N#Cc1c(NC(=O)CS(=O)(=O)c2ccc(Cl)cc2)sc2c1CCCCC2
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?