CC1(C)C(=O)Nc2ccccc2N1C(=O)CSc1nnc2c(Cl)cc(Cl)cn12
An acid's negative base-10 logarithmic dissociation constant (pka) follows directly from its underlying thermodynamics; pKa is directly proportional to its standard Gibbs free energy change. What is the pka value of this molecule?