[{"from": "human", "value": "What can you tell me about this molecule? [C][O][C][=Branch1][C][=O][C][C][=Branch1][C][=O][C][=Branch1][C][=O][O-1]"}, {"from": "gpt", "value": "The molecule is conjugate base of oxaloacetic acid 4-methyl ester; major species at pH 7.3. It is a conjugate base of an oxaloacetic acid 4-methyl ester."}]