CCOC(=O)c1c(NC(=O)COC(=O)CCOc2ccc(OCC)cc2)sc(C(=O)N(C)C)c1C
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?