Isomadecassoside, a New Ursane-Type Triterpene Glycoside from Leaves, Reduces Nitrite Levels in LPS-Stimulated Macrophages.

A madecassoside-rich fraction obtained from the industrial purification of leaves afforded a new triterpene glycoside, named isomadecassoside (), characterized by an ursane-type skeleton and migration of the double bond at Δ in ring E. The structure of isomadecassoside was established by means of HR-ESIMS and detailed analysis of 1D and 2D NMR spectra, which allowed a complete NMR assignment. Studies on isolated J774A.1 macrophages stimulated by LPS revealed that isomadecassoside () inhibited nitrite production at non-cytotoxic concentrations, thus indicating an anti-inflammatory effect similar to that of madecassoside.