COc1ccc(C(=O)/C=C/Nc2ccc(S(=O)(=O)Nc3cc(OC)nc(OC)n3)cc2)c(OC)c1
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?