New terpenoids and triketides from culture of the fungus Botrysphaeria laricina.

Abstract Three new isopimarane-type diterpenoids, botrysphins G-I (1–3), a new muurolane-type sesquiterpenoid, 11,12-dihydroxylentideusether (4), and two new triketides, 4-dechlorobotrysphone C (5) and 4,5-dihydroxy-3-methoxy-6-undecanoyloxy-2-cyclohexen-1-one (6), together with one known diterpenoid, sphaeropsidin A (7), one sesquiterpenoid, lentideusether (8), and one triketide sphaeropsidone (9), were isolated from culture of the fungus Botrysphaeria laricina associated with the moss Rhodobryum umgiganteum. The structures of the new compounds were established on the basis of extensive spectroscopic techniques including HRMS and 1D and 2D NMR data. Compounds 1 and 2 exhibited NO inhibitory activity with IC50 values of 13.9 μM and 41.9 μM, respectively. At the same time, these two compounds showed quinone reductase inducing activity with 2.7-fold of induction for 1 at 12.5 μM and 1.6-fold for 2 at 25.0 μM.