Hemiphragma heterophyllum Wall.is a sole species belonging to the genus Hemiphragma (Scrophulariaceae),used as folk medicine of Yi people for the treatment of pharyngitis,periodontitis,rheumatism,abnormal menstruation,and traumatic injury.Phytochemical investigation on the chemical constituents from the extract of the whole plant ofH.heterophyllum led to the isolation of two sesquineolignans,(-)-sibiricumin B (1),a new spirodienone structure,and (-)-sibiricumin A (2),the known analogue that obtained from this plant for the first time.The structures were elucidated by extensive NMR experiments,high-resolution electron ionization mass spectrum,chiroptical properties,and electronic circular dichroism (ECD) spectra.To the best of our knowledge,only four sesquineolignans (woorenol,1 pinobatol,2 and (+)/(-)-sibiricumin A3) with a spiro skeleton has been reported thus far.Moreover,compounds 1 and 2 were evaluated for their anti-inflammatory,and all of them showed week ability to inhibit NO production of LPS-stimulated RAW264.7 macrophages.