O=C(O)CN1C(=O)/C(=C\c2cccc(OCc3ccc(Cl)cc3Cl)c2)SC1=S
The negative base-10 logarithmic of dissociation constant (pKa) for an acid is a direct consequence of the underlying thermodynamics of the dissociation reaction; the negative pKa value is directly proportional to the standard Gibbs free energy change for the reaction. What is the negative pKa value of this molecule?