[{"from": "human", "value": "Design a molecule that meets the criteria outlined in the description. The molecule is a methylguanine."}, {"from": "gpt", "value": "[C][N][C][=Branch1][C][=O][C][=C][Branch1][=Branch1][N][=C][N][Ring1][Branch1][N][=C][Ring1][#Branch2][N]"}]