O=C(NC1CC1)c1cccc(NC(=O)C2CCN(S(=O)(=O)c3cccc(C(F)(F)F)c3)CC2)c1
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?