COc1cc2c(c(OC)c1OC)-c1c(cc3c(c1OC)OCO3)CC(C)C(C)(O)C2OC(=O)c1ccccc1
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?