O=C1C(C2=NC(C(=O)O)C3C(=O)N(c4ccccc4)C(=O)C23)=C(O)c2ccccc21
An acid's negative base-10 logarithmic dissociation constant (pKa) follows directly from its underlying thermodynamics; the negative pKa is directly proportional to its standard Gibbs free energy change. What is the negative pKa value of this molecule?