Three new C-methylated phenylpropanoid glycosides (1, 2), a new 8-4'-oxyneolignan (3), together with two known analogs (4, 5), were isolated from the rhizomes of Imperata cylindrical Beauv. var. major (Nees) C. E. Hubb. Their structures were determined by spectroscopic and chemical methods. Compounds 1, 2, and 5 (10 μM) exhibited pronounced hepatoprotective activity against N-acetyl-p-aminophenol (APAP)-induced HepG2 cell damage in vitro assays. Furthermore, their antioxidant activities against Fe2+-cysteine-induced rat liver microsomal lipid peroxidation and the effects on the secretion of TNF-α in murine peritoneal macrophages (RAW264.7) induced by lipopolysaccharides were evaluated.
Keywords: C-methylated phenylpropanoid; Graminea; Imperata cylindrical; hepatoprotective; lignan glycoside.