Antiviral mono- and bis-prenylated C6–C3 derivatives from the roots of Illicium oligandrum

Abstract Four new bis-prenylated C 6 –C 3 derivatives, illioliganpyranones B–C ( 1 and 4 ) and illioliganfuranones E–F ( 3 and 5 ), and six new mono-prenylated C 6 –C 3 compounds, illioliganfuranone G ( 2 ), illioliganfuranol A ( 6 ), illioliganpyranone D ( 7 ), illioliganones J–K ( 8 and 9 ), and illioliganpyranol A ( 10 ), were isolated from the CHCl 3 extract of Illicium oligandrum roots. The structures of 1 – 10 were determined through interpretation of their spectroscopic data, including 1D and 2D NMR, HRESIMS, and CD experimental results, and the modified Mosher's method. The structure of illioliganpyranone B ( 1 ) was confirmed by single-crystal X-ray diffraction analysis. Compounds 1 and 3 – 5 are the first examples of linear bis-prenylated C 6 –C 3 derivatives featuring ether bond connectivity. The in vitro activity of these compounds was evaluated against Coxsackievirus B3 (CVB3) and influenza virus A/Hanfang/359/95 (H3N2). Compounds 1 , 3 – 5 and 6 demonstrated potent antiviral activity against CVB3, with IC 50 values ranging from 3.70 to 11.11 μM and SI values ranging from 5.2 to 21.1, whereas compounds 6 and 7 were found to exhibit potent activity against influenza virus A H3N2 with IC 50 values of 5.55 and 2.24 μM and SI values of 18.0 and 8.6, respectively.