CCn1c(SCC(=O)Nc2nc3ccccc3s2)nc2c(c1=O)SC(C)C2
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?