COc1ccc(NC(=O)CN(C)CC(=O)Nc2sc3c(c2C(N)=O)CCC3)cc1
An acid's negative base-10 logarithmic dissociation constant (pKa) follows directly from its underlying thermodynamics; the negative pKa is directly proportional to its standard Gibbs free energy change. What is the negative pKa value of this molecule?