COc1ccc2cc(C(=O)COC(=O)COc3ccc4c(C)cc(=O)oc4c3)ccc2c1
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?