CCOC(=O)c1ccc(N2CCN(c3cccc(OC)c3)CC2)c(NC(=O)Nc2ccc(OCC)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?