CC1(C)C=C(/C=N/Nc2ccc([N+](=O)[O-])cc2)C(C#N)=C(O)C1(C#N)C#N
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?