Involucrasin C, Anti‐Inflammatory 2,3‐Dihydro‐1H‐Indene Derivative from Chinese Dai Ethnic Medicine Shuteria involucrata

Abstract (±)‐Involucrasin C ( 1 ), a pair of new 2,3‐dihydro‐1 H ‐indene enantiomers, along with an enantiomeric analog ( 2 ), were isolated from Shuteria involucrata . Their structures were established by the basis of comprehensive spectroscopic data analysis and X‐ray crystallographic diffraction. Both 1 and 2 significantly inhibited the secretion of pro‐inflammatory cytokines IL‐6, TNF‐ α , and IL‐1 β , suggesting that these two natural 2,3‐dihydro‐1 H ‐indene derivatives may be active components of S. involucrata and may block inflammation in the initial stage.