O=C(O)CN1C(=O)C2C3CC(C2C1=O)C1C(c2ccccc2)c2sc(O)nc2SC31
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?