Cc1nn(C2CCS(=O)(=O)C2)c(Cl)c1/C=C/C(=O)OCC(=O)Nc1ccccc1[N+](=O)[O-]
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?