COc1cc(-c2[nH]nc3c2C(c2ccoc2)C(C#N)=C(N)O3)cc(OC)c1OC
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?