[{"from": "human", "value": "Generate a molecule based on the given description. The molecule is a L-valyl ester. It has a role as an antiviral drug. It is functionally related to a guanine."}, {"from": "gpt", "value": "[C][C][Branch1][C][C][C@@H1][Branch2][Ring1][O][C][=Branch1][C][=O][O][C][C][O][C][N][C][=N][C][=C][Ring1][Branch1][N][=C][Branch1][=Branch1][N][C][Ring1][=Branch1][=O][N][N]"}]