[{"from": "human", "value": "Design a molecule that meets the criteria outlined in the description. The molecule is an oxacycle, an organonitrogen heterocyclic compound, an organic heterotricyclic compound and an alkaloid antibiotic."}, {"from": "gpt", "value": "[C][O][C][=C][C][=C][O][C][Ring1][Branch1][=N][C][=C][C][=C][C][=C][Ring1][=Branch1][Ring1][=N]"}]