[{"from": "human", "value": "Describe this molecule. [C][C][Branch1][C][C][C][Branch1][=Branch1][C][=Branch1][C][=O][O-1][O]"}, {"from": "gpt", "value": "The molecule is a hydroxy monocarboxylic acid anion that is the conjugate base of 2-hydroxy-3-methylbutyric acid, formed by loss of a proton from the carboxy group. It has a role as a human metabolite. It is a conjugate base of a 2-hydroxy-3-methylbutyric acid."}]