O=C(N[C@H]1CCCc2ccccc21)O[C@@H]1C(=O)c2cc(Br)ccc2O[C@H]1c1ccc2c(c1)OCO2
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?