Hindawi Publishing Corporation e Scientific World Journal Volume 2014, Article ID 274207, 7 pages http://dx.doi.org/10.1155/2014/274207 Research Article Cytotoxic Activities of Flavonoids from Centaurea scoparia Sayed A. Ahmed and Emadeldin M. Kamel Chemistry Department, Faculty of Science, Beni Suef University, Salah Salem Street, P.O. Box 62514, Beni Suef 62514, Egypt Correspondence should be addressed to Sayed A. Ahmed;
[email protected] Received 17 January 2014; Accepted 22 May 2014; Published 11 June 2014 Academic Editor: Diego Savoia Copyright © 2014 S. A. Ahmed and E. M. Kamel. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Phytochemical studies on the ethanolic extract of the aerial parts of Centaurea scoparia ledtotheisolationof two new flavonoids, 3 ,4 -dihydroxy-(3 ,4 -dihydro-3 -hydroxy-4 -acetoxy)-2 ,2 -dimethylpyrano-(5 ,6 :7,8)-flavone-3-O-- D-glucopyranoside (1)and3,3,4 -trihydroxy-(3 ,4 -dihydro-3 ,4 -dihydroxy)-2 ,2 -dimethylpyrano-(5 ,6 :7,8)-flavone (2), along with eight known flavonoids isolated for the first time from this plant, cynaroside (3), Apigetrin (4), centaureidin (5), oroxylin A(6), 5,7-dihydroxy-3 ,4 ,5 -trimethoxyflavone (7), atalantoflavone (8), 5-hydroxy-3 ,4 ,8-trimethoxy-2 ,2 -dimethylpyrano (5 ,6 :6,7)-flavone (9), and 3 ,4 ,5,8-tetramethoxy-2 ,2 -dimethylpyrano (5 ,6 :6,7)-flavone (10). The structures of the isolated compounds were elucidated by means of spectroscopic tools including 1D and 2D NMR, UV,IR, and mass spectroscopy.