The bioactivity-guided isolation of potentially active natural products has been widely utilized in pharmaceutical discovery.In this study,by screening fungal extracts against coxsackievirus B3(CVB3),three new aspocha...The bioactivity-guided isolation of potentially active natural products has been widely utilized in pharmaceutical discovery.In this study,by screening fungal extracts against coxsackievirus B3(CVB3),three new aspochalasins,templichalasins A-C(1-3),along with six known aspochalasins(4-9)were isolated from an active extract derived from the endophytic fungus Aspergillus templicola LHWf045.Compound 1 features a unique 5/6/5/7/5 pentacyclic ring system,while compounds 2 and 3 possess unusual 5/6/6/7 tetracyclic skeletons.Their structures were characterized through extensive spectroscopic analyses,electronic circular dichroism(ECD)calculations,and single-crystal X-ray diffraction analysis.Additionally,we demonstrated that compound 4 can be readily converted into compounds 1-3 under mild acidic conditions and proposed a plausible mechanism for this conversion.Bioactivity evaluation of compounds 1-9 against CVB3 revealed the inhibitory effects of all compounds against the virus.Notably,compound 9 exhibited superior antiviral activity,surpassing the commercial drug ribavirin in selectivity index(SI)value.展开更多
基金supported by the National Natural Science Foundation of China(Nos.31972852,32371496,and 81903527)the Key Project at Central Government Level:the Ability Establishment of Sustainable Use for Valuable Chinese Medicine Resources(No.2060302)。
文摘The bioactivity-guided isolation of potentially active natural products has been widely utilized in pharmaceutical discovery.In this study,by screening fungal extracts against coxsackievirus B3(CVB3),three new aspochalasins,templichalasins A-C(1-3),along with six known aspochalasins(4-9)were isolated from an active extract derived from the endophytic fungus Aspergillus templicola LHWf045.Compound 1 features a unique 5/6/5/7/5 pentacyclic ring system,while compounds 2 and 3 possess unusual 5/6/6/7 tetracyclic skeletons.Their structures were characterized through extensive spectroscopic analyses,electronic circular dichroism(ECD)calculations,and single-crystal X-ray diffraction analysis.Additionally,we demonstrated that compound 4 can be readily converted into compounds 1-3 under mild acidic conditions and proposed a plausible mechanism for this conversion.Bioactivity evaluation of compounds 1-9 against CVB3 revealed the inhibitory effects of all compounds against the virus.Notably,compound 9 exhibited superior antiviral activity,surpassing the commercial drug ribavirin in selectivity index(SI)value.
