COc1cccc(-c2cnc3c(NC(C)=O)cc(-c4ccc(C(=O)NC5CC5)cc4)cn23)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 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?