COc1cc2cc(CNc3ccccc3)c(=O)n(CC(=O)Nc3cccc(Cl)c3C)c2cc1OC
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?