O=C(Nc1ccc(Cl)cc1Cl)c1c/c(=N\O)c2ccc(O)cc2o1
The negative base-10 logarithmic of dissociation constant (pKa) for an acid is a direct consequence of the underlying thermodynamics of the dissociation reaction; the negative pKa value is directly proportional to the standard Gibbs free energy change for the reaction. What is the negative pKa value of this molecule?