C=CCn1c(SCC(=O)c2ccc(CNC(C)=O)o2)nc2scc(C3CC3)c2c1=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?