Guaianolides and phenolic constituents from Crepis dioscoridis L., growing wild in Greece

Fifteen compounds were isolated from the aerial parts of Crepis dioscoridis L., growing wild in Greece. These compounds comprise one new and nine known guaianolides, two flavonoids, two phenolic acids and one simple phenolic derivative. The structures of the isolated compounds were established by means of NMR [H-1-H-1 COSY, H-1-C-13 HSQC, HMBC, NOESY, ROESY] and MS spectral analyses. The main sesquiterpene lactones were by order of their abundance integrifolin 3 beta-D-glucopyranoside, crepiside C and 8-epi-grosheimin. These results are in agreement with previously studied Crepis sp.; this evidence could be of chemotaxonomic significance for the genus, since the predominance of costus type sesquiterpene lactones is a characteristic feature of the Crepis genus. It is noteworthy that some of them were also found in the genera Lapsana L. and Ixeris L., all belonging to the section Lactuceae of the sub-tribe Crepidinae. (C) 2013 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved.