CC1SC2(CCCCC2)N(NC(=O)CSc2nc3ccc(Cl)cc3c(=O)n2-c2ccccc2)C1=O
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?