CCOc1ccc(CCNC(=O)c2cc3n(n2)CCCN(Cc2ccc(C)cc2)C3=O)cc1OCC
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?