Lignans with NO inhibitory activity from Tinospora sinensis

Area of Science:

• Natural Product Chemistry
• Pharmacology

Background:

• Tinospora sinensis is a plant used in traditional medicine.
• Phytochemical investigation of Tinospora species can yield novel bioactive compounds.

Purpose of the Study:

• To isolate and characterize new lignan glucosides and oxyneolignans from Tinospora sinensis.
• To evaluate the anti-inflammatory potential of isolated compounds by assessing their inhibitory effects on nitric oxide (NO) production.

Main Methods:

• Isolation of compounds using chromatographic techniques.
• Structure elucidation through comprehensive spectroscopic analysis (NMR, MS).
• Determination of absolute configuration using Electronic Circular Dichroism (ECD) calculations and Time-Dependent Density Functional Theory (TD-DFT).
• In vitro evaluation of nitric oxide inhibitory activity in lipopolysaccharide (LPS)-stimulated murine RAW264.7 macrophage cells.

Main Results:

• Five compounds were isolated, including two new lignan glucosides (tinsinlignans A and B) and two new oxyneolignans (tinsinlignans C and D).
• The structures were confirmed by spectroscopic data analysis, and the absolute configuration of tinsinlignan A was determined.
• Compounds 1 and 2 demonstrated moderate inhibitory activity against NO production with IC50 values of 18.5 ± 2.0 and 28.8 ± 1.2 μmol·L⁻¹, respectively.

Conclusions:

• Tinospora sinensis is a source of novel lignan glucosides and oxyneolignans.
• Tinsinlignans A and B possess moderate anti-inflammatory properties, indicated by their ability to inhibit nitric oxide production.