COc1ccc(S(=O)(=O)NCc2ccc3c(c2)CCN3C(=O)c2ccccc2)cc1OC
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?