[{"from": "human", "value": "Describe this molecule. [C][C][=C][C][=Branch1][C][=O][C@H1][Branch2][Ring2][S][C@][Branch2][Ring2][O][C@H1][Ring1][#Branch1][C][C@@H1][C@@][Branch2][Ring1][P][C@@H1][Ring1][=Branch1][C@H1][Branch2][Ring1][=Branch2][C@@H1][Branch2][Ring1][Ring2][C@@H1][Branch1][#C][C@@H1][Ring1][=Branch1][C@H1][Branch1][Branch2][C][=Branch1][C][=O][O][Ring1][O][O][C][O][O][O][C][C][O]"}, {"from": "gpt", "value": "The molecule is a quassinoid that is picras-3-ene substituted by hydroxy groups at positions 1, 11, 12, 15 and 21 and oxo groups at positions 2 and 16. Isolated from the ethanol extract of the stem of Brucea mollis, it exhibits cytotoxic activity. It has a role as a plant metabolite and an antineoplastic agent. It is a delta-lactone, an enone, a pentol, an organic heterotetracyclic compound, a quassinoid and a secondary alpha-hydroxy ketone. It derives from a hydride of a picrasane."}]