COc1ccc(NC(=O)c2ccc(NC3CC(=O)N(c4ccc(C)cc4C)C3=O)cc2)cc1
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?