Cc1c(CCOC(=O)c2ccc([N+](=O)[O-])cc2)sc[n+]1CC(=O)c1ccccc1.[Br-]
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?