COc1ccc(/C=C/C2=NN(c3cccc(S(=O)(=O)O)c3)C3(C2)SCC(=O)N3c2nc3ccccc3s2)cc1
The negative base-10 logarithmic of dissociation constant (pKa) for an acid is a direct consequence of the underlying thermodynamics of the dissociation reaction; the negative pKa value is directly proportional to the standard Gibbs free energy change for the reaction. What is the negative pKa value of this molecule?