Cc1ccccc1NS(=O)(=O)c1cc(C(=O)Nc2cccc(N(C)S(C)(=O)=O)c2)ccc1C
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?