COc1ccccc1N1C(=O)NC(=O)/C(=C\NCc2ccc3c(c2)OCO3)C1=O
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?