COc1cc(S(=O)(=O)Nc2nc(-c3ccc(/N=C/c4ccccc4O)cc3)cs2)ccc1Cl
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?