COc1ccc(-c2cc(C(=O)OC(C)C(=O)Nc3c(C)n(C)n(-c4ccccc4)c3=O)c3ccccc3n2)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?