C/C(=N/NC(=O)C(N)=O)C(CC(C(=O)Nc1ccccc1C)/C(C)=N\NC(=O)C(N)=O)C(=O)Nc1ccccc1C
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?