CC1=C(C(=O)Nc2ccc(Cl)cc2)C(C(C)C)n2nc(SCc3cccc(C)c3)nc2N1
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?