[{"from": "human", "value": "Create a molecule that satisfies the conditions outlined in the description. The molecule is an organophosphonate oxoanion that is the conjugate base of hydroxymethylphosphonic acid, obtained by deprotonation of one of the phosphonate OH groups. It is a conjugate base of a hydroxymethylphosphonic acid."}, {"from": "gpt", "value": "[C][Branch1][C][O][P][=Branch1][C][=O][Branch1][C][O][O-1]"}]