| Summary: | New terpendoles N-P (<b>1–3</b>) were isolated along with 8 structurally related known compounds including terpendoles and voluhemins from a culture broth of the fungus <i>Volutella citrinella</i> BF-0440. The structures of <b>1–3</b> were elucidated using various spectroscopic experiments including 1D- and 2D-NMR. All compounds <b>1–3</b> contained a common indole–diterpene backbone. Compounds <b>2</b> and <b>3</b> had 7 and 6 consecutive ring systems with an indole ring, respectively, whereas <b>1</b> had a unique indolinone plus 4 consecutive ring system. Compounds <b>2</b> and <b>3</b> inhibited both sterol <i>O</i>-acyltransferase 1 and 2 isozymes, but <b>1</b> lost the inhibitory activity. Structure–activity relationships of fungal indole–diterpene compounds are discussed.
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