COc1cc([C@@H]2c3cc4c(cc3[C@@H](NC(=O)NO)[C@H]3COC(=O)[C@@H]32)OCO4)cc(OC)c1O.Cl
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?