O=C1CC(NC(=O)C(F)(F)F)c2c(Br)sc(N3CCC(c4ccccc4)CC3)c21
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 negative pKa value is directly proportional to the standard Gibbs free energy change for the reaction. What is the negative pKa value of this molecule?