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The roots of Cephalaria gigantea (LEDEB.) BOBROV (Dipsacaceae), an endemic plant of Caucasus growing in Georgia, 1) contain a large amount of triterpene saponins. 2-4) The roots are well-known in traditional medicine as sedative and anti-inflammatory remedies.1) Previous works reported the identification of six triterpene glycosides. 5,6) Antifungal and antiprotozoal activities of giganteosides D and E, major monodesmosides, have been evaluated.7) The present paper describes isolation and structure elucidation of three new triterpene saponins, named giganteosides L (1), M (2) and N (3) from the roots of Cephalaria gigantea. Their structures were established on the basis of 2D-NMR experiments (gs-COSY, gs-HMQC, gs-HMBC and gs-HSQC-TOCSY) and mass spectrometry (MALDI-TOF, ESI-HR-MS). Saponins containing glucuronic acid in the sugar chain are reported for the first time in Cephalaria species. In addition, eight known triterpene glycosides, giganteosides D (4), 5) E (5), 5) G (6), 6) H (7), 6) I (8), 8) K (9), 8) J (10) 9,10) and J 1 (11) 9,10) were isolated from this plant.Dried root of C. gigantea was extracted with boiling 80% MeOH and after filtration the solution was evaporated. The solid residue was dissolved in methanol and precipitated in acetone. A combination of low pressure liquid chromatography and repeated silica gel column chromatography allowed the purification of eleven glycosides (1-11) including three new ones. The structures of the new saponins (1-3) were established on the basis of acid hydrolysis, NMR (Tables 1, 2)

Terpenes U 0200 Antimalarial Activity of Sesquiterpene Lactones from Vernonia cinerea. -The new sesquiterpene lactones vernolide C (Ia) and D (Ib) and six known analogues are isolated from the dichloromethane fraction of an aqueous extract. -(CHEA, A.; HOUT, S.; LONG, C.; MARCOURT, L.; FAURE, R.; AZAS, N.; ELIAS*, R.; Chem.

Vernonia cinerea LESS (Asteraceae) is a perennial herbaceous plant mainly distribued in the tropical regions and commonly found in South-East Asia.1,2) Many therapeutic uses were reported for this plant, especially for the treatment of malaria fever and liver diseases. 3,4) In Cambodia, V. cinerea is called 'Kbal Ruy' by local residents, and is widely used as a traditional medicine for the treatment of fever and colics.1,5) An ethnobotanical survey in different regions of Cambodia indicated that this plant was found to be used as a febrifuge against malaria.6) It is worth noting that a far better antiplasmodial activity was found in the dichloromethane extract prepared from a decoction of the plant, compared with the dichloromethane extract directly prepared from the dried plant. The former extract was subjected to silica gel chromatography to yield two new sesquiterpene lactones, vernolides C 4 and D 8 (Fig. 1), along with six known compounds. This paper reports the identification and structural determination of the isolated compounds on the basis of spectroscopic analysis, including two-dimensional NMR and HR-ESI-MS data.The dichloromethane extract obtained from a decoction of the whole plant was subjected to repeated column chromatography affording eight sesquiterpene lactones as described in the Experimental section. By comparison of the physical and spectroscopic data of the compounds with literature reports on the same plant, 7) 1, 3 and 7 were identified as 8a-tigloyloxy-hirsutinolide-13-O-acetate, 8a-tigloyloxyhirsutinolide and 8a-(4-hydroxymethacryloyloxy)-hirsutinolide-13-O-acetate, respectively. Three further known lactones: 8a-epoxymethacryloyloxy-hirsutinolide-13-O-acetate 2, hirsutinolide-13-O-acetate 5 and piptocarphin D 6, described here for the first time in this plant, have been identified by comparison of their spectroscopic data with those published in the literature. [8][9][10][11][12][13][14] Vernolide C 4 was shown to be a chlorinated compound according to the typical cluster of ions in the mass spectrum at m/z 481 and 483; high resolution analysis of these ions as well as matching of isotopes allowed the composition to be determined as C 21 15) Detailed examination of the chemical shifts and long range CH correlations confirmed that the compound belonged to the hirsutinolide series with a proton onto C-10. That the hydrochlorination had taken place on the epoxide was shown by the presence of an AB quartet featuring H-3Ј of the ester side chain; all of the expected CH couplings be- Two new sesquiterpene lactones, vernolides C and D as well as six known ones were isolated from the dichloromethane fraction of an aqueous extract from Vernonia cinerea. Their structures were elucidated by spectroscopic methods. Among the known sesquiterpene lactones, three of them were described in this plant for the first time. In vitro antiplasmodial evaluation showed that the three major compounds 1, 7 and 8 were active against chloroquine resistant Plasmodium falciparum strain (W2) with IC 50 3.9, 3.7 and...

Three major alkaloids: cepharanthine (1), tetrahydropalmatine (2) and xylopinine (3) isolated from Stephania rotunda tuber were investigated for their cytotoxic activity in a panel of human cancer cells (HT29, LS174T, SW620 and HepG2) using MTT assay. In the present study, cepharanthine (1) exerted potent cytotoxicity against colon and hepatoma cancer cell lines with IC(50) values between 2.4 and 5.3 microM while tetrahydropalmatine (2) and xylopinine (3) displayed weak cytotoxicity. In addition, the mutagenic activity of cepharanthine (1) was investigated using a modified liquid incubation technique of the Salmonella/microsomal assay. This alkaloid (1) was found to be non-mutagenic for doses up to 8.2 microM.

The purpose of the present study was to screen 27 plant species used in the traditional medicine of Cambodia for in vitro antibacterial and antifungal activities. Thirty-three methanolic extracts were tested against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Mycobacterium smegmatis and Candida albicans. Screened by disk diffusion assay, the extracts showed antimicrobial activity especially on Gram-positive bacteria. None of the crude methanolic extracts showed activity against P. aeruginosa. Twenty-five selected extracts were evaluated using a micro-dilution test. Harrisonia perforata (roots) and Hymenodictyon excelsum (bark) exhibited a bactericidal effect against S. aureus at a concentration of 500 microg/ml. Azadirachta indica (bark), Harrisonia perforata (roots and stem) and Shorea obtusa (roots) exhibited a bactericidal effect against M. smegmatis at 250 microg/ml.