NC(=O)c1ccc2c(=O)n3c(-c4cc(Cl)c(N)c(Cl)c4)csc3nc2c1
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 pKa value is directly proportional to the standard Gibbs free energy change for the reaction. What is the pka value of this molecule?