[{"from": "human", "value": "Describe this molecule. [C][O][C][=Branch1][C][=O][C][C][=Branch1][C][=O][C][=Branch1][C][=O][O]"}, {"from": "gpt", "value": "The molecule is a dicarboxylic acid monoester comprising succinic acid having an oxo group at the 2-position and the methyl ester at the 4-position. It is functionally related to an oxaloacetic acid. It is a conjugate acid of an oxaloacetate 4-methyl ester."}]