O=C(O)CCN1C(=O)C2C3C=CC(C2C1=O)C1C(=O)N(CCC(=O)O)C(=O)C31
The negative base-10 logarithmic of dissociation constant (pka) for an acid is a direct consequence of the underlying thermodynamics of the dissociation reaction; the pKa value is directly proportional to the standard Gibbs free energy change for the reaction. What is the pka value of this molecule?