Cc1nnc(SCC(=O)Nc2ccc(S(N)(=O)=O)cc2)n(N)c1=O
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?