[{"from": "human", "value": "Based on the given information, design a molecule that meets the desired specifications. The molecule is a 2-oxo monocarboxylic acid anion that is the conjugate base of 3-methyl-2-oxobutanoic acid, arising from deprotonation of the carboxy group. It has a role as a human metabolite and a Saccharomyces cerevisiae metabolite. It is a 2-oxo monocarboxylic acid anion, an oxo fatty acid anion, a branched-chain fatty acid anion and a branched-chain keto acid anion. It is functionally related to a butyrate. It is a conjugate base of a 3-methyl-2-oxobutanoic acid."}, {"from": "gpt", "value": "[C][C][Branch1][C][C][C][=Branch1][C][=O][C][=Branch1][C][=O][O-1]"}]