CC1CCN(S(=O)(=O)c2ccc(NC(=O)C3CCN(C(=O)c4ccco4)CC3)cc2)CC1
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?