COc1ccc(CN2CCN(S(=O)(=O)c3ccc(NC(C)=O)cc3)CC2)c(OC)c1OC.O=C(O)C(=O)O
An acid's negative base-10 logarithmic dissociation constant (pka) follows directly from its underlying thermodynamics; pKa is directly proportional to its standard Gibbs free energy change. What is the pka value of this molecule?