O=C(NNc1cn[nH]c(=O)c1Cl)/C(=C/c1ccc2c(c1)OCO2)NC(=O)c1ccccc1
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?