Two new 2,3-seco-hopane triterpene derivatives from Megacodon stylophorus and their antiproliferative and antimicrobial activities.

Chemical investigation of the ethanol extract of the whole plant of Megacodon stylophorus led to the isolation and identification of two new seco-hopane triterpenoids, 2,3-seco-22(29)-hopene-2-carboxyl-3-aldehyde (1) and 2,3-seco-4(23),22(29)-hopene-2-carboxyl-3-aldehyde (2), along with 10 known compounds, 3-12. All the isolates were reported from this plant for the first time. The structures of compounds 1 and 2 were determined by detailed analysis of their spectral data including 1D and 2D NMR. In addition, compound 1 was further analyzed by X-ray crystallography. Compounds 1-3 were evaluated for their in vitro anti-proliferative activities on HeLa, MCF-7, and Hep-G2 tumor cell lines. Compound 2 was active against the three cell lines with IC50 values of 3.6, 7.5, and 13.6 µM, respectively, while compound 1 exhibited cytotoxicity on MCF-7 (IC50 14.0 µM) and HeLa (IC50 18.2 µM) cell lines. Antimicrobial activities of compounds 1-2 (minimum inhibitory concentration values in the range of 3.12-12.50 mg/mL) were also observed.

Norlathyrane diterpenes from the root of Euphorbia kansuensis.

Phytochemical investigation of the EtOH extract obtained from the root of the Euphorbia kansuensis Proch. grown in China resulted in the isolation of two novel norlathyrane diterpenes, named ekanpenoids A and B (1 and 2, resp.). Their structures were established by extensive 1D- and 2D-NMR spectroscopy, as well as other spectra. The isolated diterpenes exhibited potent cytotoxic activities against the HeLa and Hep-G2 cell lines with the IC50 values ranging from 3.6 to 9.7 µg/ml.

A new aromatic glycoside and its anti-proliferative activities from the leaves of Bergenia purpurascens.

Chemical investigation of the ethanolic extracts of the dried leaves of Bergenia purpurascens led to the isolation and identification of a new aromatic glycoside, 1-O-ß-D-glucopyranosyl-2-methoxy-3-hydroxyl-phenylethene (1), along with other 19 known compounds (2-20). The structure of compound 1 was determined by a detailed analysis using various analytical techniques, including 1D and 2D NMR. In vitro anti-proliferative activities of compound 1 on five human cancer cell lines were evaluated. The results showed that compound 1 possessed the most potent effects with the IC50 values of 14.36 ± 1.04 µM against T24 cells. The further bioactivity analysis showed that compound 1 induced apoptosis of T24 cells, and altered anti- and pro-apoptotic proteins, leading to mitochondrial dysfunction and activation of caspase-3 for causing cell apoptosis. The present investigation illustrated compound 1 might be used as a potential antitumour chemotherapy candidate.

Chemical Constituents of the Aerial Parts of Euphorbia nematocypha.

Chemical constituents of the dried aerial parts of Euphorbia nematocypha were investigated. A new oleanane triterpenoid, trans, trans-2',4'- hexadienedioicacid-1'-ß-amyrin ester (1), together with, ß-amyrin (2), ß-amyrin acetate (3), betulinic acid (4), ellagic acid (5), oleanolic acid (6), ß-sitosterol (7), kaempferol (8), quercetin (9), lupeol (10) and pseudo-taraxasterol (11) were isolated from the methylene chloride extract. Their structures were elucidated on the basis of extensive spectroscopic (1D- & 2D-NMR) and ESI-MS analysis and comparison with data reported in the literature. The new isolated triterpenoid showed moderate cytotoxic activities against HeLa and MCF-7cell lines.

Two new sesquiterpenes from Artemisia sieversiana.

Two new sesquiterpenes, together with 32 known compounds(3-34), were isolated from Artemisia sieversiana Ehrhart ex willd. and the compounds 3-21 were isolated from this plant for the first time. The new compounds were elucidated as 2α,9α-dihydroxymuurol-3(4)-en-12-oic acid (1) and 13α-methyl-(5αH,6αH,7αH,8αH)-austricin 8-O-ß-D-glucopyranoside (2), respectively. The structural identification of these compounds was mainly achieved by spectroscopic methods including 1D and 2D NMR techniques, and the structure of compound 1 was confirmed by a single crystal X-ray diffraction experiment. Compounds 1-2 were evaluated for cytotoxic activity in vitro against MCF-7, NCI-H460 and Hep-G2 cell lines, respectively.

Triterpenoids of Chrysosplenium carnosum.

A phytochemical study of the ethanolic extract of Chrysosplenium carnosum Hook. f. et Thoms. led to the isolation of two new oleanane-type triterpenoids, 6ß-hydroxy-3-oxoolean-12-en-27-oic acid (1) and 3ß, 21α-dihydroxyolean-12-en-27-oic acid (2), along with fourteen known compounds (3-16), all of which were isolated from this plant for the first time. The structures of these compounds were established on the basis of spectroscopic methods. Compounds 1-4 were evaluated for their in vitro anti-tumor activities on B16F10, SP2/0 and Hep-G2 cells lines. Compounds 1, 3 and 4 exhibited strong inhibitory activity against B16F10 and SP2/0 cells' growth, compared with moderate cytotoxic activity against Hep-G2 cells. However, compound 2 showed to be inactive against these tumor cells.