N#Cc1c(-c2ccc([N+](=O)[O-])cc2)c(C#N)c(=O)n(NS(=O)(=O)c2ccccc2)c1O
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?