COC(=O)[C@H]1[C@@H](OS(=O)(=O)O)CC[C@H]2CN3CCc4c([nH]c5ccccc45)[C@@H]3C[C@H]21
An acid's negative base-10 logarithmic dissociation constant (pka) follows directly from its underlying thermodynamics; pKa is directly proportional to its standard Gibbs free energy change. What is the pka value of this molecule?