COc1ccc(-c2cc(=O)oc3c(C)c(OCC(=O)N[C@@H](Cc4ccc(O)cc4)C(=O)O)ccc23)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 pKa value is directly proportional to the standard Gibbs free energy change for the reaction. What is the pka value of this molecule?