Cc1ccc(Cl)cc1Nc1nn2c(=O)c3ccc(C(=O)NC(C)c4ccccc4)cc3nc2s1
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?