[{"from": "human", "value": "Provide a description of this molecule. [C][=N][C][=C][Branch1][=N][N][Ring1][Branch1][C][C][C][Branch1][Ring1][C][O][C][O][N][=C][Branch1][=Branch1][N][C][Ring1][=C][=O][N]"}, {"from": "gpt", "value": "The molecule is a member of the class of 2-aminopurines that is guanine in which the hydrogen at position 9 is substituted by a 4-hydroxy-3-(hydroxymethyl)but-1-yl group. An antiviral drug, it is administered topically for treatment of herpes labialis. A prodrug, famciclovir, is used for oral administration. It has a role as an antiviral drug. It is a member of 2-aminopurines and a member of propane-1,3-diols. It is functionally related to a guanine."}]