COc1cc(C2C(C(=O)Nc3ccccc3C)=C(C)Nc3nc(SCc4cc(C)ccc4C)nn32)ccc1O
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?