[{"from": "human", "value": "Based on the given information, design a molecule that meets the desired specifications. The molecule is a peripherally acting opioid antagonist which is used to treat constipation caused by chronic opioid use. Naldemedine has not been linked to serum enzyme elevations during therapy or to clinically apparent liver injury."}, {"from": "gpt", "value": "[C][C][Branch1][C][C][Branch2][Ring1][C][C][=N][C][=Branch1][Branch1][=N][O][Ring1][Branch1][C][=C][C][=C][C][=C][Ring1][=Branch1][N][C][=Branch1][C][=O][C][=C][Branch2][Ring2][#C][C@H1][C@@][C][C][N][Branch2][Ring1][P][C@@H1][Branch1][#Branch2][C@@][Ring1][=Branch1][Branch1][Ring2][C][Ring1][#Branch2][O][C][C][=C][Ring1][O][C][=Branch1][=Branch2][=C][Branch1][Branch1][C][=C][Ring1][=Branch1][O][O][Ring2][Ring1][C][C][C][C][C][Ring1][Ring1][O]"}]