COc1ccc(C/N=C/c2[nH]c3ccc(Br)c(Cl)c3c2O)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?