[{"from": "human", "value": "Describe this molecule. [C][/C][=C][Branch1][C][\\C][/C][=Branch1][C][=O][O][C@@H1][C][C@@][Branch2][Ring1][P][C@H1][Branch1][Ring2][O][Ring1][Ring1][C][C@@H1][Branch2][Ring1][Branch1][/C][=Branch1][P][=C][/C@@H1][C@@H1][Ring1][O][C][=Branch1][C][=C][C][=Branch1][C][=O][O][Ring1][#Branch1][/C][O][C]"}, {"from": "gpt", "value": "The molecule is a sesquiterpene lactone of the heliangolide group isolated from Eupatorium kiirunense and Calea rotundifolia and exhibits cytotoxicity against human oral epidermoid (KB), cervical epitheloid (Hela) and liver (hepa59T/VGH) carcinoma cells. It has a role as an antineoplastic agent and a metabolite. It is a sesquiterpene lactone, an epoxide and an enoate ester. It is functionally related to a tiglic acid."}]