[{"from": "human", "value": "Generate a molecule based on this description. The molecule is a 2-oxo monocarboxylic acid anion that is the conjugate base of 2-oxohexadecanoic acid arising from the deprotonation of the carboxy group; major species at pH 7.3. It is functionally related to a hexadecanoate. It is a conjugate base of a 2-oxohexadecanoic acid."}, {"from": "gpt", "value": "[C][C][C][C][C][C][C][C][C][C][C][C][C][C][C][=Branch1][C][=O][C][=Branch1][C][=O][O-1]"}]