COc1ccc(C(=O)C2CCCN(C(=O)CCC3=NNC(=O)CC3)C2)c(C)c1
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?