COc1ccc(C[C@@H]2C(=O)N[C@H](C)C(=O)N(C)[C@@H]3Cc4ccc(cc4)Oc4cc(ccc4O)C[C@H](C(=O)N[C@@H](C)C(=O)N[C@H](C)C(=O)N2C)N(C)C3=O)cc1
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?