CN1C(=O)c2ccccc2Sc2ccc(NC(=O)Cc3ccc(Cl)cc3)cc21
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?