COc1cc2nc(CN3CCN(S(=O)(=O)c4ccccc4[N+](=O)[O-])CC3)nc(O)c2cc1OC
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?