[{"from": "human", "value": "Provide a description of this molecule. [C][O][C][=C][Branch2][Ring2][Branch1][C][=C][Branch1][Branch1][C][=C][Ring1][=Branch1][C][S][=Branch1][C][=O][=Branch1][C][=O][/C][=C][/C][=C][Branch1][=N][C][=C][Branch1][#Branch1][C][=C][Ring1][=Branch1][O][C][O][C][O][C][N][C][C][=Branch1][C][=O][O-1]"}, {"from": "gpt", "value": "The molecule is a monocarboxylic acid anion that is the conjugate base of rigosertib, resulting from the deprotonation of the carboxy group. The major species at pH 7.3. It is a conjugate base of a rigosertib."}]