Isolation of Dineolignans, Saucernetin-7 and -8, with Nitric Oxide Inhibitory Activity and NMR assignment from Saururus chinensis
Two dineolignans (1,2) with nitric oxide inhibitory activities were isolated from Saururus chinensis (Saururaceae) using silica gel column chromatography. Although the structures, saucernetin-7 (1) and -8 (2), have been already reported, NMR assignment of the two compounds was completed aided by 2D-NMR spectroscopy including 1H-1H COSY, 1H-13C COSY, HMBC and NOESY NMR spectra. Compounds 1 and 2 exhibited significant nitride oxide inhibitory activity in LPS-induced RAW 264.7 cells with IC50 values of 11.3μM and 7.1μM, respectively.