CCOc1cccc(N2C(=O)CC(N3CCN(c4ccc(S(=O)(=O)CC)cc4)CC3)C2=O)c1
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?