COc1ccc(C(CNC(=O)c2cccc(S(=O)(=O)N3CCCC3)c2)N2CCCC2)cc1
An acid's negative base-10 logarithmic dissociation constant (pka) follows directly from its underlying thermodynamics; pKa is directly proportional to its standard Gibbs free energy change. What is the pka value of this molecule?