COc1cc(O)c(C(CC(=O)N2CCCC(C)C2)c2ccc(N(C)C)cc2)c(OC)c1
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?