NC(=O)c1cc2c(-c3ccc(Nc4nc5ccccc5o4)cc3)cnc(N)c2s1
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?