trichoderma atroviride (strain no. S361), an endophytic fungal strain residing in the bark of Cephalotaxus fortunei. The structures of compounds 1 and 2 were elucidated by detailed spectroscopic analyses on the basis of NMR, IR, and MS data. Both compounds 1 and 2 were potent inhibitors on NO production in LPS-stimulated RAW264.7 cells, with IC₅₀ values of 15.3 and 9.1 μM, respectively.