O=C(Cn1ncc2c3ccccc3n(Cc3ccccc3)c2c1=O)NCc1ccco1
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 negative pKa value is directly proportional to the standard Gibbs free energy change for the reaction. What is the negative pKa value of this molecule?