O=C(O)/C(=C\c1ccc(Cl)c([N+](=O)[O-])c1)c1ccc(S(=O)(=O)N2CCCCC2)s1
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?