COC(=O)CNC(=O)[C@@]1(C)C=C[C@@H](Cc2ccccc2)N1C(C)=O
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?