Sesquiterpenes from Rhizomes of Cyperus rotundus with Cytotoxic Activities on Human Cancer Cells in vitro

Two new sesquiterpenes, cyperusol A 3 ( 1 ) and 3 β ‐hydroxycyperenoic acid ( 2 ), along with three known sesquiterpenes, britanlin E ( 3 ), 1 β ,4 α ‐dihydroxyeudesm‐11‐ene ( 4 ), and 11,12‐dihydroxyeudesm‐4‐en‐3‐one ( 5 ), were isolated from the AcOEt‐soluble fraction of rhizomes of Cyperus rotundus L. The structures of 1 and 2 were elucidated by physical and spectroscopic methods ( 1 H‐ and 13 C‐NMR, 2D‐NMR, and MS). All of the isolates, 1 – 5 , were evaluated for their cytotoxic activities against human ovarian cancer cells (A2780) and endometrial adenocarcinoma cells ( Ishikawa ) using MTT assays.