CN(c1ccccc1)S(=O)(=O)c1ccc(NC(=O)C2CCCCC2C(=O)O)cc1
An acid's negative base-10 logarithmic dissociation constant (pKa) follows directly from its underlying thermodynamics; the negative pKa is directly proportional to its standard Gibbs free energy change. What is the negative pKa value of this molecule?