COc1cccc([C@@H]2Oc3ccc(OC)cc3/C(=N/OC[C@@H](C)[C@H](OCc3ccccc3)C(C)C)[C@@H]2O)c1
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?