Cc1ccc(C(=O)N2CCc3cc(CNS(=O)(=O)c4ccc(Cl)s4)ccc32)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?