New monoterpenoid indole alkaloids from Melodinus suaveolens

Abstract Three new monoterpenoid indole alkaloids ( 1 – 3 ), along with five known alkaloids ( 4 – 8 ), were isolated from the leaves of Melodinus suaveolens . Their structures were determined by extensive spectroscopic method and quantum chemical ECD calculation. All the new compounds were evaluated for their inhibitory effects on LPS-induced nitric oxide (NO) production in RAW 264.7 macrophages.