CCOC(=O)c1sc2c(c1O)c(=O)n(-c1ccccc1)c(=S)n2-c1ccccc1
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?