[{"from": "human", "value": "Design a molecule that meets the criteria outlined in the description. The molecule is a nucleoside reverse transcriptase inhibitor analog of cytosine. Elvucitabine has activity against HIV and chronic hepatitis B."}, {"from": "gpt", "value": "[C][=C][C@H1][Branch1][#Branch1][O][C@H1][Ring1][Branch1][C][O][N][C][=C][Branch1][#Branch2][C][=Branch1][=Branch1][=N][C][Ring1][=Branch1][=O][N][F]"}]