[{"from": "human", "value": "Create a molecule with the structure as the one described. The molecule is a monocarboxylic acid anion that is obtained by removal of a proton from the carboxylic acid group of methacrylic acid. It is functionally related to an acrylate. It is a conjugate base of a methacrylic acid."}, {"from": "gpt", "value": "[C][C][=Branch1][C][=C][C][=Branch1][C][=O][O-1]"}]