Two new lignan glucosides from caulis of Tinospora sinensis / 中草药

ABSTRACT

Objective To study the chemical constituents and anti-neuroinflammatory activity of the caulis of Tinospora sinensis as a "Yao" medicine. Methods The chemical constituents were isolated and purified by silica gel, Sephadex LH-20, ODS column chromatographies, and semi-preparative HPLC. The structures of these compounds were elucidated by extensive spectroscopic analyses and chemical methods. All compounds were evaluated for their anti-neuroinflammatory effect by inhibiting the nitric oxide (NO) production in lipopolysaccharide (LPS)-activated murine BV-2 microglial cells except for compounds 7 and 8. Results Thirteen compounds were isolated from the caulis of T. sinensis. They were identified as tinosposide C (1), tinosposide D (2), seco-isolariciresinol 9-O-β-glucopyranoside (3), (+)-pinoresinol 4-O-β-D-glucopyranoside (4), (+)-syringaresinol (5), tanegoside A (6), (E)-3-[(2,3-trans)-2-(4-hydroxy-3-methoxyphenyl)-3-hydroxymethyl-2,3-dihydrobenzo [b] [1,4]dioxin-6-yl]-N-(4-hydroxyphenethyl) acrylamide (7), thoreliamide B (8), trans-N-p-coumaroyltyramine (9), N-trans-feruloyltyramine (10), N-trans-caffeoyltyramine (11), grossamide K (12), and cis-grossamide K (13), seven of which exhibited significant anti-neuroinflammatory activity with IC50 values ranging from 1.46 to 51.25 μmol/L. Conclusion Compounds 1 and 2 are new compounds and their absolute configurations are confirmed by ECD experiments, compounds 3, 5, 7, 8, and 10-13 are isolated from the plants for the first time. The activity of compounds 9 and 10 is better than positive control minocycline.