Characterisation of four new triterpenoid saponins with nitric oxide inhibitory activity from aerial parts of Gouania leptostachya.

Four new triterpenoid saponins (gouaniasides VII-IX [1-3] and joazeiroside C [4]) and one known triterpenoid (5) were isolated from the aerial parts of Gouania leptostachya DC. (Rhamnaceae). Their structures were elucidated via one-dimensional and two-dimensional nuclear magnetic resonance spectroscopy, high-resolution electrospray ionisation-mass spectrometry, and analyses of hydrolytic cleavage results. The anti-inflammatory potential of compounds 1-3 was evaluated according to their ability to inhibit the production of nitric oxide (NO) by RAW 264.7 macrophages. All compounds at noncytotoxic concentrations significantly inhibited NO production by macrophages in a concentration-dependent manner.

Cytotoxic sesquiterpene glucosides from Fissistigma pallens.

Six undescribed sesquiterpene glucosides, fissispallins A-F, and one known sesquiterpene glucoside, fissispallin, were discovered in the leaves of Fissistigma pallens (Finet & Gagnep.) Merr. The structures were determined using spectroscopic methods, including 1D, 2D NMR, and MS. All compounds were evaluated for cytotoxic activity against three human cancer cell lines, HT-29, A-2058, and A-549. Fissispallin A showed potent activity with the IC50 values less than 1.5 µM against all tested human cancer cell lines. Fissispallin also showed potent activity with IC50 value of 0.4 ± 0.3 on the A-2058 cancer cell lines. Fissispallins B-D showed significant cytotoxic activity against all the tested cancer cell lines with IC50 values ranging from 3.8 to 7.2 µM.

Four New Compounds Isolated from the Aerial Part of Belamcanda chinensis (L.) and Their Effect on Vascular Smooth Muscle Cell (VSMC) Proliferation.

Bio-guided fractionation of the 70% ethanol extract of Belamcanda chinensis (L.) DC. revealed four new compounds, including 6″-O-acetylembinin (5), 3″-O-acetylembinin (6), irigenin 3'-O-ß-glucopyranoside (8), and 2'-acetyl-1,3-O-diferuloylsucrose (9), along with five known compounds (1-4, 7). Their chemical structures were determined using extensive NMR data, mass spectroscopy, and comparison with published literature. Among the isolates, compounds 1 and 4-7 achieved good regulation of the growth and proliferation of vascular smooth muscle cells.