C=CCNC(=O)C1CC(=O)N(c2ccc(OCC(=O)Nc3ccc(OC)cc3)cc2)C1
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?