COc1ccc(CC(NC(C)=O)C(=O)N2CCN(C(=O)N(C(C)C)C(C)C)CC2)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?