NC(=O)Nc1cc(O)ccc1/N=N/c1ccc(S(=O)(=O)Nc2ccccn2)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?