COc1cc([C@@H]2c3cc4c(cc3[C@@H](NCCNCCO)[C@H]3COC(=O)[C@@H]32)OCO4)cc(OC)c1O.Cl
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?