COc1ccc([N+](=O)[O-])cc1N=C(S)NC(NC(=O)C(c1ccccc1)c1ccccc1)C(Cl)(Cl)Cl
An acid's negative base-10 logarithmic dissociation constant (pka) follows directly from its underlying thermodynamics; pKa is directly proportional to its standard Gibbs free energy change. What is the pka value of this molecule?