COc1ccc(NC(=O)c2c(C)oc3ccc(O)c(CN4CCN(Cc5ccccc5)CC4)c23)cc1Cl
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?