COc1ccc(-c2nc3ccccc3c(C(=O)Nc3ccc(S(=O)(=O)Nc4cc(C)on4)cc3)c2C)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?