CN(C)[C@@H]1C(O)=C(C(N)=O)C(=O)[C@]2(O)C(O)=C3C(=O)c4c(O)cccc4[C@](C)(O)[C@H]3C[C@@H]12.CS(=O)(=O)O
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?