A new resorcylic acid lactone from the endophytic fungus Chaetosphaeronema sp.

Abstract

A new 14-membered resorcylic acid lactone (RAL₁₄), chaetolactone A (1), along with three known ones (2−4), was obtained from the fermentation of the soil-derived fungus Chaetosphaeronema sp. SSJZ001. Their structures were established based on extensive spectroscopic data analyses (UV, IR, HRESIMS, 1D, and 2D NMR),¹³C NMR chemical shifts calculations coupled with the DP4⁺ probability method, theoretical calculations of ECD spectra, as well as X-ray diffraction analysis. All compounds were evaluated for their cytotoxic effects against A549, HO-8910, and MCF-7 cell lines.

Keywords:

• Endophytic fungus
• Chaetosphaeronema sp.
• resorcylic acid lactones

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was financially supported by the Applied Basic Research Project of Qinghai Province (Grant No. 2022-ZJ-739).