[{"from": "human", "value": "Design a molecule that meets the criteria outlined in the description. The molecule is the simplest member of the class of bufadienolides that is bufanolide with unsaturation at positions 20 and 22."}, {"from": "gpt", "value": "[C][C@][C][C][C@H1][C@H1][Branch2][Ring1][Ring2][C@H1][Ring1][=Branch1][C][C][C@@H1][Ring1][=Branch2][C][=C][O][C][=Branch1][C][=O][C][=C][Ring1][#Branch1][C][C][C][C@@][Ring1][P][Branch1][#Branch1][C][C][C][C][Ring1][=Branch1][C]"}]