O=C(NC(Cc1ccccc1)C(=O)O)/C(=C/c1cccc(Br)c1)NC(=O)c1ccco1
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 pKa value is directly proportional to the standard Gibbs free energy change for the reaction. What is the pka value of this molecule?