CO[C@@]12C[C@@H](CNC(=O)c3cc(Br)c[nH]3)O[C@@H]1NC(=O)N2
An acid's negative base-10 logarithmic dissociation constant (pka) follows directly from its underlying thermodynamics; pKa is directly proportional to its standard Gibbs free energy change. What is the pka value of this molecule?