COc1ccc(C(=O)NNC(=O)c2ccccc2[N+](=O)[O-])cc1[N+](=O)[O-]
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?