COc1ccc(NC(=O)CC(=O)N2N=C(c3ccccc3)C(/N=N/c3ccc(S(=O)(=O)CCOS(=O)(=O)O)cc3)C2=O)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?