摘要
Objective: To study secondary metabolites from endophytic fungus Colletotruchum sp. HK-08 originated from the leaves of Nerium indicum.Methods: The compounds were isolated by various column chromatographic techniques, and their structures were elucidated by spectroscopic techniques [high resolution electrospray ionization mass spectroscopy(HRESIMS), one-dimensional(1D) and two-dimensional(2D) nuclear magnetic resonance spectroscopy(NMR)], as well as comparison with literature data. The Ellman method was used to determine the acetylcholinesterase(ACh E) inhibitory activity.Results: Four indole derivatives were identified from Colletotruchum sp. HK-08, including 6’-hydroxymonaspiloindole(1), 2-(2-oxoindolin-3-yl)ethyl 2-(4-hydroxyphenyl) acetate(2), 2-(2-oxoindolin-3-yl)ethyl 2-(2-hydroxyphenyl)acetate(3), and monaspiloindole(4). Compound 4 presented weak ACh E inhibitory activity with IC50value of(69.30 ± 6.27) μmol/L [tacrine as the positive control, with IC50value of(0.61 ± 0.07) μmol/L].Conclusion: Compounds 1–3 were new compounds, and compound 4 had weak ACh E inhibitory activity.
基金
supported by the Hainan Natural Science Foundation(No.220RC702).