CN1C[C@H](C(=O)N[C@@]2(C)O[C@@]3(O)[C@H]4CCCN4C(=O)[C@@H](Cc4ccccc4)N3C2=O)C=C2c3cccc4[nH]cc(c34)C[C@@H]21
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?