Cl.O=C(CCS(=O)(=O)c1ccccc1)N(CCCN1CCOCC1)c1nc2ccc(F)cc2s1
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?