CCOc1ccc(CCN2C(=S)N([C@@H](Cc3ccc(O)cc3)CN3CCC[C@@H]3CN3C(=S)NC[C@@H]3CC(C)C)C[C@@H]2Cc2ccc(O)cc2)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?