Constituents of Tinospora sinensis and their nitric oxide inhibitory activities

One new phenylpropanoid glycoside, tinosinen A (1) and 13 known compounds, tinosinen (2), citrusin B (3), picraquassioside C (4), erythro-guaiacylglycerol-β-O-4'-coniferyl alcohol (5), erythro-guaiacylglycerol-8-O-4'-(sinapyl alcohol) ether (6), erythro-syringylglycerol-8-O-4'-(sinapyl alcohol) ether (7), seco-isolariciresinol 9-O-D-β-glucopyranoside (8), tinosposide A (9), pinoresinol-4'-O-β-D-glucopyranoside (10), syringaresinol-4'-O-β-D-glucopyranoside (11), pinoresinol (12), syringaresinol (13), and lirioresino-β-dimethyl ether (14) were isolated from the stems of Tinospora sinensis (Lour.) Merr. Their structures were established by detailed spectroscopic studies and comparisons with those reported in the literature. Compound 13 showed significant inhibitory NO production (IC₅₀ value of 38.53 ± 1.90 μM) in RAW264.7 macrophages, LPS-stimulated. Compounds 3-7, 11, 12, and 14 inhibited NO production with IC₅₀ values ranging from 38.53 to 99.07 μM.