COCc1cc(CN2CCCC(C(=O)Nc3cccc(-n4cnnn4)c3)C2)ccc1OC
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?