O=C(NN/C=C1\C(=O)N(c2ccc(Cl)cn2)C(=O)c2ccccc21)c1ccncc1
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?