C[n+]1cccc(C(=O)NNC(=O)C23CC4CC(CC(C4)C2)C3)c1.[I-]
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?