Six new alkaloid glycosides, Clausenasides A–F (1–6), along with two new quinoline alkaloids, Clausenasides G–H (7–8), and ten known compounds (9–18) were obtained from the stems of C. lansium. The structures of the new compounds were elucidated on the basis of their spectroscopic analysis, and the absolute configurations of 1, 2, 3 and 7 were confirmed by Mosher's method, CD and ECD spectra, respectively. Compounds 4, 6, 9, 17, and 18 showed moderate inhibitory effects on LPS-induced NO production in murine microglial BV2 cells (IC50 values < 10 μM).
