Chemical constituents from Gnaphalium affine and their xanthine oxidase inhibitory activity.

Gnaphalium affine D. Don, a medicinal and edible plant, has been used to treat gout in traditional Chinese medicine and popularly consumed in China for a long time. A detailed phytochemical investigation on the aerial part of G.

Isoprenylated flavonoids from Morus nigra and their PPAR γ agonistic activities.

A novel dihydroflavonol unprecedentedly with a prenyl group at C-2, nigragenon A (1), four new sanggenon-type flavonones, nigragenons B-E (2-5), along with six known isoprenylated flavonoids (6-11) were isolated from the twigs of Morus nigra. Their structures were elucidated through extensive analysis of spectroscopic data. Interestingly, compound 1 was the first reported biogenetic precursor of sanggenon-type flavanones and the biogenetic pathway from 1 to sanggenol F was proposed.

Anti-proliferative and apoptotic effects of S1, a tetrandrine derivative, in human gastric cancer BGC-823 cells.

The aim of the study was to investigate the anti-proliferation and apoptosis-inducing effects of S1, a novel tetrandrine derivative, in human gastric cancer BGC-823 cells and explore the possible mechanism of action. The anti-proliferative activity was determined by MTT assay; the induction of cell cycle arrest and apoptosis were detected by flow cytometry. Quantitative real time RT-PCR and Western blotting were used to evaluate the mRNA and protein expression levels in mitochondrial pathway.

Synthesis and antitumor activity of tetrandrine derivatives.

Tetrandrine possesses antitumor activity, however, only a few studies on its structure modification were reported. To improve the antitumor activity of tetrandrine, 20 new tetrandrine derivatives were designed and synthesized by Sonogashira and Suzuki reactions. Their antitumor activities were evaluated against three tumor cell lines including A549, HepG2, and BGC-823 by methyl thiazolyl tetrazolium assay with taxol as a positive control.