COc1c(CC=C(C)C)c2c(c3oc(=O)c(-c4ccc(O)cc4)c(O)c13)C=CC(C)(C)O2
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?