O=C(Nc1cccc(Br)c1)c1c(O)c2c(n(Cc3ccccc3)c1=O)CCCC2
The negative base-10 logarithmic of dissociation constant (pKa) for an acid is a direct consequence of the underlying thermodynamics of the dissociation reaction; the negative pKa value is directly proportional to the standard Gibbs free energy change for the reaction. What is the negative pKa value of this molecule?