Cc1cccc(OCCCC(=O)Nc2ccc(S(=O)(=O)Nc3onc(C)c3C)cc2)c1
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?