COc1ccc(C(=O)NCCc2nnc3ccc(SCC(=O)Nc4cc(C)on4)nn23)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?