[{"from": "human", "value": "Synthesize a molecule that matches the given characteristics. The molecule is a dicarboxylic acid dianion resulting from the deprotonation of the two carboxy groups of 2,3-dimethylsuccinic acid ; major species at pH 7.3. It is a conjugate base of a 2,3-dimethylsuccinic acid."}, {"from": "gpt", "value": "[C][C][Branch1][#Branch2][C][Branch1][C][C][C][=Branch1][C][=O][O-1][C][=Branch1][C][=O][O-1]"}]