COc1ccc(C2Oc3ccccc3C3=C2C(c2cccs2)n2ncnc2N3)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 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?