CC1CCN(Cc2c(O)ccc3c(O)c(-c4nc5ccccc5s4)c(=N)oc23)CC1
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?