CC(=O)O[C@@H]1C[C@](C)(OC(C)=O)C[C@H]2[C@]3(C)[C@@H](OC(C)=O)[C@@]4(O)C[C@H](C)[C@H](OC(=O)c5ccccc5)[C@@H]4[C@@H](OC(C)=O)[C@]3(C)C[C@@]21OC(C)=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?