[{"from": "human", "value": "Generate a molecule based on the given description. The molecule is a hydroxy monocarboxylic acid anion that is the conjugate base of (S)-2-hydroxybutyric acid, obtained by decarboxylation of the carboxy group. It is a conjugate base of a (S)-2-hydroxybutyric acid."}, {"from": "gpt", "value": "[C][C][C@@H1][Branch1][=Branch1][C][=Branch1][C][=O][O-1][O]"}]