Abstract
A phytochemical investigation of the aerial parts of Achillea cretica L. led to the isolation of a new chlorine-containing sesquiterpene lactone (1) together with two new epimeric secoguaianolides of tanaphallin (2a,b) and the known vomifoliol (3). Their structures were elucidated by extensive application of one- and two-dimensional NMR spectroscopy and by comparison with authentic samples. Sesquiterpenes lactones are known to have great variety of pharmacological and biological activities such as antimicrobial, cytotoxic, antiviral, anti-inflammatory. Their great potential biological activities have more interest among chemists to the drug discovery research. In the present work, the isolates were tested for their cytotoxic activities against four different human cancer cell lines, HCT-116, IGROV-1, OVCAR-3 and MCF-7 using MTT assay. Compound 1 was found to be the most cytotoxic against the four tested cell lines with a relatively high selectivity against OVCAR-3 (IC50= 23.0 +/- 2.0 mu M). (C) 2015 Elsevier B.V. All rights reserved.