Cc1ccc(N2CC(C(=O)N3CCC(C(=O)Nc4cccc(Br)c4)CC3)CC2=O)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?