COCCN1CCc2nc(SCC(=O)Nc3ccc(C)c(Cl)c3)[nH]c(=O)c2C1
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?