COc1cccc(C(C(=O)NC(C)(C)C)N(Cc2ccco2)C(=O)CCC(=O)Nc2cc(C)on2)c1OC
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?