CCOC(=O)C1=C(c2ccccc2)N=C(S)NC1c1cc([N+](=O)[O-])ccc1OC
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?