Abstract: Eight compounds were isolated from the stems of Leycesteria formosa including one neolignan,two flavonoids,three caffeic acids and two triterpenoids.These compounds were identified as samwirin(1),cis-caffeic acid (2), trans-caffeic acid (3),luteolin(4),apigenin(5),3-ketooleanane (6),ursolic acid (7)and caffeic acid methyl ester (8),respectively.Compounds 1,2,4 and 5 were firstly isolated from L.formosa.In addition,the cytotoxic activities of 1 against A549 and HepG2 cell lines were investigated by MTT assay.The results showed that at the concentration of 40 μM,no cytotoxic activities were detected for 1 against A549 and HepG2 cell lines.

Key words: Leycesteria formosa, chemical constituents, lignans