Iridoids and cycloartane saponins from mussaenda pilosissima valeton and their inhibitory NO production in BV2 cells.

One new iridoid glycoside (1), shanzhiside N-L-phenylalanyl ester along with seven known compounds, mussaenoside (2), shanzhiside methyl ester (3), barlerin (4), mussaendodise G (5), mussaendodise U (6), mussaendodise P (7), and mussaglaoside B (8) have been isolated from Mussaenda pilosissima Valeton. Their chemical structures were elucidated by spectroscopic methods, 1 D-, 2 D-NMR, and mass spectra. Compounds 1-7 showed significant inhibitory activity on LPS-stimulated NO production in BV2 cells with the IC₅₀ values ranging from 43.5 to 65.2 µM.