A new iridoid glycoside and NO production inhibitory activity of compounds isolated from Russelia equisetiformis.

From the 1-BuOH-soluble fraction of a MeOH extract of the leaves of Russelia equisetiformis, one new iridoid glucoside was isolated along with 24 known compounds, comprising iridoids and iridoid glucosides, phenyl propane glucosides, phenyl ethanoids, lignan glucosides, and flavonoid glucosides. The structure of the new compound was elucidated to be 10-O-cinnamoyl sinuatol. Of the 25 compounds isolated, rehmaglutin B exhibited moderate inhibitory activity toward NO production, which was not associated with cytotoxicity.