CCn1c(SCC(=O)N/N=C/c2c[nH]c3ccccc23)nnc1-c1ccc(Cl)cc1
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?