CCN(CC)Cc1cc(Nc2c3ccccc3nc3c4ccccc4n(C)c23)cc(CN(CC)CC)c1O.Cl
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?