Investigation of the entomogenous fungus Setosphaeria rostrate LGWB-10 from Harmonia axyridis led to the isolation of four new isocoumarin derivatives,setosphlides A-D(1-4),and four known analogues(5-8).Their planar s...Investigation of the entomogenous fungus Setosphaeria rostrate LGWB-10 from Harmonia axyridis led to the isolation of four new isocoumarin derivatives,setosphlides A-D(1-4),and four known analogues(5-8).Their planar structures and the relative configurations were elucidated by comprehensive spectroscopic methods.The absolute configurations of isocoumarin nucleus for 1-4 were elucidated by their ECD spectra.The C-10 relative configurations for the pair of C-10 epimers(1 and 2)were established by comparing the magnitude of the computed 13C NMR chemical shifts(Δδcalcd.)with the experimental 13C NMR values(Δδexp.)for the epimers.All of the isolated compounds(1-8)were evaluated for their cytotoxicities against four human tumor cell lines MCF-7,MGC-803,HeLa,and Huh-7.展开更多
基金This work was funded by the National Natural Science Foundation of China(31672070)National Key Research and Development Program of China(2017YFD0201400 and 2017YFD0201401)the High Performance Computer Center of Hebei University.
文摘Investigation of the entomogenous fungus Setosphaeria rostrate LGWB-10 from Harmonia axyridis led to the isolation of four new isocoumarin derivatives,setosphlides A-D(1-4),and four known analogues(5-8).Their planar structures and the relative configurations were elucidated by comprehensive spectroscopic methods.The absolute configurations of isocoumarin nucleus for 1-4 were elucidated by their ECD spectra.The C-10 relative configurations for the pair of C-10 epimers(1 and 2)were established by comparing the magnitude of the computed 13C NMR chemical shifts(Δδcalcd.)with the experimental 13C NMR values(Δδexp.)for the epimers.All of the isolated compounds(1-8)were evaluated for their cytotoxicities against four human tumor cell lines MCF-7,MGC-803,HeLa,and Huh-7.