COc1ccc(/C=C/C(=O)Nc2c(C)nn(C)c2C)cc1COc1ccc(Cl)cc1Br
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?