Structural elucidation of spiro cyclohexandienonyl naphthalenes with potential anti-neuroinflammatory activities from Caragana acanthophylla Kom.

Abstract Four undescribed spiro cyclohexandienonyl naphthalenes (acanthophyllas A–D) and a revised compound were isolated from the roots of Caragana acanthophylla Kom. (Fabaceae). They were identified using extensive spectroscopic data and via chemical methods. Three of them were resolved into their enantiomers, and their absolute configurations were confirmed by comparing the experimental and calculated electronic circular dichroism spectra. Moreover, the anti-inflammatory activities of the compounds were investigated by evaluating their inhibitory effects on nitric oxide production in lipopolysaccharide-stimulated BV-2 cells. Some compounds showed significant inhibitory activities with IC50 values of 8.8–13.4 μM (minocycline, IC50 7.8 μM), indicating that they might serve as potential therapeutic agents for neurodegenerative diseases.