Anti-inflammatory flavone and chalcone derivatives from the roots of Pongamia pinnata (L.) Pierre

A phytochemical study on the roots of Pongamia pinnata (L.) Pierre yielded 52 flavonoids, including four previously undescribed flavone and four previously undescribed chalcone derivatives. The structures of the isolated compounds were determined on the basis of the 1D, 2D NMR, and mass spectroscopic data. The absolute configurations of the compounds were assigned via the specific rotation, Mosher's method, as well as the electronic circular dichroism (ECD) spectra. All the isolates were evaluated for their inhibitory effects on NO production in LPS-stimulated BV-2 microglial cells. Ten compounds showed significant inhibitory effects against NO production, comparable to the positive control, dexamethasone.