O=C(Cc1cccc(NC(=O)C2CCCN(C(=O)CCc3ccccc3)C2)c1)Nc1ccc(C(=O)N2CCOCC2)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?