Study on the Chemical Components and Anti-Neuroinflammatory Activity of the Roots of Clausena excavate Burm. f.

The ethanol extract of the roots of Clausena excavata gave two previously undescribed coumarins, clauexcatin A (1) and clauexcatin B (2), as well as a pair of new isomers, trans/cis-clauexcatin C (3a, 3b), along with thirty known compounds. Among these, compound 33 was isolated from this genus for the first time. The structures of these compounds were elucidated based on their physicochemical properties and spectroscopic data. The anti-neuroinflammatory activities were assessed using LPS-activated BV-2 microglial cells. Compounds 6, 8, 17, 24, 29, and 30 exhibited significant inhibition of nitric oxide release in a dose-dependent manner, with their inhibitory effects being 1.2 to 10.9 times greater than that of the positive control (minocycline).