COc1cc(C(=O)N/C(=C\c2cn(S(=O)(=O)N(C)C)c3ccccc23)C(=O)NCCCO)cc(OC)c1OC
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?