CCC1CCc2c(sc(NC(=O)C3c4ccccc4Oc4ccccc43)c2C#N)C1
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?