[{"from": "human", "value": "Synthesize a molecule that matches the given characteristics. The molecule is a hydroxy monocarboxylic acid anion that is the conjugate base of mevalonic acid, arising from deprotonation of the carboxy group. It is functionally related to a valerate. It is a conjugate base of a mevalonic acid."}, {"from": "gpt", "value": "[C][C][Branch1][Ring2][C][C][O][Branch1][#Branch1][C][C][=Branch1][C][=O][O-1][O]"}]