Ixeris

Abstract: Introduction – Ixeris sonchifolia (Bunge) Hance, a folk medicine, has been widely used in China for its anti-inflammatory and haemostatic effects. However, the miscellaneous component composition of this herbal medicine is not well known. Objective – To develop a fast and comprehensive analytical method for the characterisation of various components from I. Sonchifolia, as a tool for the quality control of the herb and its related preparations. Methodology – Ixeris sonchifolia samples were extracted with 60% aqueous methanol, purified by solid-phase extraction and then analysed by the combinatorial use of HPLC-TOFMS and HPLC-ITMS. Results – A total of six sesquiterpene lactones, six phenolic acids and seven flavonoids were identified or tentatively characterised. Five of them were reported for the first time in I. sonchifolia and, in particular, two amino acid-sesquiterpene lactone conjugates, 11,13-dihydro-13-prolyl-ixerin Z and 11,13-dihydro-13-prolyl-ixerin Z1, that were first found in this plant source. Conclusion – A global profile of I. sonchifolia constituents was described, which could be useful for the quality control of this herb and its related preparations. The employed combination of HPLC-TOFMS and HPLC-ITMS could also be a promising tool for the analysis of other herbal medicines containing sesquiterpene lactones, phenolic acids or flavonoids. Copyright © 2010 John Wiley & Sons, Ltd.

Abstract: Bioassay-guided fractionation of an active n-BuOH extract of the whole plant of Ixeris sonchifolia, using a cytotoxicity assay, resulted in the isolation of three new triterpenoid saponins, ixeris saponins A (1), B (2), and C (3). On the basis of chemical evidence and extensive spectral studies, their structures were established as echinocystic acid 3-O-beta-D-glucopyranosyl(1-->3)-beta-D-glucopyranosyl(1-->3)-alpha- L-arabinopyranoside (1), 3-O-[bis[beta-D-glucopyranosyl(1-->2 and 1-->3)-alpha-L-arabinopyranosyl]]echinocystic acid 28-O-beta-D-glucopyranosyl ester (2), and 3- O-[beta-D-glucopyranosyl(1-->3)-beta- D-glucopyranosyl(1-->3)-alpha-L-arabinopyranosyl]-16alpha, 23-dihydroxyolean-12-ene 28-O-beta-D-glucopyranosyl ester (3). Compounds 2 and 3 showed significant cytotoxicity against cancer cell lines A375, L929, and HeLa with IC50 values ranging from 8.83 microM to 15.83 microM, while compound 1 was inactive against these three cell lines.

Abstract: Three new guaianolides, 10α-hydroxy-3-oxoguaia-4(15),11(13)-dieno-12,6α-lactone (1), 10α-hydroxy-3-oxo-4βH-guaia-11(13)-eno-12,6α-lactone (2), and 10α-hydroxy-3-oxoguaia-4,11(13)-dieno-12,6α-lactone (3), named chinensiolides A, B, and C were isolated from the whole plant of Siyekucai (Ixeris chinensis). The structures were determined by HREIMS, UV, IR, and one- and two-dimensional NMR techniques (1H and 13C NMR, COSY, HMQC, HMBC, and NOE difference and NOESY experiments). Compounds 1 and 2 were indicated to be a mixture of flexible conformers by analyses of their 1D NOE and NOESY spectra as well as the temperature dependence of their 1H and 13C NMR spectra. Chinensiolide B (2) was transformed to chinensiolide C (3) in a three-step conversion.