CC(C)[C@@H](C(=O)N[C@@H](C(=O)O)c1ccccc1)N1C(=O)N2CCc3c([nH]c4ccccc34)[C@@]2(C)C1=O
The negative base-10 logarithmic of dissociation constant (pka) for an acid is a direct consequence of the underlying thermodynamics of the dissociation reaction; the pKa value is directly proportional to the standard Gibbs free energy change for the reaction. What is the pka value of this molecule?