CCCCN(CC)CCNC(=O)c1cc2c(=O)n(CC)c3ccccc3c2s1
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?