[{"from": "human", "value": "Generate a molecule based on this description. The molecule is a branched-chain saturated fatty acid anion that is the conjugate base of 17-methyloctadecanoic acid, obtained by deprotonation of the carboxy group; major species at pH 7.3. It is a branched-chain saturated fatty acid anion, a long-chain fatty acid anion and a methyl-branched fatty acid anion. It is a conjugate base of a 17-methyloctadecanoic acid."}, {"from": "gpt", "value": "[C][C][Branch1][C][C][C][C][C][C][C][C][C][C][C][C][C][C][C][C][C][C][=Branch1][C][=O][O-1]"}]