COc1cccc2c1[C@H](CO)N1[C@H](C#N)[C@@H]3C[C@H](C(=O)O)[C@@H]([C@@H]1C2)N3C
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?