COc1ccccc1N1CCN(S(=O)(=O)c2c(C)sc3ncn(CC(=O)Nc4ccc(C(F)(F)F)cc4)c(=O)c23)CC1
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?