COc1c(C)cc(C(=O)C2CCCN(C(=O)c3cc(C4CC4)[nH]n3)C2)cc1C
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?