[{"from": "human", "value": "Could you give me a brief overview of this molecule? [C][=C][C@H1][Branch1][O][C][C@@H1][Branch1][=Branch1][C@H1][Ring1][Branch1][C][O][O][N][C][=N][C][=C][Ring1][Branch1][N][=C][Branch1][=Branch1][N][C][Ring1][=Branch1][=O][N]"}, {"from": "gpt", "value": "The molecule is a guanosine nucleoside analogue used in the treatment of chronic hepatitis B virus (HBV) infection. Entecavir therapy can be associated with flares of the underlying hepatitis B during or after therapy, but has not been linked to cases of clinically apparent liver injury."}]