O=C(COC(=O)/C=C/c1ccccc1[N+](=O)[O-])Nc1ccc(OC(F)F)cc1
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?