COc1ccc(N2CC(=O)N(C(=O)COc3ccc(OCC(=O)N4C(=O)CN(c5ccc(OC)cc5)C4=S)cc3)C2=S)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?