CCOC(=O)C(=O)/C=C(\C)Nc1c(NC2OCC(OC(C)=O)C(OC(C)=O)C2OC(C)=O)nc(SC)[nH]c1=O
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?