[{"from": "human", "value": "Generate a molecule based on this description. The molecule is a glycol that is 1,2-butanediol carrying an additional methyl substituent at position 2. It derives from a hydride of an isopentane."}, {"from": "gpt", "value": "[C][C][C][Branch1][C][C][Branch1][Ring1][C][O][O]"}]