COc1ccc(NC(=O)CN2C(=O)CCc3cc(S(=O)(=O)N4CCOCC4)ccc32)cc1Cl
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?