Two New Sesquiterpenoids Isolated From Cyperus rotundus L

Two new sesquiterpenoids, isocyperotundone (1) and 1,4-epoxy-4-hydroxy-4,5-seco-guain-11-en-5-one (2), together with 6 known sesquiterpenoids, cyperotundone (3), cyperenoic acid (4), sugetriol triacetate (5), cyperusol A3 (6), cyperusol A2 (7), and cyperusol A1 (8), were isolated from the methanol extract of the rhizomes of Cyperus rotundus L. High-resolution electrospray ionization mass spectrometry and 1-dimensional (1D) and 2D nuclear magnetic resonance spectroscopy were used to establish the structures of all the compounds. All the compounds were tested for activity on nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling. Compounds 1-7 exhibited inhibitory activity on tumor necrosis factor-α-induced activation of the NF-κB pathway, with half-maximal inhibitory concentration values ranging from 34.5 to 73.7 μmol/L.