Sesquiterpene Lactones from Centaurea s pinosa and Their Antibacterial and Cytotoxic Activities

• Published in: Journal of natural products (Washington, D.C.) D.C.), 2005-09, Vol.68 (9), p.1404-1407
• Main Authors: Saroglou, Vasiliki, Karioti, Anastasia, Demetzos, Costas, Dimas, Kostas, Skaltsa, Helen
• Format: Article
• Language: English
• ISSN: 0163-3864; 1520-6025
• DOI: 10.1021/np058042u

Ten sesquiterpene lactones, 8α-O-(3,4-dihydroxy-2-methylenebutanoyloxy)sonchucarpolide (4-epi-malacitanolide) (1), 8α-O-(4-acetoxy-2-hydroxymethylbuten-2-oyloxy)-4-epi-sonchucarpolide (2), malacitanolide (3), its 4‘-acetyl derivative (4), 8α-O-(3,4-dihydroxy-2-methylenebutanoyloxy)dehydromelitensine (5), 8α-O-(3,4-dihydroxy-2-methylenebutanoyloxy)-15-oxo-5,7αH,6βH-eleman-1,3,11(13)-trien-6,12-olide (6), the germacranolides 8α-O-(4-acetoxy-2-hydroxymethylbuten-2-oyloxy)salonitenolide (7), cnicin (8), and 4‘-acetylcnicin (9), and the sesquiterpene methyl 8α-O-(3,4-dihydroxy-2-methylenebutanoyloxy)-6α,15-dihydroxyelema-1,3,11(13)-trien-12-oate (10), were isolated from the aerial parts of Centaurea spinosa. Nine known flavonoids were also isolated. The structures and the stereochemistry of the new compounds 1 and 2 were deduced by spectroscopic methods. The in vitro activity of 1−10 against three Gram-positive and three Gram-negative bacteria was evaluated using a microdilution method, and their in vitro cytotoxic activity was determined against a panel of human tumor cell lines.