| Abstrakt: |
In a survey of plants from Ecuador with antiprotozoal activity, Cupania cinereawas found to show significant in vitro activity against the Plasmodium falciparumK1 strain and Trypanosoma brucei rhodesiense. Subsequently, activity-guided isolation of the n-hexane and dichloromethane extracts from the bark of C. cinereaafforded two diterpene glycosides (1and 2), named cupacinoside and 6′-de-O-acetylcupacinoside, and a lactonized triterpene bearing an oxepin moiety named cupacinoxepin (3), together with the known compounds scopoletin (4), caryophyllene oxide (5), two bisabolane sesquiterpenes (6and 7), lichexanthone (8), gustastatin (9), lupenone (10), betulone (11), 17β,21β-epoxyhopan-3-one (12), taraxerol (13), and taraxerone (14). For compound 3, X-ray crystallography was employed to elucidate the relative configuration. For cupacinosides (1) and (2) and cupacinoxepin (3), in vitro activities against the P. falciparumK1 strain (IC501, 1.3; 2, 1.8; and 3, 8.7 μM) and T. b. rhodesiense(IC501, 4.5; 2, 15.8; and 3, 71.6 μM) were found. Cytotoxicity toward L-6 cells is discussed for all the compounds isolated. |
