COc1ccc(-c2ccc(NS(=O)(=O)c3cccc([N+](=O)[O-])c3)cc2)nn1
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?