O=C(NCCCN1CCOCC1)c1cccc(S(=O)(=O)Nc2cc(Cl)ccc2Cl)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?