CC(=O)c1ccc(S(=O)(=O)NC2CC(=O)N(c3ccc(Cl)cc3)C2)cc1
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?