Novel coumarin glycoside and phenethyl vanillate from Notopterygium forbesii and their binding affinities for opioid and dopamine receptors

New coumarin glycoside and phenethyl vanillate, along with 17 known compounds, were isolated from Notopterygium forbesii. Falcarindiol showed the highest binding affinities to the opioid and dopamine receptors. Bioactivity-guided fractionation of Notopterygium forbesii has resulted in the isolation of one new coumarin glycoside and one new phenethyl vanillate, together with seventeen known compounds. The structures of these compounds were characterized by spectroscopic methods. These compounds were evaluated for their binding affinities to the opioid and dopamine receptors, and falcarindiol showed weak binding affinities to opioid receptors and moderate affinity for D1 receptor ( K i = 192 ± 6 nM).