Cytotoxic tremulanes and 5,6-secotremulanes, four new sesquiterpenoids from a plant-associated fungus X1-2

Abstract

Two new tremulanes and two new 5,6-secotremulanes, davotremulanes A-D 1–4, along with four known compounds 5–8, were isolated from the culture extract of X1-2, an unidentified plant-associated fungus, which was isolated from the endangered plant, Davidia involucrate Baill. in Shennongjia District. The structures of new compounds 1–4 were established on the basis of extensive spectroscopic analysis. Compounds 1–8 were evaluated for cytotoxic activity to four cancer cell lines, and compounds 1, 2 and 5 displayed selectively moderate activities to A549 cell line with IC₅₀ at 15.3, 25.2, 35.2 μg/mL.

Keywords:

• Tremulanes
• 5,6-secotremulanes
• plant-associated fungus
• secondary metabolites
• cytotoxic activity

Disclosure statement

No potential conflict of interest was reported by the authors.

Funding

This work was financially supported by the Natural Science Foundation of China [grant number 21002058], [grant number 21272137]; Science Foundation of China Three Gorges Universtiy [grant number KJ2011B003].