COS(=O)(=O)[O-].C[n+]1c2ccccc2c(C(=O)Nc2ccc(S(=O)(=O)Nc3ccnn3-c3ccccc3)cc2)c2ccccc21
An acid's negative base-10 logarithmic dissociation constant (pKa) follows directly from its underlying thermodynamics; the negative pKa is directly proportional to its standard Gibbs free energy change. What is the negative pKa value of this molecule?