O=C(NC1CCCC1)O[C@@H]1C(=O)c2cc(Br)ccc2O[C@H]1c1ccc2c(c1)OCO2
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?