Sesquiterpenes and diterpenes with cytotoxic activities from the aerial parts of Carpesium humile

Carpesium humile Winkl is an endemic Chinese species and no previous phytochemical studies have been reported for this species. Two new germacranolides and a new phytane diterpene were isolated from its aerial parts. Structures were elucidated using extensive spectroscopic analysis, X-ray crystallography, and CD exciton chirality methods. The germacranolides showed strong cytotoxic activities for six human cancer cell lines. The diterpene also displayed significant cytotoxic activities for selected cancer cell lines.162