COc1ccc(NC(=O)CCS(=O)(=O)c2nc(-c3ccc4c(c3)OCO4)cc(C(F)(F)F)n2)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?