[{"from": "human", "value": "Synthesize a molecule that matches the given characteristics. The molecule is a monohydroxybenzoic acid that is 4-hydroxybenzoic acid substituted by a methyl group at position 3. It has a role as a human blood serum metabolite. It is a member of toluenes and a monohydroxybenzoic acid."}, {"from": "gpt", "value": "[C][C][=C][Branch1][=C][C][=C][C][=Branch1][Ring2][=C][Ring1][=Branch1][C][=Branch1][C][=O][O][O]"}]